Referring to the type that growing on twigs of Abies.

This new genus is similar to Coccomyces De Not. on coniferous twigs and barks, but differs from Coccomyces by truncate acsi. Abiomyces is also similar to Therrya Sacc., but differs in having simple paraphyses, which do not form an epithecium, and aseptate ascospores.

Abiomyces laojunshanensis Lan Zhuo & C.L. Hou, described below.

Ascomata on twigs of Abies, scattered, round or slightly irregular, black (#000000), opening by radial or irregular splits to expose a yellow (#ffd400) to pale orange (#ffa500) hymenium. In median vertical section, ascomata intracortical. Lips absent. Covering stroma well developed. Basal Covering stroma poorly developed. Internal matrix of Covering stroma present, consisting of hyaline, thin-walled, angular cells with some irregular crystalloids and short hyphae. Subhymenium consisting of small, hyaline cells. Paraphyses filiform, simple. Asci clavate, thin-walled, J–, 8-spored. Ascospores aseptate, filiform, hyaline, without a gelatinous sheath.

Conidiomata and zone lines not seen.

Phylogenetically, the molecular sequences of species belonging to this new genus form a distinct lineage (Clade 3, Fig. 1) with high support (MLB = 100%, MPB = 97%, PP = 1.00). In the phylogenetic tree, the sequences of species of Abiomyces are clustered with sequences of species of Cudoniaceae, a group of fungi that live in the soil and leaf litter. Some species of Cudoniaceae are associated with conifer, so that the species of Abiomyces and Cudoniaceae may have evolved together in the same habitat.

Morphologically, the ascomatal shape of A. laojunshanensis is similar to those of Coccomyces and Therrya that develop on twigs of conifers. Until now, 16 species of Coccomyces have been reported growing on coniferous twigs and bark (https://www.ars.usda.gov/). However, except for Co. mertensianae, other species in Coccomyces lacks apically truncate asci. Species of Therrya differ from A. laojunshanensis by apically inflated paraphyses embedded in gelatinous sheaths forming an epithecium and multi-septate ascospores (Reid and Cain 1961; Sherwood 1980). Based on the separate phylogenetic positions and morphological characteristics, we propose Abiomyces as a separate genus.

Referring to the host genus Abies.

This new species is similar to Coccomyces mertensianae Sherwood, but Abiomyces laojunshanensis has longer, fili-fusiform ascospores.

CHINA, Yunnan Province, Lijiang, Laojunshan, 26.6310°N, 99.7227°E, alt. ca. 3930 m, on twigs of Abies georgei Orr (Pinaceae), 17 Aug 2023, C.L. Hou, L. Zhuo, and S.Y. Zhao, HOU 2070 (BJTC 2023200, holotype).

Ascomata on twigs, scattered, not associated with pale areas. In surface view, ascomata subround or slightly irregular, 500–1250 × 750–1500 µm, black (#000000), erumpent from the bark, opening by radial splits to expose a yellow (#ffd400) to pale orange (#ffa500) hymenium. Lips absent. In median vertical section, ascomata intracortical. Covering stroma 30–50 μm thick near center of ascomata, not extending to the basal Covering stroma, consisting of an outer layer of remains of the host cortex and an inner layer of carbonized, angular to globose cells. Basal Covering stroma poorly developed, consisting of carbonized, angular to globose cells. Internal matrix of Covering stroma 375–470 µm thick, consisting of hyaline, thin-walled, angular cells with some irregular crystalloids and short hyphae. Subhymenium 40–60 µm thick, consisting of small, hyaline cells. Paraphyses aseptate, filiform, not branched, not swollen at tips, 130–150 × ca. 1 µm, covered by a thin gelatinous sheath. Asci ripening sequentially, clavate, apex truncate, 80–90 × 8–10 µm, stalked, thin-walled, J–, 8-spored. Ascospores aseptate, filiform to fusiform, 50–65 × 3 μm, hyaline, without a gelatinous sheath.

Conidiomata and zone lines not seen.

CHINA, Yunnan Province, Lijiang, Laojunshan, 26.6314°N, 99.7235°E, alt. ca. 3880 m, on twigs of Abies georgei, 17 Aug. 2023, C.L. Hou, L. Zhuo, and S.Y. Zhao, HOU 2064 (BJTC 2023194); CHINA, Yunnan Province, Dali Bai Autonomous Prefecture, Mount Cangshan, 25.6644°N, 100.1024°E, alt. ca. 3830 m, on twigs of Abies delavayi Franch. (Pinaceae), 18 Aug. 2023, C.L. Hou, L. Zhuo, and S.Y. Zhao, HOU 2113 (BJTC 2023244).

Known only from Yunnan Province, China.

Morphologically, A. laojunshanensis resembles Coccomyces mertensianae growing on twigs of Tsuga mertensiana (Bong.) Carrière, however, Coccomyces mertensianae has septate paraphyses and shorter (19–25 × 2.5–3.0 µm), narrowly clavate ascospores. The multi-locus gene analysis indicates that the molecular sequences of A. laojunshanensis form an independent clade with high support (MLB = 100%, MPB = 100%, PP = 1.00). These sequences do not cluster with any species of Coccomyces, especially the type Co. tumidus (Fr.) De Not. Therefore, A. laojunshanensis is considered as a species new to science.

Figure 2. 

Abiomyces laojunshanensis (HOU 2070/BJTC 2023200, holotype) a ascomata on a twig of Abies georgei b, c mature ascomata. Scale bars: 3 mm (a); 500 μm (b, c).

Figure 3. 

Abiomyces laojunshanensis on Abies georgei (HOU 2070/BJTC 2023200, holotype) a part of an ascoma in vertical section, the internal matrix of Covering stroma filled with numerous crystals b paraphyses, mature asci with ascospores, and immature ascus. c Liberated ascospores. Scale bars: 50 μm (a); 10 μm (b, c).

CHINA, Yunnan Province, Lijiang, Laojunshan, 26.6323°N, 99.7252°E, alt. ca. 3880 m, on twigs of Abies georgei, 16 Jul. 2020, C.L. Hou, M.J. Guo, and Q.T. Wang, HOU 1608ZI (BJTC 2020049).

In the multigene phylogenetic analysis, the molecular sequence of this specimen is closely related to A. laojunshanensis with strong support (MLB = 100%, MPB = 97%, PP = 1.00). The ITS rDNA sequence similarity of these two species is 94%. Unfortunately, ascomata could not be found for this species. Mature ascomata are necessary to clarify specific morphological features of the species.

Crypto (Latin) = hidden, referring to the hidden ascomata of the type and morphological similarity with species of the genus Coccomyces.

Species of this new genus are morphologically similar to some species of Coccomyces that inhabit coniferous twigs and bark, but are phylogenetically distant from the type of Coccomyces, Co. tumidus, which inhabits leaves, as shown in the phylogenetic tree.

Cryptococcomyces occultus Lan Zhuo & C.L. Hou, described below.

Ascomata on twigs of Juniperus spp., scattered, round, elliptical or slightly irregular, black (#000000) or concolorous with the surface of the substrate, opening by radial or irregular splits to expose a pale yellow (#ffff9d) to pale orange (#ffa500) hymenium. Lips absent. Ascomata intracortical. Covering stroma well developed. Basal Covering stroma absent or present, consisting of carbonized, thick-walled, angular to globose cells. Internal matrix of Covering stroma absent or present, consisting of hyaline, thin-walled, angular cells and short hyphae; in some species, the matrix is filled with crystals. Subhymenium flat or slightly depressed, consisting of hyaline textura porrecta. Paraphyses filiform, branched or not branched, not swollen at tips. Asci ripening sequentially, clavate, thin-walled, J–, 8-spored. Ascospores aseptate, filiform, hyaline, covered or not covered by a gelatinous sheath.

Conidiomata and zone lines not seen.

Phylogenetically, molecular sequence data obtained from specimens cited below for species of Cryptococcomyces cluster together with a sequence in GenBank labelled “Colpoma juniperi (P. Karst.) Dennis Lantz 395” with high support (MLB = 99%, PP = 0.97; Clade 1, Fig. 1). According to molecular sequence data, this clade is distantly related to the type species of Colpoma, Colpoma quercinum (Pers.) Wallr. Species of Cryptococcomyces do not belong to the genus Colpoma according to molecular sequence data.

In addition, the round ascomata with radial or irregular openings of the species in the new genus resemble those of the genus Coccomyces rather than Colpoma (Sherwood 1980; Johnston 1991). However, the clade formed by molecular sequences of Cryptococcomyces is phylogenetically distinct from the type of Coccomyces, Co. tumidus. Therefore, these species are not congeneric with Coccomyces. Additionally, species in Cryptococcomyces all grow on twigs of Juniperus spp. Based on morphological characteristics, phylogenetic analysis, and the host relationship, Cry. juniperi is proposed to belong to the genus Cryptococcomyces.

Carbo- (Latin) = carbonized, -stoma (Latin) = opening, referring to strongly carbonized opening of ascomata.

This new species is similar to Cryptococcomyces niger, but differs by the presence of a basal Covering stroma and ascospores covered by a thick gelatinous sheath.

CHINA, Yunnan Province, Lijiang, Laojunshan, 26.6418°N, 99.7673°E, alt. ca. 3495 m, on twigs of Juniperus squamata D. Don (Cupressaceae), 16 Aug. 2023, C.L. Hou, L. Zhuo, and S.Y. Zhao, HOU 2025 (BJTC 2023155, holotype).

Ascomata on twigs, erumpent from bark, scattered, not associated with pale areas. In surface view, ascomata round or slightly irregular, 1000–2000 × 750–1000 µm, black (#000000), opening by irregular splits to expose a yellow (#ffe562) hymenium. Lips absent. In median vertical section, ascomata intracortical. Covering stroma 100–175 μm thick near the center of ascomata, consisting of an outer layer of remains of the host cortex, an inner layer of carbonized, angular to globose cells, and an innermost layer of hyaline textura prismatica. Basal Covering stroma 25–35 µm thick, consisting of 3–7 μm diam., thick-walled, angular to globose cells. Internal matrix of Covering stroma 40–65 µm thick, consisting of hyaline, thin-walled, angular cells, filled with irregular crystals. Subhymenium 25–20 µm thick, consisting of hyaline textura porrecta. Paraphyses aseptate, filiform, not branched, curled or coiled at their tips, 130–145 × 1–1.5 µm, covered by a thin gelatinous sheath. Asci ripening sequentially, clavate, apex acute, 80–120 × 6–8 µm, thin-walled, J–, 8-spored. Ascospores aseptate, filiform, tapering towards the apex, 30–40 × 1–1.5 μm, hyaline, covered by a ca. 2 µm thick gelatinous sheath.

Conidiomata and zone lines not seen.

Known only from Yunnan Province, China.

The multi-locus gene analysis indicates that the sequences of Cry. carbostomaticus form a well-supported clade sister to the sequences of Cry. niger. Cryptococcomyces carbostomaticus is morphologically similar to Cry. niger, but the latter has a covering stroma without textura prismatica, no basal Covering stroma, and ascospores lack a thick gelatinous sheath. Therefore, Cry. carbostomaticus is considered to be a distinct species.

Figure 4. 

Cryptococcomyces carbostomaticus (HOU 2025/BJTC 2023155, holotype) a ascomata on a twig of Juniperus squamata b, c mature ascomata. Scale bars: 2 mm (a); 1 mm (b, c).

Figure 5. 

Cryptococcomyces carbostomaticus on Juniperus squamata (HOU 2025/BJTC 2023155, holotype) a part of an ascoma in vertical section, covering stroma with hyaline textura prismatica b paraphyses, mature asci with ascospores, and immature ascus. c Liberated ascospores. Scale bars: 100 μm (a); 10 μm (b, c).

Crystallinus (Latin) = crystal, referring to the internal matrix of Covering stroma filled with numerous crystals.

This new species is similar to Cryptococcomyces niger, but differs by an internal matrix of the Covering stroma almost fully filled with crystals.

CHINA, Yunnan Province, Lijiang, Laojunshan, 26.6326°N, 99.7199°E, alt. ca. 3950 m, on twigs of Juniperus squamata (Cupressaceae), 17 Aug. 2023, C.L. Hou, L. Zhuo, and S.Y. Zhao, HOU 2082 (BJTC 2023212, holotype).

Ascomata on twigs, erumpent from bark, scattered, not associated with pale areas. In surface view, ascomata round or slightly irregular, 1000–2000 × 750–1000 µm, black (#000000), opening by radial splits to expose a yellow (#ffd400) to pale orange (#ffa500) hymenium. Lips absent. In median vertical section, covering stroma 80–100 μm thick near the center of ascomata, consisting of an outer layer of carbonized, angular to globose cells and an inner layer of hyaline, thin-walled, angular to globose cells. Basal Covering stroma absent. Internal matrix of Covering stroma 240–260 µm thick, consisting of hyaline, thin-walled, angular cells, with abundant irregular crystals in the matrix. Subhymenium 15–20 µm thick, consisting of hyaline textura porrecta. Paraphyses aseptate, filiform, not branched, slightly curved at tips, 110–130 × 1–2 µm, covered by a thin gelatinous sheath. Asci ripening sequentially, clavate, apex acute, 85–105 × 7–8 µm, stalked, thin-walled, J–, 8-spored. Ascospores aseptate, filiform, tapering towards apex, 40–60 × 1–2 μm, hyaline, with a gelatinous cap.

Conidiomata and zone lines not seen.

CHINA, Yunnan Province, Lijiang, Laojunshan, 26.6319°N, 99.7252°E, alt. ca. 3860 m, on twigs of Juniperus squamata (Cupressaceae), 16 Aug. 2023, C.L. Hou, L. Zhuo, and S.Y. Zhao, HOU 2028 (BJTC 2023158); 26.6318°N, 99.7250°E, alt. ca. 3930 m, on twigs of J. squamata, 16 Aug. 2023, C.L. Hou, L. Zhuo, and S.Y. Zhao, HOU 2030 (BJTC 2023160); 26.6319°N, 99.7244°E, alt. ca. 3890 m, on twigs of J. squamata, 17 Aug. 2023, C.L. Hou, L. Zhuo, and S.Y. Zhao, HOU 2062 (BJTC 2023192).

Known only from Yunnan Province, China.

The multi-locus gene analysis shows that the sequences of Cry. crystallinus form a well-supported clade sister to the sequences of Cryptococcomyces sp. 2. However, the specimens of Cryptococcomyces sp. 2 do not have any mature ascoma; therefore, these two species cannot be compared morphologically. The ITS rDNA sequence similarity between these two species is 92%, so we treat Cry. crystallinus as a separate species. Morphologically, Cry. crystallinus is similar to Cry. niger, but Cry. niger differs by an internal matrix of the Covering stroma lacking crystals.

Figure 6. 

Cryptococcomyces crystallinus (HOU 2082/BJTC 2023212, holotype) a ascomata on a twig of Juniperus squamata b, c mature ascomata. Scale bars: 2 mm (a); 500 μm (b, c).

Figure 7. 

Cryptococcomyces crystallinus on Juniperus squamata (HOU 2082/BJTC 2023212, holotype) a part of an ascoma in vertical section, the internal matrix of Covering stroma filled with numerous crystals b paraphyses, mature asci with ascospores, and immature ascus. c Liberated ascospores with gelatinous cap. Scale bars: 100 μm (a); 10 μm (b, c).

Finland, on bark of Juniperus communis L. (Cupressaceae), Fennia et Lapponia, collected throughout the year (exact date unknown), P. Karsten (A holotype needs to be designated).

Phylogenetically, a non-type sequence of Cry. juniperi clusters with other species of Cryptococcomyces, which also occur on Juniperus spp. Dennis (1958) transferred Coccomyces juniperi to the genus Colpoma based on its slender paraphyses with spirally coiled tips (Dennis 1958). However, species of the genus Colpoma usually have elongated and curved ascomata with a single longitudinal opening slit, whereas Cryptococcomyces juniperi has subglobose ascomata with 3 to 6 triangular flaps (Dennis 1958; Johnston 1991; Lin et al. 2012). Therefore, based on their phylogenetic position, morphological similarities, and host relationship, Cry. juniperi is proposed to belong to the genus Cryptococcomyces.

Niger (Latin) = black, referring to the black ascomata.

This new species is similar to Cryptococcomyces crystallinus, but differs by having an internal matrix of the Covering stroma without crystals.

CHINA, Yunnan Province, Lijiang, Laojunshan, 26.6322°N, 99.7250°E, alt. ca. 3880 m, on twigs of Juniperus squamata (Cupressaceae), 23 Jun. 2020, C.L. Hou, M.J. Guo, and Q.T. Wang, HOU 1625 (BJTC 2020067, holotype).

Ascomata on twigs, scattered, not associated with pale areas. In surface view, ascomata elliptical to round, 800–1000 × 900–1200 µm, black (#000000), erumpent from bark, opening by radial splits to expose a pale yellow (#ffff9d) to yellow (#ffd400) hymenium. Lips absent. In median vertical section, ascomata intracortical. Covering stroma 110–125 μm thick near the center of the ascomata, not extending to the basal Covering stroma, consisting of an outer layer of remains of the host cortex, an inner layer of carbonized, angular to globose cells, and an innermost layer of hyaline angular cells embedded in the hyaline gelatinous matrix. Basal Covering stroma absent. Internal matrix of Covering stroma 90–110 µm thick, consisting of hyaline, thin-walled short hyphae in a gelatinous matrix. Subhymenium 20–30 µm thick, consisting of hyaline textura porrecta. Paraphyses aseptate, filiform, not branched, curled or coiled at tips, 125–150 × 1–2 µm, covered by a thin gelatinous sheath. Asci ripening sequentially, clavate, apex obtuse to acute, 72–95 × 6–8 µm, stalked, thin-walled, J–, 8-spored. Ascospores aseptate, filiform, tapering towards the apex, 30–40 × 1 μm, hyaline.

Conidiomata and zone lines not seen.

CHINA, Yunnan Province, Lijiang, Laojunshan, 26.6322°N, 99.7250°E, alt. ca. 3880 m, on twigs of Juniperus squamata (Cupressaceae), 26 Jul. 2024, C.L. Hou, L. Zhuo, and X.N. Sui, HOU 2303 (BJTC 2024153).

Known only from Yunnan Province, China.

The multi-locus gene analysis indicates that the molecular sequences of Cry. niger form a well-supported clade sister to Cryptococcomyces carbostomaticus. Cry. carbostomaticus is distinguished by presence of a basal Covering stroma and textura prismatica on innermost layer of the covering stroma. Morphologically, Cry. niger is similar to Coccomyces petersii, and both of these two species occur on Juniperus spp. However, the covering stroma of Co. petersii is composed entirely of carbonized globose cells, whereas that of Cry. niger includes an innermost layer of hyaline angular cells embedded in a hyaline gelatinous matrix. Additionally, Co. petersii has larger asci (85–110 × 8–10 µm). The basal Covering stroma of Co. petersii is reduced to a subiculum of dark brown hyphae, while Cry. niger lacks a basal Covering stroma but possesses a well-developed internal matrix within the Covering stroma, consisting of hyaline hyphae.

Figure 8. 

Cryptococcomyces niger (HOU 1625/BJTC 2020067, holotype) a ascomata on a twig of Juniperus squamata b, c mature ascomata. Scale bars: 2 mm (a); 500 μm (b, c).

Figure 9. 

Cryptococcomyces niger on Juniperus squamata (HOU 1625/BJTC 2020067, holotype) a part of an ascoma in vertical section, innermost layer of covering stroma with hyaline angular cells embedded in the hyaline gelatinous matrix b paraphyses, mature asci with ascospores, and immature ascus c liberated ascospores. Scale bars: 100 μm (a); 10 μm (b, c).

Occultus (Latin) = hidden, referring to the ascomata surface being concolorous with the surface of the substrate.

This new species is similar to Cryptococcomyces carbostomaticus, but differs by the absence of hyaline textura prismatica as innermost layer of the covering stroma.

CHINA, Yunnan Province, Kunming, Jiaozi Mountains, 26.0861°N, 102.8492°E, alt. ca. 3810 m, on twigs of Juniperus squamata (Cupressaceae), 23 Jun. 2021, C.L. Hou, M.J. Guo, and H. Zhou, HOU 1861A (BJTC 2021172, holotype).

Ascomata on twigs, scattered, not associated with pale areas. In surface view, ascomata elliptical to round, 1600–2100 × 1400–2100 μm, concolorous with surface of substrate, erumpent through host epidermis, opening by irregular splits to expose pale yellow (#ffff9d) hymenium. Lips absent. In median vertical section, ascomata intracortical. Covering stroma 125–145 μm thick near the center of the ascomata, extending to the basal Covering stroma, consisting of an outer layer of remains of host cortex and an inner layer of carbonized, angular to globose cells. Excipulum present, formed by marginal paraphyses. Basal Covering stroma poorly developed, consisting of carbonized, angular to globose cells. Internal matrix of Covering stroma 95–130 µm thick, consisting of hyaline, thin-walled, angular cells and short hyphae embedded in gelatinous mucus. Subhymenium 20–30 µm thick, consisting of hyaline textura porrecta. Paraphyses aseptate, filiform, not branched, slightly curved at tips, 130–140 × 1–2 µm, covered by a thin gelatinous sheath. Asci ripening sequentially, clavate, apex obtuse to acute, 80–120 × 6–8 μm, stalked, thin-walled, J–, 8-spored. Ascospores aseptate, filiform, 30–40 × 1 μm, hyaline.

Conidiomata and zone lines not observed.

CHINA, Yunnan Province, Lijiang, Laojunshan, 26.6433°N, 99.7675°E, alt. ca. 3500 m, on twigs of Juniperus squamata (Cupressaceae), 16 Jul. 2020, C.L. Hou, M.J. Guo and Q.T. Wang, HOU 1613 (BJTC 2020055); Kunming, Jiaozi Mountains, 26.0841°N, 102.8405°E, alt. ca. 3570 m, on twigs of J. squamata, 23 Jun. 2021, C.L. Hou, M.J. Guo and H. Zhou, HOU 1838 (BJTC 2021149).

Known only from Yunnan Province, China.

Phylogenetically, molecular sequences of Cry. occultus forms a distinct clade with high support values (MLB = 98%, MPB = 97%, PP = 1.00) together with the sequences of Cry. carbostomaticus, Cry. niger, and Cryptococcomyces sp. 1. However, the values of similarity of the ITS rDNA sequences of Cry. occultus with Cry. carbostomaticus, Cry. niger, and Cryptococcomyces sp. 1 are 97%, 96%, and 98%, respectively. Morphologically, Cry. niger differs from Cry. occultus by black, smaller (800–1000 × 900–1200 µm) ascomata, which protrude from the surface of the host; Cry. carbostomaticus differs from Cry. occultus by the presence of hyaline textura prismatica in the innermost layer of the covering stroma. Unfortunately, ascomata in the specimen of Cryptococcomyces sp. 1 are not mature enough to observe microscopic features. Cryptococcomyces occultus is morphologically similar to Coccomyces lijiangensis on Pinus armandii (Pinaceae), but Co. lijiangensis has a well-developed basal Covering stroma (900–1200 µm), and the internal matrix of the Covering stroma consists of hyaline hyphae and numerous crystals variable in shape and size. Therefore, based on phylogenetic and morphological differences, Cry. occultus is designated as a new species. It is the type of the genus Cryptococcomyces because it possesses the most typical traits of ascomata covered by bark.

Figure 10. 

Cryptococcomyces occultus (HOU 1861A/BJTC 2021172, holotype) a ascomata on a twig of Juniperus squamata b, c mature ascomata. Scale bars: 2 mm (a); 500 μm (b); 1 mm (c).

Figure 11. 

Cryptococcomyces occultus on Juniperus squamata (HOU 1861A/BJTC 2021172, holotype) a part of an ascoma in vertical section b paraphyses, mature asci with ascospores, and immature ascus c liberated ascospores. Scale bars: 100 μm (a); 10 μm (b, c).

CHINA, Yunnan Province, Lijiang, Laojunshan, 26.6413°N, 99.7672°E, alt. ca. 3500 m, on twigs of Juniperus sp. (Cupressaceae), 21 Jun. 2021, C.L. Hou, M.J. Guo, and H. Zhou, HOU 1835 (BJTC 2021146).

In the multi-gene phylogenetic tree, the sequences of this undescribed species form a highly supported sister clade with the sequences of Cry. carbostomaticus and Cry. niger. The similarity of the ITS rDNA sequences of Cryptococcomyces sp. 1 with Cry. carbostomaticus and Cry. niger are 98% and 96%, respectively. As mature ascomata were not found in this specimen, it was not possible to conduct detailed morphological studies.

CHINA, Yunnan Province, Lijiang, Laojunshan, 26.6315°N, 99.7249°E, alt. ca. 3900 m, isolated from Juniperus sp. (Cupressaceae), 16 Aug. 2023, C.L. Hou, L. Zhuo, and S.Y. Zhao, CNUCC 2031A31; 26.6316°N, 99.7253°E, alt. ca. 3855 m, isolated from Juniperus sp., 21 Jun. 2021, C.L. Hou, M.J. Guo and H. Zhou, CNUCC 17821; 26.6319°N, 99.7243°E, alt. ca. 3890 m, isolated from Juniperus sp., 17 Aug. 2023, C.L. Hou, L. Zhuo, and S.Y. Zhao, CNUCC 2061B31.

In the multi-gene phylogenetic tree, the molecular sequences of this unnamed species cluster together with the molecular sequence of Cryptococcomyces crystallinus. The ITS rDNA similarity between these two species is 92%. It is worth noting that while processing other ascomata from these specimens, we obtained isolates of this species. However, the observed ascomata did not match the morphological characteristics of this genus. Since multiple isolates of this species were obtained from different specimens, sequencing errors or other potential mistakes have been ruled out. We hypothesize the presence of an undiscovered cryptic species, although no corresponding ascomata have yet been found.

Figure 12. 

Cryptococcomyces sp. 1 (HOU 1835/BJTC 2021146) a immature ascomata on a twig of Juniperus sp. b, c immature ascomata. Scale bars: 1 mm (a); 500 μm (b, c).

Hypoderma rubi (Pers.) DC., in Lamarck & de Candolle, Fl. franç., Edn 3 (Paris) 2: 304. 1805.

Ascomata elliptical to elongated elliptical, black, opening by a longitudinal split, usually subcuticular. Covering stroma formed by mostly dark brown, thick-walled, angular cells, in still closed ascomata with a row of thin-walled, paler cells in the inner half of the wall, along the preformed line of dehiscence. Basal Covering stroma formed prior to the development of the covering stroma or of differentiated asci or paraphyses, comprising several layers of brown, thick-walled, angular cells. Subhymenium consisting of small cells or textura porrecta. Paraphyses filiform, branched or not branched, sometimes with swollen tips, usually coiled at the tips. Asci ripening sequentially, cylindrical to clavate, thin-walled, J–, 8-spored. Ascospores 0–1 septate, variable in shape, hyaline, usually covered by a gelatinous sheath.

Conidiomata , when present, small, subcuticular, circular in outline when viewed from above, lenticular when viewed in vertical section. Upper wall present or not. Lower wall lined with cylindric, solitary conidiogenous cells which proliferate either sympodially or percurrently. Conidia small, not septate, hyaline (Description based on Johnston 1990a).

Hypoderma is a large genus in Rhytismataceae and shares many morphological features with Lophodermium. De Notaris (1847) distinguished Hypoderma and Lophodermium by the shape of the ascospores, placing species with cylindrical to elliptical spores in the former, and those with filiform spores in the latter genus. Johnston (1990a) redefined Hypoderma primarily based on features associated with the pattern of development in the sterile tissues of the ascomata rather than the shape of ascospores. Two species of Hypoderma are known growing on twigs of conifers, Hypoderma abietinum Ellis & Everh. and H. shimanense Y. Suto.

Referring to the host genus Cunninghamia.

This new species is similar to Hypoderma rubi (Pers.) De Not., but differs by a thicker covering stroma and a basal Covering stroma, longer asci and longer ascospores.

CHINA, Anhui Province, Yaoluoping National Nature Reserve, Dachuanling, alt. ca 800 m, on one year old twigs or needles of Cunninghamia lanceolata (Cupressaceae), 9 Sept. 2023, S.J. Wang, L. Zhen, X.Y. Li, and Y.L. Li, L4648 (AAUF 70756, holotype).

Ascomata on one-year twigs and needles, scattered, sometimes 2 to 3 clustered. In surface view, ascomata elliptical to elongated-elliptical, 750–1950 × 275–375 µm, dark brown (#2b180b) to black (#000000), sometimes dark brown in the center, gray (#787870) at the edge, shiny, with a conspicuous black perimeter line, opening by a single longitudinal split. Lips well developed, yellow-brown (#f2d98d). In median vertical section, ascomata subcuticular. Covering stroma 40–60 μm thick near the center of ascomata, gradually thinner towards the edge, connecting to the basal Covering stroma, consisting of an outer layer of host tissue, and an inner layer of dark brown, thick-walled textura angularis. Lips cells 3–4-septate, thin-walled, cylindrical, radially arranged, 20–28 × 3–4 µm, hyaline to yellow-brown. Basal Covering stroma 7–15 µm thick, consisting of carbonized, thick-walled, angular cells. Triangular space in vertical section between the covering stroma and the basal Covering stroma at the margin of the ascoma is filled with hyaline, thin-walled, angular cells. Subhymenium 5–15 µm thick, consisting of hyaline textura porrecta. Paraphyses filiform, sometimes branched, not swollen or slightly swollen at tips, 140–160 × 1–1.2 µm, covered by a thin gelatinous sheath. Asci ripening sequentially, clavate, apex subtruncate or rounded, 70–130 × 12–15 µm, thin-walled, J–, 8-spored. Ascospores aseptate, cylindrical, elliptical or cylindrical-clavate, 14–22 × 3.5–5 μm, hyaline, covered by a ca. 1 μm thick gelatinous sheath.

Conidiomata rounded or elliptical, brown (#48240a), slightly raising the substrate surface, opening by 1–2 ostioles. In median vertical section, conidiomata subcuticular. Upper wall absent. Basal wall poorly developed, black-brown, 3–5 μm thick, consisting of angular cells. Conidia and zone lines not seen.

CHINA, Anhui Province, Yaoluoping National Nature Reserve, Dachuanling, alt. ca. 800 m, on one year old twigs or needles of Cunninghamia lanceolata (Cupressaceae), 9 Sept. 2023, S.J. Wang, L. Zhen, X.Y. Li, and Y.L. Li, L4647 (AAUF 70755).

Known only from Anhui Province, China.

Phylogenetic analysis reveals that, with the exception of H. berberidis, H. minteri, H. caricis, and H. junipericola, other species of Hypoderma are divided into two distant clades. The sequences of the new species, along with several others, form a highly supported clade (MLB = 100%, MPB = 81%, PP = 0.99; Clade 9, Fig. 1). Morphologically, H. cunninghamiicola is similar to the type of Hypoderma, H. rubi, but the latter has a thicker covering stroma (50–80 μm), a thicker basal Covering stroma (10–15 μm), longer asci (110–160 μm) and longer ascospores (15–28 μm) (Johnston 1990a). The host range of H. rubi is broad, and it has been reported on both broadleaved plants and conifers (e.g. Cunninghamia lanceolata). Considering its saprobic nature, these reports are plausible. However, further research incorporating molecular data is required to confirm whether these occurrences truly represent H. rubi or distinct, cryptic species.

Figure 13. 

Hypoderma cunninghamiicola (L4648/AAUF70756, holotype) a ascomata on a twig of Cunninghamia lanceolata b, c mature ascomata. Scale bars: 1000 μm (a); 500 μm (b, c).

Figure 14. 

Hypoderma cunninghamiicola on Cunninghamia lanceolata (L4648/AAUF70756, holotype) a part of an ascoma in vertical section b paraphyses, mature asci with ascospores, and immature ascus c liberated ascospores. Scale bars: 50 μm (a); 20 μm (b, c).

Hypohelion scirpinum (DC.) P.R. Johnst., Mycotaxon 39: 221. 1990.

Ascomata scattered to clustered, subcircular, elliptical or irregular, black, opening by an irregular longitudinal split. Covering stroma formed by dark brown (#2b180b) to black (#000000), thick-walled angular cells, more or less uniform in thickness. Basal Covering stroma absent or formed by carbonized, thick-walled angular cells. Subhymenium consisting of textura intricata. Paraphyses filiform, not branched, with swollen tips. Asci ripening sequentially, clavate, thin-walled, J–, 8-spored. Ascospores 0–1 septate, cylindrical, elliptical or slightly clavate, hyaline, covered by a gelatinous sheath.

Conidiomata , when present, round, dark brown (#2b180b) to black (#000000), with a central ostiole. Conidiogenous cells cylindrical, tapering towards apex, hyaline. Conidia simple, oblong-elliptical to cylindrical, hyaline (Description based on Johnston 1990b).

Hypohelion was established by Johnston (1990b) to accommodate two species, Hy. scirpinum and Hy. parvum P.R. Johnston. Both species are found on members of Cyperaceae Juss. growing in swampy habitats. Hypohelion can be distinguished from other genera by subcuticular ascomata; covering stroma consisting by dark brown, thick-walled, angular cells, more or less uniform in thickness; edge of the ascomata opening without differentiated cells; lacking a basal Covering stroma; and paraphyses with swollen apex (Johnston 1990b). Hypohelion durum Y.R. Lin, C.L. Hou & S.J. Wang (Lin et al. 2004) and Hy. anhuiense Shuang Wang & C.L. Hou (Wang et al. 2014a) were added to this genus subsequently. However, Hy. durum differs from other Hypohelion species based on molecular phylogenetic data, morphology, and substrate. Hypohelion durum should therefore be excluded from the genus Hypohelion (Wang et al. 2014a).

Referring to the name of the location in the Shennongjia forestry region where the type specimen was collected.

This new species is similar to Coccomyces anhuiensis T. Lv & C.L. Hou, but differs by intraepidermal ascomata and ascospores with an apical gelatinous cap, having 4–6 short filament-like appendage on the gelatinous cap.

CHINA, Hubei Province, Shennongjia forestry region, Muyuzhen, 31.4200°N, 110.4030°E, alt. ca. 1560 m, on twigs of Cunninghamia lanceolata (Lamb.) Hook. (Cupressaceae), 20 Jul. 2018, C.L. Hou & T. Lv. HOU 1342A (BJTC 2018037, holotype).

Ascomata on young and dead twigs, scattered, not associated with pale areas. In surface view, ascomata wide elliptical to irregular elliptical, 650–950 × 350–500 µm, black (#000000), or black in the center and gray (#787870) towards the margin, shiny, with black perimeter line, opening by an irregular, longitudinal, 3-teethed split. Lips absent. In median vertical section, ascomata intraepidermal. Covering stroma 30–35 μm thick near the center of ascomata, extending to the basal Covering stroma, consisting of an outer layer of host cuticle and an inner layer of carbonized, thick-walled angular cells. Basal Covering stroma 15–20 µm thick, consisting of carbonized, thick-walled, angular cells. Triangular space visible in vertical section between the covering stroma and the basal Covering stroma at margin of ascoma filled with thin-walled angular, globose cells. Subhymenium 10–15 µm thick, consisting of hyaline textura intricata. Excipulum well-developed, formed by marginal paraphyses. Paraphyses aseptate, filiform, not branched, not swollen at tips, 120–140 × 1–2 µm. Asci ripening sequentially, clavate, apex bluntly pointed, 70–90 × 6–10 µm, thin-walled, J–, 8-spored. Ascospores aseptate, clavate, 35–45 × 2–3 μm, hyaline, multi-guttulate when immature, covered by thin gelatinous sheaths, with a gelatinous cap at the tip of mature ascospores, with 4–6 short filament-like appendages on each gelatinous cap.

see Notes. Zone lines infrequent, diffuse, black.

Known only from Hubei Province, China.

Based on the phylogenetic analysis, Hy. shennongjianum clusters with the type of the genus Hypohelion, Hy. scirpinum, as well as Hy. anhuiense, with weak support (Clade 5, Fig. 1). Morphologically, Hy. shennongjianum shares clavate ascospores with other species of Hypohelion, but the shape of its ascomata is distinct from other Hypohelion species and resembles that of Coccomyces anhuiensis. However, unlike Co. anhuiensis, Hy. shennongjianum has intraepidermal ascomata and ascospores carry a gelatinous cap at the tops, bearing 4–6 short filament-like appendages on the gelatinous cap. Considering both its phylogenetic position and morphological characteristics, this new species should be placed in the genus Hypohelion.

A probable asexual morph was observed in association with Hy. shennongjianum. The conidiomata are scattered, occasionally confluent, elliptical, reddish brown (#68271a), and 100–200 × 200–350 µm in size. In vertical section, the conidiomata are intraepidermal, 80–100 µm deep, with an upper layer 25–30 µm thick, composed of host cuticle and carbonized angular to globose cells, and a basal layer 15–18 µm thick, consisting of similar carbonized cells. Conidiogenous cells and conidia were not observed. Sequencing of the conidiomata was attempted but unsuccessful, so molecular data does not currently support the connection.

Figure 15. 

Hypohelion shennongjianum (HOU 1342A/BJTC 2018037, holotype) a ascomata on a twig of Cunninghamia lanceolata b zone line c, d mature ascomata e conidiomata. Scale bars: 500 μm (a); 100 μm (b); 200 μm (c–e).

Figure 16. 

Hypohelion shennongjianum on Cunninghamia lanceolata (HOU 1342A /BJTC 2018037, holotype) a part of an ascoma in vertical section b conidioma in vertical section c paraphyses, mature asci with ascospores, and immature ascus d liberated ascospores with apical gelatinous cap. Scale bars: 50 μm (a, b); 10 μm (c); 20 μm (d).

Labium (Latin) = lip, validus (Latin) = strong, referring to the well-developed lips of ascomata.

This new genus is similar to Hypoderma, but differs from Hypoderma by broadly elliptical ascomata and filiform ascospores.

Labivalidus cunninghamiae Lan Zhuo & C.L. Hou, described below.

Ascomata often scattered, elliptical to broadly elliptical, black (#000000), opening by a single longitudinal split. Lips well-developed, creamy white(#fffeea). Ascomata intraepidermal. Covering stroma consisting of carbonized, thick-walled, angular to globose cells. Basal Covering stroma moderately to well developed, consisting of carbonized, thick-walled, angular to globose cells. Internal matrix of Covering stroma absent. Paraphyses filiform, not branched, not swollen or swollen at tips. Asci ripening sequentially, cylindrical, rostrate at apex at maturity, thin-walled, J–, 8-spored. Ascospores aseptate, filiform, hyaline, covered by a gelatinous sheath.

Conidiomata and zone lines not seen.

In the context of the present study, molecular data for the species described as Lophodermium jianchuanense have been obtained. Phylogenetic analyses shows that the molecular sequences of Lo. jianchuanense and the new species Labivalidus cunninghamiae (described below) form a distinct clade (Clade 10, Fig. 1). Both species are distantly related to the type species of the genus Lophodermium, Lo. arundinaceum (Schrad.) Chevall., as well as the species of Lophodermium on needles of conifers, indicating that La. cunninghamiae and Lo. jianchuanense should not be classified in the genus Lophodermium.

Morphologically, the ascomata of both Lo. jianchuanense and La. cunninghamiae have conspicuous, creamy-colored lips, which are similar to some species of the genus Hypoderma. However, species in the genus Hypoderma s. str. are usually saprotrophic, with a wide host range, their ascomata are often elliptical to elongate in shape, and ascospores elliptical to cylindrical (De Notaris 1847; Powell 1974; Cannon and Minter 1986; Johnston 1990a), whereas Lo. jianchuanense and La. cunninghamiae have a narrow host range, known only from Cupressaceae, have broadly elliptical ascomata and filiform ascospores. Furthermore, Lo. jianchuanense and La. cunninghamiae are also distant from the type of Hypoderma in the phylogenetic tree, suggesting that they should not be classified in Hypoderma.

Considering the phylogenetic and morphological evidence, it is necessary to establish a new genus to accommodate Lo. jianchuanense and La. cunninghamiae. Lophodermium jianchuanense is transferred to Labivalidus as a new combination, La. jianchuanensis.

Referring to the host genus Cunninghamia.

This new species is similar to Labivalidus jianchuanensis, but differs in having larger ascomata, larger ascospores, and paraphyses that are conspicuously swollen at their tips.

CHINA, Anhui Province, Anqing, Yuexi County, Wenao Forest Farm, 30.8050°N, 116.0885°E, alt. ca. 1020 m, on twigs of Cunninghamia lanceolata (Cupressaceae), 13 Apr. 2024, C.L. Hou, L. Zhuo, and X.N. Sui, HOU 2173A (BJTC 2024033, holotype).

Ascomata on young dead twigs, scattered, sometimes 2–3 clustered. In surface view, ascomata elliptical to broadly elliptical, 900–1600 × 480–880 μm, black (#000000), opening by a longitudinal split. Lips well developed, creamy white (#fffeea). In median vertical section, ascomata intraepidermal. Covering stroma 50–90 μm thick near the center of the ascomata, extending to the basal Covering stroma, consisting of an outer layer of host cuticle, and an inner layer of carbonized, thick-walled, angular to globose cells. Lip cells septate, cylindrical, 6–10 × 2–4 μm, hyaline. Basal Covering stroma 20–30 µm thick, consisting of carbonized, thick-walled, angular to globose cells. A space triangular in vertical section between the covering stroma and the basal Covering stroma at the margin of the ascoma is filled with thin-walled, hyaline cells. Subhymenium 20–30 µm thick, consisting of textura intricata. Paraphyses filiform, not branched, conspicuously swollen to 2–3 μm diam. at their tips, 150–195 × 1 µm, covered by a thin gelatinous sheath. Asci ripening sequentially, cylindrical, with rostrate apex, 130–180 × 13–15 μm, thin-walled, J–, 8-spored. Ascospores aseptate, filiform, 100–125 × 3–4 μm, hyaline, covered by a 1–2 μm thick, gelatinous sheath.

Conidiomata and zone lines not seen.

CHINA, Anhui Province, Anqing, Yuexi County, Yaoluoping Nature Reserve, 30.8050°N, 116.0885°E, alt. ca. 1020 m, on twigs of Cunninghamia lanceolata (Cupressaceae), 13 Apr. 2024, C.L. Hou, L. Zhuo, and X.N. Sui, HOU 2166 (BJTC 2024026).

Known only from Anhui Province, China.

In the phylogenetic tree, the molecular sequences of Labivalidus cunninghamiae form a clade sister to La. jianchuanensis. Labivalidus jianchuanensis differs from La. cunninghamiae by having smaller ascomata (500–750(–920) µm × 400–520 µm), smaller ascospores (65–90 µm × 1–1.5(–2) µm), and tips of paraphyses that are not swollen.

Figure 17. 

Labivalidus cunninghamiae (HOU 2173A/BJTC 2024033, holotype) a ascomata on a twig of Cunninghamia lanceolata b, c Mature ascomata. Scale bars: 2 mm (a); 500 μm (b, c).

Figure 18. 

Labivalidus cunninghamiae on Cunninghamia lanceolata (HOU 2173A /BJTC 2024033, holotype) a part of an ascoma in vertical section, lips well developed b paraphyses, mature asci with ascospores, and immature ascus c liberated ascospores. Scale bars: 100 μm (a); 10 μm (b); 20 μm (c).

CHINA, Yunnan Province, Jianchuan, Laojunshan, alt. ca. 3400 m, on Juniperus formosana Hayata (Cupressaceae), 25 Jul. 2001, C.L. Hou, M. Piepenbring, Z.L. Yang, & R. Kirschner 104 (HMAS, holotype).

CHINA, Yunnan Province, Lijiang, Laojunshan, 26.6319°N, 99.7252°E, alt. ca. 3855 m, on needles and twigs of Juniperus squamata (Cupressaceae), 21 Jun. 2021, C.L. Hou, M.J. Guo, and H. Zhou, HOU 1781B (BJTC 2021092); 26.6314°N, 99.7247°E, alt. ca. 3850 m, on needles and twigs of J. squamata, 21 Jun. 2021, C.L. Hou, M.J. Guo, and H. Zhou, HOU 1815A (BJTC 2021126); 26.6425°N, 99.7678°E, alt. ca. 3500 m, on needles and twigs of J. squamata, 17 Aug. 2023, C.L. Hou, L. Zhuo, and S.Y. Zhao, HOU 2023 (BJTC 2023153); 26.6425°N, 99.7678°E, alt. ca. 3500 m, on needles and twigs of J. squamata, 17 Aug. 2023, C.L. Hou, L. Zhuo, and S.Y. Zhao, HOU 2024 (BJTC 2023154).

Hou et al. (2005) described Lophodermium jianchuanense on Juniperus formosana in the genus Lophodermium. In the phylogenetic tree, the molecular sequences of Lo. jianchuanense form a clade sister to La. cunninghamiae and distant from Lo. arundinaceum, the type species of Lophodermium. Based on this phylogenetic position and morphological similarity, we transfer Lo. jianchuanense to the genus Labivalidus, the epithet has been adjusted to agree with the gender of the new genus name.

Figure 19. 

Labivalidus jianchuanensis (HOU 1781B/BJTC 2021092) a ascomata on needles of Juniperus squamata b, c mature ascomata on a twig or a needle of Juniperus squamata. Scale bars: 1 mm (a); 500 μm (b); 200 μm (c).

Referring to the morphologically similar genus Therrya.

This new genus is similar to Therrya, but Neotherrya differs in having well-developed excipulum formed by marginal paraphyses, internal matrix of Covering stroma consisting of hyaline hyphae, and filiform, fusiform, or cylindrical ascospores.

Neotherrya circinata Lan Zhuo & C.L. Hou, described below.

Ascomata on twigs of conifers, scattered to clustered, circular, sessile, usually black, opening by irregular splits. Covering stroma formed by dark brown (#2b180b) to black (#000000), thick-walled angular cells. Basal Covering stroma usually present, consisting of carbonized, thick-walled, angular cells. Internal matrix of Covering stroma usually well developed, consisting of hyaline hyphae, filled or not filled with crystals. Subhymenium consisting of textura intricata or hyaline cells. Paraphyses filiform, not branched, with swollen tips. Asci ripening sequentially, clavate, thin-walled, J–, 8-spored or 4-spored. Ascospores mostly septate, filiform, fusiform or cylindrical, hyaline, covered or not covered by a gelatinous sheath.

Some of the morphological characteristics of members in Neotherrya are similar to those in Therrya, but species of Neotherrya differs by a well-developed excipulum formed by marginal paraphyses, an internal matrix of Covering stroma consisting of hyaline hyphae and cylindrical ascospores. Phylogenetic analyses shows that sequences of Neotherrya and Therrya form two separate clades. Sequences of Neotherrya (Clade 6, Fig. 1) are distant from the type of Therrya, Th. pini (Alb. & Schwein.) Höhn. Based on differences of morphological features and the position in the phylogenetic tree, we herein establish a new genus to accommodate four new species and one new combination described below.

CHINA, Yunnan Province, Laojunshan, alt. ca. 2400 m, on twigs of Abies sp. (Pinaceae), 25 Jul. 2001, C.L. Hou, M. Piepenbring, R. Kirschner, and Z.L. Yang 103 (AAUF 90036).

CHINA, Yunnan Province, Lijiang, Laojunshan, alt. ca. 3500 m, on twigs of Abies sp. (Pinaceae), 11 Jul. 2007, C.L. Hou, HOU 447.

Hou and Piepenbring (2007) described Therrya abieticola on Abies sp. in the genus Therrya Sacc. because the shapes of asci, ascospores, and paraphyses of Th. abieticola are similar to those of the type Th. pini (Alb. & Schwein.) Höhn. (Reid and Cain 1961; Hou and Piepenbring 2007). However, Hou and Piepenbring (2009) mentioned that Th. abieticola differs from the known species of Therrya by having aseptate ascospores.

Our phylogenetic analysis shows that sequences of Th. abieticola form a well-supported clade (MLB = 100%, MPB = 91%, PP = 1.00) together with sequences of N. nematoidea and are distantly related to type species of Therrya, Th. pini. Based on morphological characteristics and phylogenetic analyses, Th. abieticola is transferred here to the new genus Neotherrya. For a detailed description of this species see Hou and Piepenbring (2007).

Catilliformis (Latin) = plate-shaped, referring to the shape of ascomata.

This new species is distinguished from other Neotherrya species by lacking an internal matrix of the Covering stroma.

CHINA, Yunnan Province, Lijiang, Laojunshan, 26.6323°N, 99.7252°E, alt. ca. 3880 m, on twigs of Abies georgei (Pinaceae), 16 Jul. 2020, C.L. Hou, M.J. Guo, and Q.T. Wang, HOU 1608A (BJTC 2020049, holotype).

Ascomata on twigs, slightly erumpent from the bark, scattered or aggregated, not associated with pale areas. In surface view, ascomata round to irregular, 550–950 × 350–750 µm, black (#000000), opening by irregular splits to expose an orange (#ffa500) hymenium. Lips absent. In median vertical section, covering stroma 20–40 μm thick near the center of ascomata, extending to the basal Covering stroma, consisting of an outer layer of carbonized, angular to globose cells and an inner layer of hyaline, angular to globose cells close to the opening. Excipulum well-developed, formed by marginal paraphyses. Basal Covering stroma 15–25 µm thick, easily separable from the hymenium layer when observed under the microscope, consisting of carbonized, thick-walled, angular cells. Internal matrix of Covering stroma absent. Subhymenium 25–30 µm thick, consisting of hyaline, globose cells. Paraphyses aseptate, filiform, not branched, swollen to 2–3 µm at tips, 130–150 × 1–2 µm, covered by a thin gelatinous sheath. Asci ripening sequentially, clavate, apex obtuse, 110–130 × 12–15 µm, thin-walled, J–, 4-spored. Ascospores 1–8-septate, cylindrical, 12–15 × 6–7 μm, hyaline, without gelatinous sheaths.

Conidiomata and zone lines not seen.

CHINA, Yunnan Province, Lijiang, Laojunshan, 26.6323°N, 99.7252°E, alt. ca. 3880 m, on twigs of Abies georgei (Pinaceae), 26 Jul. 2024, C.L. Hou, L. Zhuo, and X.N. Sui, HOU 2304 (BJTC 2024154); 26.6357°N, 99.7294°E, alt. ca. 3850 m, on twigs of A. georgei, 17 Aug. 2023, C.L. Hou, L. Zhuo, and S.Y. Zhao, HOU 2097 (BJTC 2023227).

Known only from Yunnan Province, China.

In the phylogenetic tree, sequences of N. catilliformis form a well-supported clade (MLB = 100%, MPB = 97%, PP = 1.00) with N. circinata, but the latter has a well-developed internal matrix in the Covering stroma, a black epithecium formed by curled, coiled paraphyses, and 8-spored asci.

Figure 20. 

Neotherrya catilliformis (HOU 1608A/BJTC 2020049, holotype) a ascomata on a twig of Abies georgei b, c mature ascomata. Scale bars: 3 mm (a); 200 μm (b); 500 μm (c).

Figure 21. 

Neotherrya catilliformis on Abies georgei (HOU 1608A/BJTC 2020049, holotype) a part of an ascoma in vertical section b paraphyses, mature asci with ascospores, and immature ascus c liberated ascospores. Scale bars: 50 μm (a); 10 μm (b, c).

From circinatus (Latin) = to make round, referring to the curled tips of the paraphyses.

This new species is similar to Neotherrya catilliformis, but differs by its well-developed internal matrix of the Covering stroma, curled and coiled tips of paraphyses, and 8-spored asci.

CHINA, Yunnan Province, Lijiang, Laojunshan, alt. ca. 3800 m, on twigs of Abies georgei (Pinaceae), 25 Jun. 2011, C.L. Hou, HOU 883 (BJTC 2011041, holotype).

Ascomata on twigs, slightly erumpent from bark, scattered, not associated with pale areas. In surface view, ascomata round to irregular, 800–1000 µm in diam., black (#000000), opening by irregular splits to expose a tangerine yellow (#ffb700) hymenium. Lips absent. In median vertical section, covering stroma 65–85 μm thick near the center of ascomata, extending to the basal Covering stroma, consisting of an outer layer of carbonized, angular cells and an inner layer of hyaline, angular cells. Excipulum well-developed, formed by marginal paraphyses. Basal Covering stroma 25–35 µm thick, consisting of an outer layer of carbonized, angular cells and an inner layer of hyaline, angular cells. Internal matrix of Covering stroma well-developed, consisting of hyaline hyphae, filled with irregular crystals. Subhymenium 10–15 µm thick, consisting of textura intricata. Paraphyses aseptate, filiform, not branched, curled and coiled, slightly swollen at their tips, forming the black epithecium, 110–140 × 2–2.5 µm. Asci ripening sequentially, clavate, apex obtuse, 75–125 × 10–17 µm, thin-walled, J–, 8-spored. Ascospores initially non-septate, with up to 7 septa when mature, cylindrical, acute at both ends, 23–38 × 2–4 μm, hyaline, covered by a 2–3 µm thick gelatinous sheath.

Conidiomata and zone lines not seen.

CHINA, Yunnan Province, Lijiang, Laojunshan, 26.6317°N, 99.7250°E, alt. ca. 3280 m, on twigs of Abies georgei (Pinaceae), 17 Jul. 2021, C.L. Hou, M.J. Guo, and Q.T. Wang, HOU 1587 (BJTC 2020026); 26.6308°N, 99.7165°E, alt. ca. 4000 m, on twigs of A. georgei, 21 Jun. 2021, C.L. Hou, M.J. Guo, and H. Zhou, HOU 1824 (BJTC 2021135).

Known only from Yunnan Province, China.

Phylogenetically, sequences of Neotherrya circinata form a well-supported clade (MLB = 100%, MPB = 97%, PP = 1.00) with N. catilliformis, but the latter lacks an internal matrix of the Covering stroma and has 4-spored asci. Morphologically, the new species is similar to Neotherrya nematoidea, but N. nematoidea has well- developed periphysoids, and nematode-like ascospores.

Figure 22. 

Neotherrya circinata (HOU 883/BJTC 2011041, holotype) a ascomata on a twig of Abies georgei b, c mature ascomata. Scale bars: 1 mm (a); 300 μm (b, c).

Figure 23. 

Neotherrya circinata on Abies georgei (HOU 883/BJTC 2011041, holotype) a part of an ascoma in vertical section b paraphyses with curled and coiled tips, mature asci with ascospores, and immature ascus c liberated ascospores. Scale bars: 100 μm (a); 10 μm (b, c).

Nematoidea (Latin) = nematode-like, refers to the shape of the released ascospores.

This new species is distinguished from Neotherrya abieticola by N. nematoidea having filiform ascospores with 1–3-septa.

CHINA, Yunnan Province, Lijiang, Laojunshan, 26.6323°N, 99.7252°E, alt. ca. 3880 m, on twigs of Abies georgei (Pinaceae), 16 Jul. 2020, C.L. Hou, M.J. Guo, and Q.T. Wang, HOU 1598B (BJTC 2020038, holotype).

Ascomata on twigs, erumpent from bark, scattered, not associated with pale areas. In surface view, ascomata round to irregular, 750–1000 µm, black (#000000), opening by irregular splits to expose a pale yellow (#ffff9d) hymenium. Lips absent. In median vertical section, covering stroma 40–60 μm thick near the center of ascomata, extending to the basal Covering stroma, consisting of carbonized, angular to globose cells. Periphysoids present. On inner surface of thecovering layer close to opening, a layer formed by periphysoids embedded in gelatinous matrix. Excipulum well-developed, formed by marginal paraphyses. Basal Covering stroma absent. Internal matrix of Covering stroma well-developed, consisting of hyaline hyphae and angular to globose cells. Subhymenium 15–25 µm thick, consisting of hyaline, angular cells. Paraphyses aseptate, filiform, not branched, swollen to 2–3 µm diam. at tips, 160–190 × 1–2 µm, covered by a thin gelatinous sheath. Asci ripening sequentially, clavate, apex obtuse, 110–170 × 10–13 µm, thin-walled, J–, 4-spored. Ascospores 1–3-septate, usually 3-septate, with shapes of nematode, tapering at both ends, 65–100 × 2–3 μm, hyaline, without gelatinous sheaths.

Conidiomata and zone lines not seen.

CHINA, Yunnan Province, Lijiang, Laojunshan, 26.6323°N, 99.7252°E, alt. ca. 3880 m, on twigs of Abies georgei (Pinaceae), 26 Jul. 2024, C.L. Hou, L. Zhuo, and X.N. Sui, HOU 2305 (BJTC 2024155).

Known only from Yunnan Province, China.

Neotherrya nematoidea is closely related to N. abieticola in the phylogenetic tree, but N. abieticola has fusiform ascospores that are much shorter (30–50 × 2.5–4.5 µm) than the ascospores of N. nematoidea (65–100 × 2–3 μm) and lacks periphysoids.

Figure 24. 

Neotherrya nematoidea (HOU 1598B/BJTC 2020038, holotype) a ascomata on a twig of Abies georgei b, c mature ascomata. Scale bars: 2 mm (a); 1 mm (b); 500 μm (c).

Figure 25. 

Neotherrya nematoidea on Abies georgei (HOU 1598B /BJTC 2020038, holotype) a part of an ascoma in vertical section, periphysoids present, embedded in gelatinous matrix b paraphyses, mature asci with ascospores, and immature ascus c liberated ascospores. Scale bars: 100 μm (a); 10 μm (b, c).

Referring to the host genus Pinus.

This new species is distinguished from other Neotherrya species by its aseptate, cylindrical ascospores.

CHINA, Yunnan Province, Lijiang, Shangri-la, Bilahai, alt. ca. 3540 m, on twigs of Pinus densata Mast. (Pinaceae), 27 Jun. 2011, C.L. Hou, HOU 919 (BJTC 2011077, holotype).

Ascomata on twigs, erumpent from bark, scattered, not associated with pale areas. In surface view, ascomata round to irregular, 480–900 µm, dark gray (#373737) to dark brown (#2b180b), opening by irregular splits to expose a black (#000000) hymenium. Lips absent. In median vertical section, covering stroma 40–60 μm thick near the center of ascomata, extending to the basal Covering stroma, consisting of the outer remains of the epidermis with the cuticle, an inner layer of carbonized, thick-walled, angular to globose cells, and an innermost layer of hyaline, angular cells. Excipulum well-developed, formed by marginal paraphyses. Basal Covering stroma 8–10 μm thick, consisting of dark brown hyphae and carbonized, thick-walled angular cells. Internal matrix of Covering stroma well-developed, consisting of hyaline, short hyphae. Subhymenium 10–15 µm thick, consisting of textura intricata. Paraphyses aseptate, filiform, not branched, swollen to 3–7 µm at their tips, agglutinated to form a dark epithecium, 120–165 × 2–2.5 µm, covered by a thin gelatinous sheath. Asci ripening sequentially, clavate, apex obtuse-rounded, 100–150 × 8–11 µm, thin-walled, J–, 8-spored. Ascospores aseptate, cylindrical to fusiform, tapering at both ends, 65–100 × 2–3 μm, hyaline, pluriguttulate, without gelatinous sheaths.

Conidiomata and zone lines not seen.

Known only from Yunnan Province, China.

In the phylogenetic tree, Neotherrya pinicola is closely related to four species, N. abieticola, N. catilliformis, N. circinata, and N. nematoidea. These five species form a clade with high support values (MLB = 100%, MPB = 100%, PP = 1.00). Morphologically, N. pinicola has sessile ascomata with a well-developed excipulum like the other four species. Based on the phylogenetic analysis and morphological characteristics, N. pinicola should be placed in the genus Neotherrya. Neotherrya pinicola differs from the other four species by the cylindrical to fusiform, aseptate ascospores. Therefore, N. pinicola is proposed as a distinct species.

Figure 26. 

Neotherrya pinicola (HOU 919/BJTC 2011077, holotype) a ascomata on a twig of Pinus densata b, c mature ascomata. Scale bars: 2 mm (a); 500 μm (b, c).

Figure 27. 

Neotherrya pinicola on Pinus densata (HOU 919/BJTC 2011077, holotype) a part of an ascoma in vertical section b paraphyses, mature asci with ascospores, and immature ascus c liberated ascospores. Scale bars: 100 μm (a); 10 μm (b, c).

Referring to morphologically similar species of Coccomyces.

This new genus is similar to Coccomyces, but lacks a basal Covering stroma.

Pseudococcomyces yunnanensis Lan Zhuo & C.L. Hou, described below.

Ascomata on twigs of Larix sp., erumpent from bark, scattered, round or slightly irregular, surface wrinkled, black (#000000), opening by radial or irregular splits. In median vertical section, covering stroma well developed. Basal Covering stroma absent. Internal matrix of Covering stroma present, consisting of hyaline, thin-walled, interwoven hyphae. Subhymenium consisting of thin-walled, angular cells. Paraphyses filiform, coiled, interwoven at their tips. Asci clavate, thin-walled, J–, 8-spored. Ascospores aseptate, filiform, hyaline, covered by a thick gelatinous sheath.

Conidiomata and zone lines not seen.

Based on the phylogenetic analysis, sequences of Pseudococcomyces form a well-supported clade (MLB = 100%, MPB = 99%, PP = 1.00; Clade 8, Fig. 1), and appear to be closely related to Stipamyces, but ascomata of Stipamyces are stalked. The ascomata of the type species of the new genus is morphologically similar to ascomata of species of the genus Coccomyces, but the sequences of species in the new genus on the phylogenetic tree are distant from the sequence of the type species of the genus Coccomyces (Co. tumidus). Based on morphological and phylogenetic differences, we describe Pseudococcomyces as a new genus.

Referring to the name of the province (Yunnan) where the specimen was collected.

This new species is similar to Coccomyces irretitus Sherwood, but Pseudococcomyces yunnanensis has paraphyses that are coiled, interwoven at their tips and lacks interwoven hyaline periphysoids.

CHINA, Yunnan Province, Lijiang, Laojunshan, 26.6434°N, 99.7676°E, alt. ca. 3930 m, on twigs of Larix speciosa W. C. Cheng & Y. W. Law (Pinaceae), 16 Jul. 2020, C.L. Hou, M.J. Guo, and H. Zhou, HOU 1574 (BJTC 2020012, holotype).

Ascomata on twigs, erumpent, scattered, not associated with pale areas. In surface view, ascomata round to irregularly elongate, 750–1000 µm diam., black (#000000), erumpent from bark, opening by radial splits to expose a yellow (#ffd400) hymenium. Lips absent. In median vertical section, covering stroma 50–70 μm thick near the center of the ascomata, not extending to the base, consisting of an outer layer of remains of the host cortex, an inner layer of carbonized, angular to globose cells, and an innermost layer of pigmented angular to globose cells. Basal Covering stroma absent. Internal matrix of Covering stroma 250–300 µm thick, consisting of hyaline, thin-walled, angular cells and interwoven short hyphae. Subhymenium 30–50 µm thick, consisting of thin-walled, angular cells. Paraphyses aseptate, filiform, strongly circinate, not swollen at tips, 145–160 × ca. 1 µm. Asci ripening sequentially, clavate, apex bluntly pointed, 105–155 × 12–18 µm, stalked, thin-walled, J–, 8-spored. Ascospores aseptate, filiform-clavate, tapering towards base, 40–55 × 1–2 μm, hyaline, covered by a 3–5 μm thick gelatinous sheath.

Conidiomata and zone lines not seen.

CHINA, Yunnan Province, Lijiang, Laojunshan, 26.6434°N, 99.7676°E, alt. ca. 3930 m, on twigs of Larix speciosa (Pinaceae), 26 Jul. 2024, C.L. Hou, L. Zhuo, and X.N. Sui, HOU 2306 (BJTC 2024156).

Known only from Yunnan Province, China.

In the phylogenetic tree, the sequences of P. yunnanensis form a distinct clade. Morphologically, P. yunnanensis is closely related to Co. irretitus; because both species grow on twigs of Larix spp. However, Co. irretitus has branched, netlike interwoven hyaline periphysoids immersed in a gel at the inner side of the covering stroma, and the tips of its paraphyses are weakly circinate (Sherwood 1980). Therefore, P. yunnanensis is considered to be a new species.

Figure 28. 

Pseudococcomyces yunnanensis (HOU 1574/BJTC 2020012, holotype) a ascomata on a twig of Larix speciosa b, c mature ascomata. Scale bars: 2 mm (a); 500 μm (b, c).

Figure 29. 

Pseudococcomyces yunnanensis on Larix speciosa (HOU 1574/BJTC 2020012, holotype) a part of an ascoma in vertical section b paraphyses, mature asci with ascospores, and immature ascus c liberated ascospores. Scale bars: 100 μm (a); 10 μm (b, c).

Stipa- from stipes (Latin) = stalk, referring to the stalked ascomata.

This new genus is similar to Tryblidiopsis, but differs in having aseptate ascospores.

Stipamyces pinicola (R.H. Lei & C.L. Hou) Lan Zhuo & C.L. Hou

Ascomata on twigs of Pinus spp., erumpent, stalked, scattered or aggregate, round or slightly irregular, black, opening by irregular splits. In median vertical section, covering stroma well developed. Basal Covering stroma absent. Internal matrix of Covering stroma present, consisting of hyaline, thin-walled, interwoven hyphae. Subhymenium consisting of small, hyaline cells. Paraphyses filiform, circinate at tips. Asci clavate, thin-walled, J–, 8-spored. Ascospores aseptate, long-fusiform, hyaline, not covered by a thick gelatinous sheath.

Conidiomata and zone lines not seen.

Based on the phylogenetic analysis, the molecular sequences of Stipamyces spp. form a well-supported clade (MLB = 100%, MPB = 82%, PP = 1.00; Clade 7, Fig. 1), and appear to be closely related to Pseudococcomyces yunnanensis. Pseudococcomyces yunnanensis differs from Stipamyces spp. by sessile ascomata. Species within the genus Tryblidiopsis also possess stalked ascomata, but the ascospores of Tryblidiopsis spp. are typically septate. Furthermore, in the phylogenetic tree, the sequences of species of these two genera are distant. Thus, Stipamyces is treated as a new genus.

Referring to the host, Pinus massoniana Lamb. (Pinaceae).

This new species is similar to Stipamyces pinicola, but the ascomata of Stipamyces massonianae have longer stalks, and paraphyses are sometimes branched at their tips.

CHINA, Anhui Province, Anqing, Yuexi County, alt. ca. 1000 m, on twigs of Pinus massoniana, 20 Apr. 2015, C.L. Hou, HOU 1215 (BJTC 2015001, holotype).

Ascomata on twigs, aggregated in groups of two to five, not associated with pale areas. In surface view, ascomata round to irregular, 875–1925 µm in diam., 1000–1600 µm high, black (#000000), erumpent from bark, opening by irregular splits to expose a yellow (#ffd400) hymenium. Lips absent. In median vertical section, covering stroma 30–50 μm thick near the center of the ascomata, extending to the base, consisting of an outer layer of remains of the host cortex, an inner layer of carbonized, angular cells, and an innermost layer of hyaline angular cells. Periphysoids on the inner surface of thecovering layer close to the opening, another layer formed by paraphysoids embedded in a gelatinous matrix. Basal Covering stroma absent. Internal matrix of Covering stroma well-developed, consisting of hyaline, interwoven hyphae. Subhymenium 65–80 µm thick, consisting of small, hyaline cells. Paraphyses aseptate, filiform, circinate, sometimes branched at tips, 100–145 × ca. 1 µm. Asci ripening sequentially, clavate, slightly truncate at the apex, 40–130 × 4–14 µm, stalked, thin-walled, J–, 8-spored. Ascospores aseptate, long-fusiform, acute at both ends, 25–40 × 2–4 μm, hyaline, not covered by a gelatinous sheath.

Conidiomata and zone lines not seen.

Known only from Anhui Province, China.

The phylogenetic analysis shows that S. massonianae is congeneric with S. pinicola, but the latter has shorter stalks on ascomata, a thinnercovering layer, and unbranched tips of paraphyses. The sequence similarity of ITS rDNA between these species is 93%, indicating that S. massonianae is a distinct species.

Figure 30. 

Stipamyces massonianae (HOU 1215/BJTC 2015001, holotype) a ascomata on a twig of Pinus massoniana b, c mature ascomata. Scale bars: 3 mm (a); 1 mm (b, c).

Figure 31. 

Stipamyces massonianae on Pinus massoniana (HOU 1215/BJTC 2015001, holotype) a part of an ascoma in vertical section, periphysoids present, embedded in gelatinous matrix b paraphyses, mature asci with ascospores, and immature ascus c liberated ascospores. Scale bars: 200 μm (a); 25 μm (b); 10 μm (c).

CHINA, Yunnan Province, Lijiang, Tiejiashan, alt. ca. 2000 m, on twigs of Pinus armandii (Pinaceae), 11 Jul. 2007, C.L. Hou, HOU 486A (BJTC 201202, holotype); HOU 486B (BJTC 201212, isotype).

CHINA, Anhui Province, Yuexi, Miaodaoshan, on twigs of Pinus taiwanensis Hayata (Pinaceae), 11 Jul. 2007, C.L. Hou, HOU 538 (BJTC 201252); CHINA, Yunnan Province, Lijiang, Laojunshan, 26.6663°N, 99.9388°E, alt. ca. 2345 m, on twigs of Pinus yunnanensis Franch. (Pinaceae), 16 Jul. 2020, C.L. Hou, HOU 1618 (BJTC 2020060).

Lei et al. (2013) placed Co. pinicola within the genus Coccomyces based on morphological characteristics with species of Coccomyces. Coccomyces pinicola clustered weakly with Colpoma quercinum in their study. After incorporating sequences from additional specimens, our phylogenetic analysis indicates that these sequences of Co. pinicola form a well-supported clade (MLB = 100%, MPB = 82%, PP = 1.00) together with sequences of S. massonianae, and are only distantly related to Col. quercinum. Coccomyces pinicola and S. massonianae present similar characteristics of ascomata and ascospores, thus Coccomyces pinicola is transferred to Stipamyces here. For a detailed description of this species see Lei et al. (2013).

Therrya pini (Alb. & Schwein.) Höhn., Ber. dt. bot. Ges. 35: 422. 1917.

Ascomata scattered to clustered, circular to slightly irregular, sessile, dark brown to black, opening by irregular splits. Covering stroma formed by dark brown (#2b180b) to black (#000000), thick-walled angular cells. Epithecium present or absent. Basal Covering stroma poorly or well developed, consisting of carbonized, thick-walled, angular cells. Internal matrix of Covering stroma well developed, formed by thin-walled, irregular cells or hyaline hyphae, filled or not filled with crystals. Subhymenium consisting of textura intricata or hyaline cells. Paraphyses filiform, not branched, tips swollen or not swollen. Asci ripening sequentially, clavate, thin-walled, J–, 8-spored or 4-spored. Ascospores aseptate to septate, filiform or fusiform, hyaline, covered or not covered by a gelatinous sheath.

Conidiomata scattered or gregarious, lenticular, 300–500 μm in diam, dark brown to black, ostiole absent, opening by irregular tears in thecovering layer. In vertical section, conidiomata subepidermal, upper layer and basal layer 20–60 μm thick, consisting of pale to dark brown textura angularis, with thin- to thick-walled cells. Conidiogenous cells smooth, cylindrical to ampuliform, discrete, holoblastic, sympodial to synchronous, 9–11.5(–13) × 2–2.5 μm. Conidia aseptate, hyaline, smooth, cylindrical, straight to curved, with rounded apices, 8–12(–22) × 1–1.5(–2) μm (Description based on Reid and Cain 1960; McMullin et al. 2019).

Reid and Cain (1960) reviewed the taxonomic history of the genus Therrya, listing numerous synonyms under three species names: Coccomyces strobi, Therrya fuckelii (Rehm) Kujala, and Therrya pini. Korf (1973) accepted this treatment and emphasize fusiform, multiseptate ascospores lacking gelatinous sheaths as key diagnostic features. Sherwood (1980) further delineated the genus by highlighting its substrate specificity—epiphytic on coniferous substrates—and the epithecium of inflated paraphyses cemented in a brown gel. According to Index Fungorum (https://www.indexfungorum.org) records, there are currently seven legitimate names for the genus Therrya, which are Th. abieticola C.L. Hou & M. Piepenbr., Th. eucalypti Z.Q. Yuan, Th. fuckelii, Th. piceae A. Funk, Th. pini, Th. pseudotsugae, and Th. tsugae A. Funk. Based on Hou and Piepenbring (2007), Th. eucalypti Z.Q. Yuan might be closely related to Colpoma Wallr. instead of Therrya based on its morphology and host. Therrya abieticola, originally placed within this genus, has been transferred to the genus Neotherrya in the present study. Molecular data are available for only two species, Th. fuckelii and Th. pini. Phylogenetic analysis reveals a distinct clade comprising Co. guizhouensis, Co. strobi, Parvacoccum pini, Th. fuckelii, and Th. pini (Clade 4, Fig. 1), exhibiting morphological similarities with other members of the genus. Based on phylogenetic inference and morphological affinities, it is proposed to transfer Co. strobi, Co. guizhouensis, and Pa. pini into the genus Therrya.

CHINA, Guizhou Province, Zhijin, alt. ca. 1700 m, on twigs of Pinus armandii Franch. (Pinaceae), 2 May 1979, B.F. Hu 16393 (ACAFP 66501, holotype).

Lin et al. (1994) described Coccomyces guizhouensis on twigs of Pinus armandii in the genus Coccomyces. In our phylogenetic tree, sequences of C. guizhouensis form a sister clade to Therrya pinicola (synonym Parvacoccum pini) and Therrya strobi (synonym Coccomyces strobi). Therrya pinicola differs from C. guizhouensis by having a dark zone below the subhymenium and ascospores with more obtuse ends. Coccomyces strobi differs from C. guizhouensis by having asci with slightly pointed apices and ascospores that are filiform-clavate with rounded apex. Although the ascospores of Co. guizhouensis are not septate, they are fusiform in shape and the apex of paraphyses are sometimes enlarged and form an epithecium. Based on the phylogenetic position and morphological characters, C. guizhouensis is transferred to the genus Therrya here.

Parvacoccum pini R.S. Hunt & A. Funk, Mycotaxon 33: 52. 1988. To avoid a homonym with Therrya pini (Alb. & Schwein.) Höhn.

CANADA, B.C., Mesachie Lake, on branches of Pinus monticola Douglas ex D.Don (Pinaceae) killed by blister rust, 20 Jun. 1986, R.S. Hunt, DAVFP 23420 (holotype).

Hunt and Funk (1988) described Parvacoccum pini on branches of Pinus monticola in the genus Parvacoccum R.S. Hunt & A. Funk. In the phylogenetic tree, the molecular sequences of Th. strobi form a sister clade to Parvacoccum pini. Parvacoccum pini differs from Th. strobi by having a dark zone below the subhymenium and asci with obtuse apices. Hunt and Funk (1988) established the genus Parvacoccum based on the symmetrically fusiform shape of the ascospores with funnel-shaped appendages, separating it from the genus Coccomyces. However, the fusiform ascospores and the apically expanded paraphyses suggest that the species be placed in Therrya. Given that a species named Therrya pini (Alb. & Schwein.) Höhn. already exists within the genus Therrya, the Therrya pini (R.S. Hunt & A. Funk) L. Zhuo & C.L. Hou would be a later homonym of the former. In accordance with the International Code of Nomenclature for algae, fungi, and plants, we avoid a nomenclatural conflict by selecting “pinicola” as the new epithet for the species previously known as Parvacoccum pini.

Therrya pinicola differs from Therrya pini by distinct molecular sequence data and morphologically by short, aseptate ascospores.

This is the first record of Therrya pinicola for China and on the new host Pinus pumila (Pall.) Regel.

CHINA, Heilongjiang Province, Yichun, Xing’anling Arboretum, 47.7474°N, 128.8899°E, alt. ca. 300 m, on twigs of Pinus pumila (Pinaceae), 16 Jun. 2024, C.L. Hou, L. Zhuo, and Y. Gao, HOU 2237 (BJTC 2024097); 47.7474°N, 128.8899°E, alt. ca. 300 m, on twigs of Pi. pumila, 16 Jun. 2024, C.L. Hou, L. Zhuo, and Y. Gao, HOU 2238B (BJTC 2024098).

Figure 32. 

Therrya pinicola (HOU 2237/BJTC 2024097) a ascomata on a twig of Pinus pumila b, c mature ascomata. Scale bars: 1 mm (a); 500 μm (b); 1 mm (c).

Figure 33. 

Therrya pinicola on Pinus pumila (HOU 2237 /BJTC 2024097) a part of an ascoma in vertical section b paraphyses, mature asci with ascospores, and immature ascus c liberated ascospores. Scale bars: 100 μm (a); 10 μm (b); 5 μm (c).

CANADA, Ontario, Simcoe County, Midhurst, on Pinus strobus L. (Pinaceae), 4 Jun. 1951, R.F. Cain, TRTC 23,578 (holotype).

Reid and Cain (1961) described Co. strobi on branches of Pinus strobus in the genus Coccomyces. In the phylogenetic tree, Co. strobi is closely related to Therrya species; ITS rDNA sequences similarities with other Therrya species range from 91.86%–97.62%. In the phylogenetic analyses, sequences from seven isolates of Co. strobi formed two clades. Among them, isolates NB-645C, NB-641A, DAOMC251937, DAOMC251589, and DAOMC251575 were submitted by Tanney J.B. in McMullin et al. (2018). Their study provides detailed information on isolation sources, and morphological illustrations, which agree with the typical description of Co. strobi, and establishes the correspondence between morphology and phylogeny. Therefore, the sequences from these isolates form a clade representing Co. strobi. In contrast, the sequence from isolate AFTOL-ID 1250 formed a separate branch, suggesting that it may represent a different species. Further examination of the material is needed to confirm its taxonomic status. The tips of the paraphyses of Co. strobi are curled, coiled, tending to form an epithecium, therefore, according to the morphological characters and phylogenetic relationship, Co. strobi belongs to the genus Therrya.

Tryblidiopsis pinastri (Pers.) P. Karst., Bidr. Känn. Finl. Nat. Folk 19: 262. 1871.

Ascomata scattered to clustered, circular, stalked, black, opening by irregular splits. Covering stroma formed by dark brown (#2b180b) to black (#000000), thick-walled angular cells. Basal Covering stroma usually absent. Internal matrix of Covering stroma well developed, formed by hyaline, branched, septate hyphae embedded in gelatinous matrix, filled or not filled with crystals. Subhymenium consisting of textura intricata. Paraphyses filiform, branched or not branched, with slightly swollen tips. Asci ripening sequentially, cylindrical to clavate, thin-walled, J–, 8-spored or 4-spored. Ascospores 0–6 septate, filiform, fusiform to clavate, hyaline, covered by a gelatinous sheath (Description based on Livsey and Minter 1994).

Livsey and Minter (1994) reviewed the generic concept, and considered Tryblidiopsis to be a monotypic genus. Tryblidiopsis magnesii Tanney & Seifert, Try. sichuanensis S. Wang, P.F. Cannon & C.L. Hou, and Try. sinensis S. Wang, P.F. Cannon & C.L. Hou have been described subsequently (Wang et al. 2014b; Tanney and Seifert 2019). These species all have stalked ascomata, grow on Picea spp., and have ascospores that are fusiform to clavate, septate, with a thick gelatinous sheath. In the present study, three new species are added to this genus based on morphological analyses, host substratum, and phylogenetic data (Clade 2, Fig. 1).

Referring to the name of the location (Changbaishan) where the type specimen was collected.

This new species is similar to Tryblidiopsis sinensis, but differs by having a brown covering stroma, curved ascospores, and tips of paraphyses strongly swollen to 3–5 µm.

CHINA, Jilin Province, Yanbian Chaoxianzu Autonomous Prefecture, Antu County, Changbaishan, 42.0867°N, 128.0745°E, alt. ca. 1600 m, on twigs of Picea jezoensis var. komarovii (V. N. Vassil.) W. C. Cheng & L. K. Fu (Pinaceae), 14 Jun. 2024, C.L. Hou, L. Zhuo, and Y. Gao, HOU 2210 (BJTC 2024070, holotype).

Ascomata on twigs, erumpent from bark, scattered, not associated with pale areas. In surface view, ascomata round to elliptical, 1000–1450 × 800–1250 µm, as seen from the side 600–800 µm high, brown (#48240a) to dark brown (#2b180b), opening by irregular splits to expose a yellow (#ffe562) hymenium. Lips absent. In median vertical section, covering stroma 40–60 μm thick near center of ascomata, consisting of an outer layer of carbonized, angular to globose cells and an inner layer of hyaline, angular to globose cells. Basal Covering stroma 5–7 µm thick, located between the subhymenium and the internal matrix of the Covering stroma, consisting of brown to dark brown globose cells. Internal matrix of Covering stroma well-developed, consisting of hyaline, thin-walled, gelatinous cells and hyaline hyphae, mixed with irregular crystals. Subhymenium 15–20 µm thick, consisting of textura intricata and hyaline, angular to globose cells. Paraphyses aseptate, filiform, not branched, swollen to 3–5 µm at tips, 120–140 × 2 µm. Asci ripening sequentially, clavate, apex obtuse, 110–120 × 15–22 µm, thin-walled, J–, 8-spored. Ascospores aseptate, curved fusiform, 16–25 × 4–5 μm, hyaline, covered by a 3–4 µm thick gelatinous sheath.

Conidiomata and zone lines not seen.

CHINA, Jilin Province, Yanbian Chaoxianzu Autonomous Prefecture, Antu County, Changbaishan, 42.0867°N, 128.0745°E, alt. ca. 1600 m, on twigs of Picea jezoensis var. komarovii (Pinaceae), 14 Jun. 2024, C.L. Hou, L. Zhuo, and Y. Gao, HOU 2211 (BJTC 2024071).

Known only from Jilin Province, China.

Wang et al. (2017) cited the immature specimen of Tryblidiopsis sp. (HOU 662) on Picea jezoensis (Siebold & Zucc.) Carrière collected from Jilin Province, Changbaishan. In the context of the present study, we returned to this original collection site and successfully collected the mature specimens HOU 2210 and HOU 2211. The nrITS similarity between the newly collected specimens and HOU 662 is 98%. Furthermore, phylogenetic analysis shows that the newly collected specimens and specimen HOU 662 cluster together. These results indicate that the newly collected specimens HOU 2210 and HOU 2211 are the same species as specimen HOU 662.

The sequences of Try. changbaishanensis form a sister clade with the sequences of Try. pinastri and Try. sinensis. Tryblidiopsis changbaishanensis differs from Try. pinastri by having aseptate ascospores and tips of paraphyses strongly swollen to 3–5 µm. Tryblidiopsis changbaishanensis differs from Try. sinensis by having curved ascospores and a melanized basal Covering stroma between the subhymenium and the internal matrix of Covering stroma.

Figure 34. 

Tryblidiopsis changbaishanensis (HOU 2210/BJTC 2024070, holotype) a ascomata on a twig of Picea jezoensis var. komarovii b, c mature ascomata. Scale bars: 2 mm (a); 500 μm (b); 1 mm (c).

Figure 35. 

Tryblidiopsis changbaishanensis on Picea jezoensis var. komarovii (HOU 2210 /BJTC 2024070, holotype) a part of an ascoma in vertical section b paraphyses swollen at tips, mature asci with ascospores, and immature ascus c liberated ascospores. Scale bars: 100 μm (a); 10 μm (b, c).

Melano- (Greek), referring to the melanized basal Covering stroma between the subhymenium and the internal matrix of the Covering stroma.

This new species is similar to Tryblidiopsis sichuanensis, but differs by a melanized basal Covering stroma between the subhymenium and an internal matrix of the Covering stroma, and an internal matrix filled with crystals.

CHINA, Yunnan Province, Lijiang, Laojunshan, 26.6452°N, 99.7838°E, alt. ca. 3290 m, on twigs of Picea likiangensis (Franch.) E. Pritz. (Pinaceae), 17 Aug. 2023, C.L. Hou, L. Zhuo, and S.Y. Zhao, HOU 2105 (BJTC 2023235, holotype).

Ascomata on twigs, erumpent from the bark, scattered or aggregated in groups of three to five ascomata, not associated with pale areas. In surface view, ascomata round to elliptical, 1000–1150 × 800–1000 µm, as seen from the side 900–1200 µm high, black (#000000), opening by irregular splits to expose a yellow (#ffe562) hymenium. Lips absent. In median vertical section, covering stroma 50–110 μm thick near the center of ascomata, consisting of an outer layer of carbonized, angular to globose cells and an inner layer of hyaline, angular to globose cells. Basal Covering stroma 15–25 µm thick, located between the subhymenium and the internal matrix of the Covering stroma, consisting of brown to dark brown, globose cells. Internal matrix of the Covering stroma well-developed, consisting of hyaline, thin-walled, gelatinous cells and hyaline hyphae, filled with irregular crystals. Subhymenium 10–20 µm thick, consisting of hyaline, angular to globose cells. Paraphyses aseptate, filiform, not branched, slightly swollen at tips, 135–165 × 1 µm. Asci ripening sequentially, clavate, apex obtuse, 120–150 × 15–18 µm, thin-walled, J–, 8-spored. Ascospores 1-septate, fusiform, 20–25 × 3–4 μm, hyaline, covered by a ca. 2 µm thick gelatinous sheath.

Conidiomata and zone lines not seen.

CHINA, Yunnan Province, Lijiang, Laojunshan, 26.6452°N, 99.7838°E, alt. ca. 3290 m, on twigs of Picea likiangensis (Pinaceae), 26 Jul. 2024, C.L. Hou, L. Zhuo, and X.N. Sui, HOU 2307 (BJTC 2024157).

Known only from Yunnan Province, China.

The multi-locus gene analysis indicates that the sequences of Tryblidiopsis melanostroma form a well-supported clade sister to the sequences of Try. sichuanensis. Tryblidiopsis melanostroma is morphologically similar to Try. sichuanensis, but the latter has an internal matrix of Covering stroma without crystals and lacks a melanized basal Covering stroma between the subhymenium and the internal matrix of the Covering stroma. Interestingly, a similar melanization phenomenon has been observed in Try. magnesii, where the inner wall of the covering stroma is melanized (Magnes 1997; Tanney and Seifert 2019). The taxonomic relevance of this feature remains uncertain and requires further study. Therefore, Try. melanostroma is considered to be a distinct species.

Figure 36. 

Tryblidiopsis melanostroma (HOU 2105/BJTC 2023235, holotype) a ascomata on a twig of Picea likiangensis b, c mature ascomata. Scale bars: 2 mm (a); 1 mm (b); 500 μm (c).

Figure 37. 

Tryblidiopsis melanostroma on Picea likiangensis (HOU 2105/BJTC 2023235, holotype) a part of an ascoma in vertical section, having a melanized basal Covering stroma between the subhymenium and an internal matrix of the Covering stroma b paraphyses, mature asci with ascospores, and immature ascus c liberated ascospores. Scale bars: 100 μm (a); 15 μm (b); 10 μm (c).

Referring to ascospores with3–6 septae.

This new species is distinguished from other Tryblidiopsis species by its 4-spored asci and 3–6-septate ascospores.

CHINA, Yunnan Province, Lijiang, Laojunshan, 26.6452°N, 99.7838°E, alt. ca. 3290 m, on twigs of Picea likiangensis (Pinaceae), 17 Aug. 2023, C.L. Hou, L. Zhuo, and S.Y. Zhao, HOU 2107 (BJTC 2023238, holotype).

Ascomata on twigs, erumpent from the bark, scattered, not associated with pale areas. In surface view, ascomata subround to elliptical, 1500–2200 × 1100–1400 µm, as seen from the side 600–800 µm high, black (#000000), opening by irregular splits to expose a dark gray (#373737) hymenium. Lips absent. In median vertical section, covering stroma 35–60 μm thick near the center of ascomata, consisting of an outer layer of carbonized, angular to globose cells and an inner layer of hyaline, angular to globose cells. Basal Covering stroma absent. Internal matrix of the Covering stroma well-developed, consisting of hyaline hyphae, filled with irregular crystals. Subhymenium 25–35 µm thick, consisting of hyaline, angular to globose cells. Paraphyses aseptate, filiform, not branched, slightly swollen at tips, 160–185 × 1 µm, covered by a ca. 1 µm thick gelatinous sheath. Asci ripening sequentially, clavate, apex obtuse, 120–150 × 18–25 µm, thin-walled, J–, 4-spored, no aborted ascospores were observed. Ascospores 3–6-septate, rod-shape, tapering to narrow base, 40–50 × 4–6 μm, hyaline, covered by a 2–3 µm thick gelatinous sheath.

Conidiomata and zone lines not seen.

CHINA, Yunnan Province, Lijiang, Laojunshan, 26.6452°N, 99.7838°E, alt. ca. 3290 m, on twigs of Picea likiangensis (Pinaceae), 17 Aug. 2023, C.L. Hou, L. Zhuo, and S.Y. Zhao, HOU 2104 (BJTC 2023234); 26.6619°N, 99.7758°E, alt. ca. 3280 m, on twigs of Pi. likiangensis, 20 Jun. 2021, C.L. Hou, M.J. Guo, and H. Zhou, HOU 1750 (BJTC 2021061).

Known only from Yunnan Province, China.

The phylogenetic analysis shows that sequences of this new species form a separate clade and cluster with sequences of Try. changbaishanensis, Try. magnesii, Try. melanostroma, Try. pinastri, Try. sichuanensis, and Try. sinensis. Morphologically, Try. multiseptata can be distinguished from other Tryblidiopsis species by its 4-spored asci and 3–6-septate ascospores.

Figure 38. 

Tryblidiopsis multiseptata (HOU 2107/BJTC 2023238, holotype) a ascomata on a twig of Picea likiangensis b, c mature ascomata. Scale bars: 2 mm (a); 1 mm (b); 500 μm (c).

Figure 39. 

Tryblidiopsis multiseptata on Picea likiangensis (HOU 2107/BJTC 2023238, holotype) a part of an ascoma in vertical section b paraphyses, mature asci with ascospores, and immature ascus c liberated ascospores. Scale bars: 100 μm (a); 10 μm (b, c).

Referring to the name of the province (Yunnan) where the specimen was collected.

This new species is distinguished from other Tryblidiopsis species by its filiform ascospores each with 1–3-septa, and occurrence on a non-Picea host.

CHINA, Yunnan Province, Lijiang, Laojunshan, alt. ca. 3200 m, on twigs of Tsuga chinensis (Franch.) Pritz. (Pinaceae), 11 Jul. 2007, C.L. Hou, HOU 487 (BJTC 201203, holotype).

Ascomata on twigs, erumpent from the bark, scattered, not associated with pale areas. In surface view, ascomata round to irregular, 800–1100 µm, as seen from the side 350–550 µm high, black (#000000), opening by irregular splits to expose a pale yellow hymenium. Lips absent. In median vertical section, covering stroma 70–100 μm thick near the center of ascomata, consisting of an outer layer of carbonized, angular to globose cells, and an inner layer of hyaline, angular to globose cells. Basal Covering stroma absent. Internal matrix of Covering stroma well-developed, consisting of hyaline hyphae and angular to globose cells. Subhymenium 20–40 µm thick, consisting of textura intricata and hyaline, angular to globose cells. Paraphyses aseptate, filiform, not branched, curved, sightly swollen at tips, 110–160 × 2–2.5 µm, covered by a thin gelatinous sheath. Asci ripening sequentially, clavate, apex obtuse, 90–135 × 11–18 µm, thin-walled, J–, 8-spored. Ascospores 1–3-septate, filiform, tapering at both ends, 45–90 × 2–4 μm, hyaline, covered by a thin gelatinous sheath.

Conidiomata and zone lines not seen.

CHINA, Yunnan Province, Lijiang, Xinzhu village, alt. ca. 2400 m, on twigs of Tsuga chinensis (Pinaceae), 20 Jul. 2013, C.L. Hou, HOU 1116B (BJTC 2013047).

Known only from Yunnan Province, China.

Wang et al. (2017) indicated that Tryblidiopsis species are host-specific and grow only on Picea spp., but the new species Try. yunnanensis grows on Tsuga chinensis. Four species of Rhytismataceae are known from Tsuga spp, namely Coccomyces heterophyllae A. Funk, Coccomyces mertensianae Sherwood, Discocainia treleasei (Sacc.) J. Reid & A. Funk, and Therrya tsugae. However, for none of them molecular sequence data are available. Morphologically, Co. heterophyllae, Co. mertensianae, and D. treleasei differ from Try. yunnanensis by aseptate ascospores, and Th. tsugae differs from Try. yunnanensis by ascomata opening by a single longitudinal split. Usually, Tryblidiopsis spp. have fusiform to clavate ascospores and more or less stalked ascomata, whereas Try. yunnanensis has filiform ascospores and sessile ascomata. Sequence similarities of ITS rDNA between Try. yunnanensis and other sequences of Tryblidiopsis species are 86.63%–92.61%, and nrLSU rDNA are 91.16%–97.72%. Based on the differences of ascomata, ascospores, host and sequence similarities, it seems that a new genus should be erected to accommodate this species. To avoid establishing too many genera, however, we tentatively assign this species to Tryblidiopsis.

Figure 40. 

Tryblidiopsis yunnanensis (HOU 487/BJTC 201203, holotype) a ascomata on a twig of Tsuga chinensis b, c mature ascomata. Scale bars: 1 mm (a); 500 μm (b, c).

Figure 41. 

Tryblidiopsis yunnanensis on Tsuga chinensis (HOU 487/BJTC 201203, holotype) a part of an ascoma in vertical section b paraphyses, mature asci with ascospores, and immature ascus c liberated ascospores. Scale bars: 100 μm (a); 15 μm (b); 20 μm (c).

CHINA, Sichuan Province, Xiaojin County, Jiajinshan, on twigs of Picea sp. (Pinaceae), 25 Jul. 2006, C.L. Hou, HOU 288 (BJTC 2006015).

In the multigene phylogenetic analysis, the sequence of the specimen HOU 288 forms a distinct clade closely related to the sequence of Try. melanostroma and Try. sichuanensis. The ITS rDNA sequence similarity of this specimens and these two species is 97%. Because the specimen is immature, it is labelled as Tryblidiopsis sp. 1.

Figure 42. 

Tryblidiopsis sp. 1 (HOU 288/BJTC 2023053) a immature ascomata on a twig of Picea sp. b, c immature ascomata. Scale bars: 2 mm (a); 500 μm (b); 1 mm (c).

CHINA, Heilongjiang, Mudanjiang, Jingpohu National Scenic Area, on twigs of Picea sp. (Pinaceae), 5 Aug. 2011, C.L. Hou, HOU 956 (BJTC 2011114).

In the multigene phylogenetic analysis, the sequence of this specimen clusters with the sequences of Try. changbaishanensis. The ITS rDNA sequence similarity of HOU 956 and Try. changbaishanensis is 97%. Unfortunately, no mature ascomata of this specimen have been obtained, so specimen HOU 956 is labelled as Tryblidiopsis sp. 2.

Figure 43. 

Tryblidiopsis sp. 2 (HOU 956/BJTC 2011114) a ascomata on a twig of Picea sp. b, c immature ascomata. Scale bars: 1 mm (a); 500 μm (b); 200 μm (c).