Neotherrya pinicola Lan Zhuo & C. L. Hou, 2025

Zhuo, Lan, Wang, Hai-Qi, Zhang, Peng, Sui, Xiao-Nan, Guo, Mei-Jun, Wang, Shi-Juan & Hou, Cheng-Lin, 2025, New genera and species of coniferous twig-inhabiting Rhytismatales from China, IMA Fungus 16, pp. e 138790-e 138790 : e138790-

Neotherrya pinicola Lan Zhuo & C. L. Hou sp. nov.

Figs 26 , 27

Etymology.

Referring to the host genus Pinus .

Diagnosis.

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

Type.

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) .

Sexual morph.

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 (# 2 b 180 b), 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.

Asexual morph.

Conidiomata and zone lines not seen.

Distribution.

Known only from Yunnan Province, China.

Notes.

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.

Figures

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).