Trypetheliopsis yoshimurae

Trypetheliopsis yoshimurae has a thin, crustose thallus that lies on the surface of the substrate rather than sinking into it. The thallus is continuous rather than broken into patches, greenish grey to greyish green, somewhat glossy and smooth, with a distinct outer cortex. The sexual fruiting bodies are grouped into slightly to strongly raised, wart-like perithecial swellings 0.7–1.5 mm across that spread at the base. Their tops are dark purplish brown with a paler, slightly sunken centre where one to several pore-like ostioles open to the outside.^[2]

Inside the perithecia, the hymenium is densely filled with oil droplets, and the hamathecium consists of branched, interconnected filaments. The asci are club-shaped, 120–130 × about 50 μm, with markedly thickened upper walls and a clearly defined ocular chamber. Each ascus contains 5–8 ascospores that are ellipsoid, slightly curved and divided by a single cross wall. The spores measure 55–74 × 17–22 μm, with the two cells slightly swollen and sometimes a little constricted or thickened at the septum; the spore walls are evenly 2–3 μm thick and lack a separate outer perispore.^[2]

Asexual reproduction takes place in specialised campylidia-like pycnidia. These structures have a collar-like extension that is blackish to dark purplish grey-brown, entire or dissected at the tips, and open on the side facing away from gravity. They are 0.4–0.7 mm high in total, consist of a single internal cavity packed with conidia, and are lined by a 15–25 μm thick layer of conidiophores. The conidia are single-celled, ellipsoid to ovoid, and measure 5–6.5 (rarely up to 10) × about 3 μm.^[2]

Trypetheliopsis yoshimurae is known from warm-temperate regions of Japan on the Pacific side of the mainland, originally reported from Shizuoka, Kōchi, Miyazaki and Kagoshima Prefectures.^[2] A later survey of the lichen funga of Chiba Prefecture recorded the species as new to that prefecture, extending its known range northwards and making Chiba the northern limit of its distribution. The lichen grows on the bark of evergreen and deciduous broad-leaved trees and occasionally on rock; the Chiba material was collected on the trunk of Quercus acuta in low-montane forest near a ridge on a steep Pacific-facing slope in southern Chiba.^[2][3]