Pyrenomycetes Species Page

Hormosperma pusillum

Small separate ascomata
phragmospore
Penz. & Sacc., Malpighia 11: 402. 1897

Sordariomycetidae
Chaetosphaeriales
Figure from SMH1158
Complete Description
Ascomata subglobose to ovoid, not collapsing, dark brown to black, 175-230 µm diam., superficial, occurring scattered or clustered in small groups, setose. Setae scattered over entire ascoma, brown, stiff, apex blunt, pale colored, 40-70 x 3-4 µm. Ascomatal wall in longitudinal section uniformly 14-18 µm thick; composed of polygonal-to-elongate, pale brown, pseudoparenchymatic cells. Ascomal apex short papillate, indistinct. Paraphyses 3-5 µm wide, sparse, septate, tapering toward apex. Asci cylindrical to clavate, short-stalked, 60-70 x 4.5-6 µm, unitunicate, with an indistinct apical ring, with eight biseriately arranged ascospores. Ascospores fusiform, hyaline, smooth, 7-septate, 13-16.5 x 2-3 µm, immediately disarticulating into eight part-spores; part spores globose, pale brown, verrucose 2-3 µm diam.
Occurrence
Found on decaying wood. Our collections are from Puerto Rico. The type was described from Indonesia (Java). Figure from SMH1158 and SMH1846.
Similar Taxa Comments
These collections match the description given by Penzig and Saccardo for a tropical collection from Java. Two additional genera have ascospores that disarticulate easily. Melanopsammella species have ascospores that are less septate and have Chloridium or Gonytrichum anamorphs. Ascochalera gabretae Reblova has ascospores that are 8-12 septate and has a Chalara-like anamorph. Hormosperma pusillum could be related to Ascochalara. The setae have pale apices and look like they might form a Chalara-like anamorph but conidiophores and conidia were not seen on the substrate and attempts at culturing were unsuccessful.
Reference
Réblová, M. 1999. Teleomorph-anamorph connections in Ascomycetes 2. Ascochalara gabretae gen. et sp. nov. and its Chalara-like anamorph. Sydowia 51:210-222.