Comatricha clavicolumella B. Zhang & Yu Li, 2016

Bo, Zhang & Yu, Li, 2016, A new species and two new records of Stemonitidaceae from China, Phytotaxa 267 (2), pp. 151-156 : 152

Comatricha clavicolumella B. Zhang & Yu Li , sp. nov.

Mycobank: MB 815624, Fig 1 , 2

Sporocarps in tufts, stalked, 2–2.2 mm total height, purple-brown. Sporocysts 1.3–1.5 mm long, elongate to cylindrical. Stalk 0.7–0.8 mm long, up to 1/3 of the total height, black, shiny. Peridium evanescent. Columella reaching the apex of the sporocysts, usually ending in a clavate expansion at the apex of the sporocysts. Capillitium arising from the entire length of the columella, abundant, dark brown, the threads branched, flexuous, looped at the surface, without free ends. Spores 5–5.5 μm in diam., globose, banded-reticulate with 5–7 meshes across the hemisphere, dark brown.

Holotype:— CHINA. Henan Province: Jigong Mountain Scenic Area, on bark of a dead log, 11 July 2015, Zhang Bo 2015122305 ( HMJAU10522 ).

Etymology:— Clavicolumella (Latin) , referring to columella ending in a clavate expansion at the apex of the sporocysts.

Distribution:— Known only from the type locality, Jigong Mountain Scenic Area.

Comments:— About 42 species of Comatricha have been reported in the world ( Kirk et al. 2008, Lado 2001, 2005 – 15), of which nine species have reticulated spores and 33 species have spines or verruculose spores. Of the accepted species, only C. anomala Rammeloo , C. mirabilis R.K. Benj. & Poitras and C. reticulospora Ing & P.C. Holland are similar to C. clavicolumella in having cylindrical or short cylindrical to ovoid sporocysts and reticulated spores. However, C. anomala has larger sporocarps (1.5–3.3 mm tall) and larger verruculose spores (9–10 μm in diam.), with 2–5 small areas of incompletely reticulated spores ( Rammeloo 1976). Comatricha mirabilis has smaller sporocarps (0.5–1.5 mm tall), a fugacious peridium persisting at the base as a small collar, and larger spores approximately 10–13 μm in diameter (Benhamin & Poitras 1950). Comatricha reticulospora has larger, delicately reticulate spores (c. 8–10 μm in diam.) with about six meshes across the diameter ( Ing & Holland 1968).

Figures

FIGURE 1. Fruiting bodies of Comatricha clavicolumella (holotype). Bars: A = 2 mm, B = 1.5 mm, C, D = 1 mm.

FIGURE 2. Comatricha clavicolumella (holotype):A. Sporocarp. B. Part of columella and capillitia. C, D. Clavate expansion at the apex of columella and part of capillitia by transmitted light. E, F. Spore marked with banded-reticulate with 7 meshes across the hemisphere. Bars: C = 50 μm, D = 10 μm.