Flora of New Zealand Series

Type : Topeliopsis muscicola Kantvilas & Vězda [Topeliopsis muscigena (Stizenb.) Kalb.]

Description : Thallus crustose, sometimes evanescent. Photobiont green, trentepohlioid. Ascomata apothecia, sessile or subimmersed, subglobose to barrel-shaped, perithecioid, or sometimes becoming gyalectoid, closed at first, later opening by a terminal pore. Exciple cupular, colourless or brown, externally with a thin, thalline layer, internally with hyaline periphyses. Disc strongly and persistently urceolate. Hamathecium of paraphyses, straight, simple, apices not swollen. Asci I−, cylindrical, thin-walled, apex markedly thickened when young, 1–8 spored. Ascospores colourless to pale-greyish, ellipsoidal or oblong, thin-walled at first, thick-walled at maturity, halonate, with transverse septa, submuriform or densely muriform, turning reddish or purple in I. Conidiomata unknown. With or without secondary chemistry.

Topeliopsis is a rather heterogeneous genus included in the family Thelotremataceae (Eriksson et al. 2004; Pennycook & Galloway 2004; Eriksson 2005), for taxa with sessile, exfoliating, perithecioid apothecia, with a cupular, usually brown-pigmented exciple, very well-developed periphyses, a persistently and deeply urceolate disc, markedly apically thickened asci (when young) and very large, thin-walled, colourless ascospores turning reddish or purple in KI. When the genus was first described two species were known (Kantvilas & Vězda 2000) to which Kalb (2001a) added a further three species from Australia and emended the generitype T. muscicola Kantvilas & Vězda Kantvilas & Vězda, to T. muscigena (Stizenb.) Kalb. Two species were subsequently described, from North America and Brazil (Breuss 2000a; Aptroot 2002e). In the most recent treatment of the genus (Frisch & Kalb 2006) a further three species are described, and two taxa formerly in Thelotrema are added to Topeliopsis, which now comprises nine species. Three of these are known from New Zealand. It is also possible that Thelotrema novae-zelandiae (q.v.) belongs here.