Cresponea ancistrosporelloides Sparrius & Sipman
Mycobank MB 517759
Thallus crustose, saxicolous, over 10 cm wide, flat, pale grey, finely areolate, up to 150 µm thick; areoles irregular in size and outline, 0.1–0.6 mm wide, separated by thin and irregularly winding fissures; cortical layer up to 30 µm, of dense, winding hyphae; medulla ca. 100 µm, white, with loose hyphae and ca. 8 µm diam., thick-walled trentepohlioid photobiont cells. Apothecia frequent, black, slightly glossy, 0.3–0.6 mm in diam., with flat disc and thin margin not extending above the disc. Excipulum dark-brown, strongly conglutinated and without individual hyphae visible. Hypothecium pale. Hymenium 60–65 µm tall, clear, I+ reddish throughout; paraphysoids 2 µm thick, septate, hardly branched between the asci, apically swollen to ca. 4 µm and furcate; terminal cell or two uppermost cells clavate, 3–4 x 6–10 µm, covered by a brown layer with tiny granules. Epithecium dark-brown, ca. 20 µm, composed of densely agglutinated paraphyse tips. Asci pyriform, ca. 50–60 x 20–22 µm. Ascospores 8/ascus, (6–)8-loculate, fusiform, with thin walls and septa without thickened edges, at base usually attenuated into a ca. 20 µm long tail which is spiralled in the ascus, (30–)45–50 x 5 µm. Pycnidia not seen. Secondary chemistry: thallus K–, C–, KC–, UV–; no substances found.
The genus Cresponea was monographed by Egea & Torrente (1993). Since then only few additional species were recognized, C. apiculata Egea et al. (Egea et al., 1996) and C. litoralis Elix (Elix, 2007). C. ancistrosporelloides differs markedly from all known species by the long basal tails of the spores. Only in C. apiculata are basally attenuated spores reported, but the attenuated part is short and the spores are 11–14-loculate. The attenuated spores may be an overlooked feature because they were recently described from several taxa: Ancistrosporella australiensis (G. Thor) G. Thor (Thor, 1990 as Ancistrospora), Opegrapha curvata Aptroot [Aptroot et al. 1997; = Ancistrosporella curvata (Aptroot) Komposch)] and Ancistrosporella psoromica Komposch, Aptroot & Hafellner (Komposch et al., 2002). These species differ in their lirelloid ascomata and partly byssoid thallus. Also in these species, the asci are much longer than the spores, so that the spore tails are probably not spiralled below the main body of the spores in the asci, as in C. ancistrosporelloides. Therefore the new species is provisionally placed in Cresponea rather than in Ancistrosporella. However, the genus Cresponea seems to be not completely fitting since the ascospores lack the thick walls and thickened septum edges illustrated by Egea & Torrente (1993).
The epithet reflects the tailed spores which resemble those of the genus Ancistrosporella.
Known so far only from the type collection, from volcanic rock at 740 m in sclerophyll scrub in West Australia.
Type:—AUSTRALIA: Western Australia: Trail to Toolbrunup Peak, Stirling Ranges, Stirling Range National Park, 40 km SW of Borden; 118°3’E, 34°23’S, 740 m; dry sclerophyll forest with pockets of denser shrub vegetation, on volcanic rocks; Sep 1994, Elix 41495 (holotype B; isotype CANB).
Additional specimens examined (paratypes):—None.
Cresponea saxicola apotheciis parvis 0.3-0.6 mm diametro, ascosporis (6-)8-locularibus basaliter frequenter uncinatis et torsivis, 35–50 x 5 µm.