Pyrenomycetes Species Page

Xenolophium guianense

Large separate ascomata
Huhndorf, Mycologia 85(3): 495 (1993)

Pleosporomycetidae, Incertae sedis
Figure from EF2852
Complete Description
Ascomata globose, 400-600 _m diameter, 400-625 _m high, clustered, erumpent superficial, papillate; surface roughened; no subiculum. Wall of textura angularis in surface view; in longitudinal section uniformly 25-50 _m thick, irregularly pigmented, two-layered, with external heavily-melanized crust, inner layer of elongate, flattened, compressed, hyaline to light brown, irregularly pigmented, thickened cells, individual cell boundaries obscured in both layers. Papilla short cylindrical to bluntly conical, longitudinally compressed, 175-300 _m long, 100-300 _m wide, 100-175 _m high; wall composed of small, heavily melanized cells; ostiole slit-like, 30-40 _m wide, with periphyses. Pseudoparaphyses 1.0-1.5 _m wide, numerous, trabeculate, with abundant lattice-like anastomoses, with gelatinous coating. Asci elongate clavate, 115-125 x 9-10 _m, long-stalked (stalk 70-80 _m long), numerous, basal and lateral completely lining the peripheral wall of the centrum, thin-walled, dehiscence unknown; apex rounded, apical chamber present, without ring, not fluorescent; with eight ascospores, biseriate above, uniseriate below. Ascospores fusiform, 22-25(27) x (3.5)4-4.5 _m, hyaline, smooth, without sheath or appendages, one-(three) septate, slightly to not constricted at the septum.