Slideshow image
Sphaerellothecium propinquellum (Nyl.) Cl. Roux & Triebel (redirected from: Stigmidium congestum)
Family: Mycosphaerellaceae
[Pharcidia congesta Körb.,  more]
Sphaerellothecium propinquellum image
Vegetative hyphae: brown to dark brown, very distinct, torulose, with short smooth-walled cells, 4-6(-7) µm in diam., strongly BCr+ blue violet Pseudothecia: black, sessile to semi-immersed, globose to oblong, 50-90 x 4574 µm wall: entirely medium to dark brown, mostly 8-16 µm thick, hyphae 3-9 µm wide and 3-9 µm long hamathecium: paraphysoids: short, 3-6 x 1.2 µm periphyses: 6-12.5 x 2-3(-3.5) µm asci: bitunicate, sessile, broadly cylindrical to clavate, 36-69 x 11-17 µm, 8-spored; epiplasma: BCr+ pale violet, with an ocular chamber ascospores: hyaline but becoming light brown when mature, 1-septate, lower cell a little longer then the upper one, constricted at the septa, ellipsoid, oblong to subclavate, often with oil droplets, (10-)11.5-15(-16) x (3-)4-5.5(-6) µm, with rounded apices, 1-2-seriate inside of the ascus; epispore: smooth, thin-walled, BCr+ violet; inner perispore: becoming finely verrucose and outer perispore forming a thin halo, BCr- or BCr+ blue Pycnidia: subglobose, 45-35 µm in diam.; wall: entirely brown conidiogenous cells: 4-6 x 3-4 µm conidia: 3-4.5 x 0.5-1 µm. Hosts: the apothecial disc and thalline margin (sometimes also on the thallus) of Lecanora carpinea agg. and L. subcarpinea World distribution: Europe and North America (U.S.A.) Sonoran distribution: known from one collection in Arizona.