Psoroglaena is characterised by its
crustose (crust-like) or minutely filamentous
thallus (the main body of the lichen). The cells (outer protective layer) often feature small (tiny nipple-like projections). The (the
photosynthetic partner in the lichen
symbiosis) is
Auxenochlorella, a
green alga belonging to the class
Trebouxiophyceae. The reproductive structures in this genus are
perithecia (flask-shaped fruiting bodies with an opening at the top), which are typically pale brown, though rarely dark brown. The surface of these perithecia is generally smooth, but occasionally may display projecting
hyphae (fungal filaments) or a distinctive ring-shaped collar. The (a protective covering over the perithecium) is absent in this genus. The (the outer wall of the fruiting body) is usually pale, though it may rarely contain some brown pigmentation. When viewed in cross-section, the cells of the exciple are periclinally elongate (stretched parallel to the surface), sometimes with a surface layer of isodiametric (equal in all dimensions) cells. The (the sterile tissue within the fruiting body) consists of (short filaments lining the ostiole or opening), while interascal filaments are absent. The gel within this tissue turns red when treated with
iodine (I+ red). The
asci (spore-producing cells) contain between one and eight spores, are -cylindrical (club-shaped to cylindrical) in form, and show thickening at the apex when young. They do not react with iodine (I-) or
potassium iodide (K/I-). The (spores produced in asci) are transversely
septate (divided by cross-walls) to (divided by both longitudinal and transverse walls),
ellipsoidal in shape, smooth, lack a (outer spore coating), and are colourless.
Conidiomata (asexual reproductive structures) have not been observed in this genus. Chemical analysis reveals no detectable
lichen substances. ==Species==