The
thallus (lichen body) of
Diploschistes species can be continuous or cracked into small, sections. It varies in colour from grey-white to dark grey or yellowish and can have a smooth to warty () surface, often covered with a powdery coating (). The
medulla, the inner layer of the thallus, reacts with
iodine (I) to turn blue, although this reaction can be variable. The , or
photosynthetic partner, in these lichens is
Trebouxia, a type of
green algae. The
ascomata (fruiting bodies) start off resembling (flask-shaped structures) and later become urn-shaped () and immersed in the thallus. The , or central part, is black and sometimes pruinose. A (a rim of thallus tissue around the apothecia) is present and can either blend in with the thallus or be thick and pruinose. The , a ring of tissue around the apothecia, is fused with the thalline margin and is dark brown to black. It consists of thick-walled, swollen to more or less spherical () cells embedded in a matrix, and extends into pale brown at the upper inside margin. These structures are faintly
septate and not swollen at the tip, often appearing as a fringe on the surface and may close the ascomatal opening under dry conditions. The , the uppermost layer of cells in the apothecia, can be colourless to black and sometimes contains crystalline inclusions. The
hymenium, a spore-bearing layer, is colourless and does not react with iodine (I–). The , the layer below the hymenium, can be colourless to dark brown or black. The , comprising the
paraphyses (sterile filaments among the asci), consists of wavy, mostly unbranched filaments that are sparsely septate and sometimes brown at the tips. The
asci (spore-producing cells) are elongated and club-shaped to somewhat cylindrical, with walls that are evenly thickened at maturity. When young, they have a somewhat abrupt apical thickening with a thin internal apical beak or a downward convex swelling, but lack any apical apparatus. The contents of the asci react with potassium/iodine (K/I) to turn orange-red, while the walls do not react (K/I–). They are not (do not split open at maturity) and contain between one and eight spores. are broadly
ellipsoidal, brown to dark brown or purple-black when mature, and blue-green when immature. They are (having multiple transverse and longitudinal septa), smooth, and lack a distinct outer layer (). They may react with iodine to turn blue (I± blue).
Conidiomata, which produce asexual spores, are in the form of
pycnidia (flask-shaped structures) that appear as slightly raised black warts. The
conidiogenous cells, which produce the
conidia (asexual spores), are either unbranched or branched at the base and are elongated and flask-shaped. The conidia are (rod-shaped) to elongated-ellipsoidal, truncate (flat) to pointed at the base, colourless, and do not have septa.
Diploschistes lichens contain
para-
depsides, such as
lecanoric and
diploschistesic acids, which are
secondary metabolites (
lichen products) that can be identified through chemical tests. ==Species==