Primary thallus forming cushion made up of large persistent squamules with rounded and incised ends which can reach 5 mm in length, sometimes powdered with mealy soredia. Short and stocky podetions of about 5-7 mm in height, formed by a short stipe bearing a regular cup with the margin sometimes torn with "tapered serrations"; the cup is the same height as the stipe (but there are many variations, sometimes on the same thallus), cortex corticated and finely sorediate and with a mealy appearance. Apothecia rare on the edge of the cup, brown. Photobiont: trebouxioid.
4 known chemotypes:
Chem I: C-, K+ yellow, KC-, P+ red, UV-; atranorin, fumarprotocetraric acid. The most common chemotype.
Chem II: C-, K-, KC-, P+red, UV-; bourgeanic acid, fumarprotocetraric acid. Rare. Chem III: C-, K+ yellow, KC-, P+ red, UV-; atranorin, fumarprotocetraric acid, bourgeanic acid. Rare.
Chem IV: C-, K-, KC-, P+ red, UV-; fumarprotocetraric acid. Rare.
Pioneer species growing on the packed sand of paths or car parks in the dunes, the sandy soil of the moors, the freshly disturbed earth of the sandy gardens along the sea. A species with maritime affinities in our prospecting area, easy to confuse if we do not not the K test with Cladonia grayi and with a miniature of Cladonia chlorophaea grp.
N.B. This taxon is very variable and still incompletely known, we can find numerous forms of podetions on the same thallus see: Cladonia humilis Cf. forma.
N.B. Cladonia conista which is K-, is a very close species formerly synonymized, but it is currently considered as a "semicryptic" species, not macroscopically differentiable, this species is more continental than Cladonia humilis which is relatively Atlantic in Europe and most often K+ yellow.
