Cratera steffeni is a species of land planarian belonging to the subfamily Geoplaninae.

The dorsal base color is a pale yellow, which can be seen on the margins.

[2] Aside from its coloration and shape, it is distinguished from other members of Cratera by having dorsal eyes restricted to lateral bands, a conspicuous glandular margin with four types of secretory cells, a bell-shaped pharynx, a short esophagus, the anteriormost testes being posterior to the ovaries, sperm ducts that open laterally into the proximal portion of the prostatic vesicle, an extrabulbar, unpaired prostatic vesicle with a tubular distal portion and an ample proximal portion, ovovitelline ducts that emerge dorsolaterally from the back half of the ovaries and ascend laterally to the female atrium, a short common ovovitelline duct, a long, dorso-anteriorly curved vagina, equal atria lengths, and a lack of folds separating the male and female atria.

[2] The specific epithet, steffeni, was given in honor of naturalist MSc.

Clemente José Steffen S.J., for his "relevant contribution to the ethnobotany in southern Brazil".