Geoplana piratininga is a species of land planarian belonging to the subfamily Geoplaninae.[1] It is found in areas within the Atlantic Forest in the municipalities of São Paulo and Mongaguá, Brazil.
Geoplana piratininga is a flatworm around 25 mm in length and 4 mm in width. The body is relatively short and has parallel margins; the front tip is rounded and the back tip is pointed. The dorsal side has a traffic-red band running down the middle, bounded on each side by a black stripe; the stripe is bordered by a white stripe, which is in turn bordered by a black band, which is then bordered by a thin marginal white line. The ventral side is a whitish color.[2]
Aside from its coloration, it is distinguished from other members of Geoplana by having the dorsal and ventral insertions of the penis papilla at the same transverse plane, non-folded walls of the female atrium, and a female-to-male atrium length ratio of 2.
The specific epithet, piratininga, is derived from the historical Tupi language name of the type locality of São Paulo, Piratininga plains.