Revision and description of six species of Choeradoplana (Platyhelminthes, Tricladida), with an emendation to the genus

Abstract

Living representatives of the Neotropical genus Choeradoplana Graff, 1896 (Geoplaninae, Tricladida, Platyhelminthes) are easily recognized by the typical shape of the head which is laterally expanded, rolled-up, and ventrally provided with two glandular cushions. In this study, the morphology and phylogeny (cytochrome C oxidase subunit I gene) of several species of land planarians are taxonomically investigated. Four of the six species studied are new to science, namely: Ch. eudoxiae Silva & Carbayo, sp. nov., Ch. claudioi Lago-Barcia & Carbayo, sp. nov., Ch. onae Lago-Barcia & Carbayo, sp. nov., and Ch. riutortae Lago-Barcia & Carbayo, sp. nov. The species Choeradoplana albonigra and Ch. eudoxiae deviate from the usual body shape pattern in that the head does not present lateral expansions nor glandular cushions, becoming indistinguishable from its sister genus Cephaloflexa. Pseudogeoplana tristriata (Schultze & Müller, 1857) is also redescribed from a newly collected specimen and was discovered to be a member of Choeradoplana. Graff (1899) also studied another specimen that was considered to be conspecific with P. tristriata; however, in this new it is concluded that it is not conspecific but rather a new species. The name Pseudogeoplana aevipandemiae Lago-Barcia & Carbayo, sp. nov. is suggested for Graff’s specimen.