A new species of Planipapillus (Onychophora: Peripatopsidae) that defies the original concept of its genus

Planipapillus Reid, 1996 (Onychophora: Peripatopsidae) is a genus of peripatus or velvet worms from south-eastern Australia, consisting of 12 nominal species, unique in having a patch of reduced papillae on the heads of males. Specimens from Mt Useful, Victoria, that lack this trait were identified as a species of Planipapillus on the basis of morphological and molecular analyses in 1999 and 2001, respectively. That species is herein described as P. absonus sp. nov., and an emended diagnosis for the genus is provided to accommodate this unusual addition. The relationship between modified head papillae and mating is discussed.