Peripatopsidae
Peripatopsidae or the Southern Velvet Worms are one of two extant families of velvet worm. This family includes more than 140 described species distributed among 41 genera, but some authorities deem only 131 of these species to be valid. The French zoologist Eugène Louis Bouvier proposed this family in 1905 with Peripatopsis as the type genus.
Description
The Peripatopsidae exhibit relatively many characteristics that are perceived as original or "primitive" with respect to the Peripatidae. The species in this family have relatively few legs, ranging from 13 pairs to a maximum of 29 pairs. Behind or between the last leg pair is the genital opening. This family includes both oviparous genera and viviparous genera, which adopt various modes of supplying nourishment to their embryos, ranging from lecithotrophic ovoviviparity to matrotrophic viviparity. The Peripatopsidae lack a placenta, however, which has been found in velvet worms only in the neotropical Peripatidae.
Most genera in this family have only 15 pairs of legs; one genus has 15 or fewer, and another genus includes only species with fewer than 15. Two genera are characterized by 16 pairs of legs, another genus has 15 or 16, and only four genera include velvet worms with more than 16: Opisthopatus, Peripatopsis, Metaperipatus, and Paraperipatus. Although leg number is fixed within most peripatopsid species, the four genera that feature more than 16 leg pairs exhibit some variation in leg number within species as well as among species. Peripatopsid species with more legs also feature greater intraspecific variation in leg number.
Distribution
The distribution of the Peripatopsidae is circumaustral; in particular, they inhabit Australasia, South Africa and Chile. Most genera in this family are found in Australia, one genus is found in New Zealand, and another is found in both; two genera are found in South Africa, two others are found in Chile, and one other is found in Indonesia and New Guinea.
Phylogeny
Peripatopsidae is divided into two main clades: one with members in South Africa and Chile, and another with members in Australasia. The majority of species belong to the Australasian clade, with most occurring in Australia. Below is a genus-level phylogeny of Peripatopsid velvet worms. This phylogenetic tree does not include all genera.
Genera
The family contains the following genera:Acanthokara Reid (malacologist)|Reid], 1996Aethrikos Reid, 1996Aktinothele Reid, 1996Anoplokaros Reid, 1996Austroperipatus Baehr, 1977Baeothele Reid, 1996Centrorumis Reid, 1996Cephalofovea Ruhberg et al., 1988Critolaus Reid, 1996Dactylothele Reid, 1996Diemenipatus Oliveira, Ruhberg, Rowell & Mayer, 2018Dystactotylos Reid, 1996Euperipatoides Ruhberg, 1985Florelliceps Tait & Norman, 2001Hylonomoipos Reid, 1996Konothele Reid, 1996Kumbadjena Reid, 2002Lathropatus Reid, 2000Leucopatus Leuropezos Reid, 1996Mantonipatus Ruhberg, 1985Metaperipatus Clark, 1913Minyplanetes Reid, 1996Nodocapitus Reid, 1996Occiperipatoides Ruhberg, 1985Ooperipatellus Ruhberg, 1985Ooperipatus Dendy, 1900Opisthopatus Purcell, 1899Paraperipatus Ruhberg, 1985Paropisthopatus Ruhberg, 1985Peripatoides Pocock, 1894Peripatopsis Pocock, 1894Phallocephale Reid, 1996Planipapillus Reid, 1996Regimitra Reid, 1996Ruhbergia Reid, 1996Sphenoparme Reid, 1996Tasmanipatus Ruhberg et al. 1991Tetrameraden Reid, 1996Vescerro Reid, 1996Wambalana Reid, 1996