The form of the paranota in Barydesmus nangaritza sp. nov. is unique among the American Platyrhacidae. Checking all descriptions and published figures, only Barydesmus exsul (Cook, 1896a) leaves some doubt about its possible similarity to the paranota of B. nangaritza sp. nov., as in the original description it is said: "lateral carinae usually deeply excised opposite to the pore" (Cook 1896a: 54). We have examined hotographs of the type specimen of B. exsul and the form of the paranota is highly variable among segments. Only paranota 5 and 12 appear clearly excised opposite to the pore (even if not as deeply as in B. nangaritza sp. nov.), but most paranota of B. exsul have 3–4 blunt teeth providing the rough, irregular external margins typical of several other species of the family. Gonopod structure among Barydesmus species, as in other Platyrhacidae, is highly homogeneous and peripheral characters should be considered as major diagnostic features in this group (Hoffman et al. 2011; Martínez-Torres 2016). Given the available information, it is not feasible to postulate solid hypotheses regarding the affinities among species of Barydesmus without a full review of the genus.
Recuero, E.; Sánchez-Vialas, A. (2018). A new distinctive species of Barydesmus (Diplopoda, Polydesmida, Platyrhacidae) from Ecuador, with an annotated bibliographical checklist of the American Platyrhacidae. <em>Zootaxa.</em> 4482(2): 245.available online athttps://doi.org/10.11646/zootaxa.4482.2.2 Available for editors