Open Access

Mosadoluwa Adetola Badejo, Steffen Woas, Ludwig Beck

• This paper is the first of a series in which more information will be added to the existing on biogeographical distribution of oribatid mites. Here we describe a new species of a phthiracarid mite collected from forest floor litter in southwestern Nigeria. Differences between this species, Atropacarus (Hoplophorella) nigeriensis, and other Hoplophorella species are the foveoli on the aspis and notogaster, the shape of notogastric setae, as well as shapes and chaetotaxy of the genital and anal plates. More differences in taxonomically important features such as the morphological features of the infracapitulum and epimeron as well as leg chaetotaxy between this species and others could not be determined, not only because of lack of information on the latter in literature, but also because many type specimens are not available for dissection which must be done in order to reveal fine morphological details. Atropacarus (Hoplophorella) nigeriensis belongs to the "cucullata" group of Hoplophorella which possess one enlarged adanal seta. It differs from other members of this group in respect of adanoanal and tarsal chaetotaxy. Hoplophorella is considered as a subgenus of Atropacarus in this paper, because there is no evidence in literature that Hoplophorella as a group is a separate phylogenetic entity.