A new blunt-hooked pentastomid belonging to the genus Raillietiella Sambon, 1910, from two species of agamid lizards in Namibia

Abstract

The pentastomid Raillietiella namibiensis n. sp., from the lungs of the agamid lizards Agama aculeata aculeata and A. planiceps planiceps taken at Windhoek, Namibia, is described. The type-series comprised 14 mature female and 9 mature males specimens, all with bluntly-rounded tips to the posterior hooks. The flared, rounded base of the male copulatory spicule was furnished with a knobbly extension projecting towards the mid-ventral line, a feature known only in two other species: Raillietiella mabuiae from Mabuya sulcata in Namibia and an as yet unnamed raillietiellid from M. homalocephala from Kenya. Significant differences in annulus number, and in the dimensions of the hooks and copulatory spicules, separate the latter species from R. namibiensis. However, the holotype female of R. mabuiae was immature and therefore of little diagnostic value, whereas the single paratype male possesses an identical spicule to R. namibiensis n. sp., but a larger hook with a much longer barb. The latter difference was sufficiently great (148 vs 108 μm, range 95–115, in R. namibiensis) to justify the recognition of a new species.