Rothus Simon, 1898

Cruz Da Silva, Estevam L. & Sierwald, Petra, 2015, First description of the male of Rothus vittatus Simon, 1898 (Araneae: Pisauridae), with a review of the African nursery web spider genus Rothus Simon, 1898, African Invertebrates 56 (2), pp. 325-342 : 326-327

Genus Rothus Simon, 1898

Rothus Simon, 1898 a: 294 , 298, figs 293–294; Roewer 1955: 197, figs 79–83; Blandin 1977: 546, figs 10–27, 30, 31.

Type species: Rothus purpurissatus Simon, 1898 , by original designation (=junior subjective synonym of R. aethiopicus Pavesi, 1883 ).

Diagnosis: Members of the genus Rothus can be unambiguously distinguished from all other non-pisaurine (sensu Sierwald 1997) African pisaurid genera by the following combination of characters: three cheliceral teeth on the retromargin, AER slightly procurved, PER recurved, wider than AER, and distinct features in the male and female copulatory organs. In males the tegulum is large, with a pronounced anterior projection; the large and pointed conductor; the sickle-shaped embolus, and the median apophysis aligned and pointing almost horizontally retrolaterad.Retrolateral tibial apophysis ( RTA) elongated and with a divided tip. The female copulatory organs feature an anteriorly excavated middle field ( Fig. 8, MF; Blandin 1977: 541, fig. 6) and prominent curved lateral lobes ( Figs 8, 30) with correspondingly widely separated, curved copulatory ducts ( Figs 9, 32).

Relationship: Members of the poorly known genus Chiasmopes Pavesi, 1883 (four species described, males known for a single species only) share similarities with Rothus with regards to the copulatory organs. In males (only known in Chiasmopes lineatus (Pocock, 1898)) the tegulum is equally enlarged, and conductor, embolus, median apophysis, and even the retrolateral tibial apophysis are very similar (Blandin 1977: 541, fig. 5). The female epigynum of the four known Chiasmopes species is very similar to R. vittatus (Blandin 1977: 541, figs 6–9). Only the vulva of Chiasmopes lineatus has been illustrated (Blandin 1977: fig. 29). In this illustration the posterior section of the copulatory ducts are distinctly wider than the more slender ducts in Rothus . In members of the genus Chiasmopes the AER is extremely procurved, with the ALE positioned almost directly beneath the AME ( Blandin 1974: 313, fig. 2), and prosoma and opisthosoma are distinctly longer than wide, whereas in Rothus the habitus is less elongated (Blandin 1977: 541, figs 1–4). Based on features of the copulatory organs, Rothus and Chiasmopes may be congeneric. In the absence of a complete revision of the species of the latter genus and a comprehensive phylogenetic analysis of the Pisauridae , a taxonomic change is premature.

Natural history: Notations on collecting labels from South African specimens of R. aethiopicus indicate that several were found in vegetation and sometimes inside residences.

Distribution: Widely distributed across Africa, from Senegal in West Africa, Ethiopia in East Africa to South Africa ( Fig. 1).