Species groups of Sisyphini in southern Africa

In southern Africa, five species-groups are proposed for the genus Sisyphus according to their morphological affinities. Due to the limited amount of sexual dimorphism in Sisyphus; characterization largely applies equally to males and females.

(1) S. muricatus group: Seven southern African species, comprising: S. muricatus; S. neobornemisszanus; S. fasciculatus; S. perissinottoi; S. manni; S. swazi sp. n and S. alveatus . The external morphology (Figs. 2 A–G) and the genitalia (Figs. 3 A–G) differ among the members of the group.

(2) S. goryi group: Five species, comprising: S. bicuariensis sp. n; S. caffer; S. genierorum; S. goryi and S. sordidus . Although external morphological differences are subtle (Figs. 5 A–E), the shapes of parameres are relatively different between species (Figs. 6 A–E).

(3) S. umbraphilus group: Comprises a single southern African species, S. umbraphilus (Fig. 8A); genitalia (Fig. 9A)

(4) S. costatus group: Five species, comprising: S. impressipennis; S. costatus; S. gazanus; S. inconspicuus sp. n; and. S. australis sp. n (Figs. 11 A–E). The shape of the parameres differs between species (Figs. 12 A–E).

(5) S. seminulum group: Four southern African species: S. splendidus; S. oralensis S. nanniscus; and S. auricomus sp. n (Figs. 14 A–D). The genitalia of S. splendidus were not studied because no male specimens were available. The parameres of other species members of the group are clearly different (Figs. 15 A–C).

In Neosisyphus, identification is complicated by sexually dimorphic characters that vary in morphology with body size. Females are often difficult to separate into species. Species-groups defined for Neosisyphus follow Montreuil (2015b). In southern Africa five species-groups have been recorded.

(1) N. barbarossa group: Four species: N. barbarossa; N. calcaratus; N. tembyi sp. n and N. setiger (Figs. 17 A–D). Morphological differences are clear in major males, but, less so in minor males and females. However, species members are easily separable through the differences between the phallobase and shapes of the parameres (Figs. 18 A–D).

(2) N. spinipes group: Three species: N. fortuitus; N. infuscatus and N. spinipes (Figs. 20 A–C). All species bear distinctly different parameres (Figs. 20 A–C). Although there are clear differences between major males, in the latter two species, there are often close morphological similarities.

(3) N. tibialis group: One southern African species: N. mirabilis (Fig. 23A). The species shows distinctive spinose sculpturing of the legs. The aedeagus is shown in Fig. 24A.

(4) N. quadricollis group: Two southern African species: N. quadricollis and N. kuehni (Figs. 26 A–B). Both species show differences in the phallobase and the shape of parameres (Figs. 27 A–B).

(5) N. rubrus group: Composed of two similar southern African species: N. macrorubrus and N. rubrus (Figs. 29 A–B). Parameres differ in shape between the species (Figs. 30 A–B).