Sturnidoecus australafricanus Gustafsson & Bush, new species

(Figs 399–405)

Type host. Corvinella melanoleuca expressa Clancey, 1961 — magpie shrike. Type locality. Nwamayiwane, South Africa.

Diagnosis. Only known species in its species-group, and easily separated from most other Sturnidoecus by the structure of male genitalia. The overall shape of the mesosome of St. australafricanus n. sp. (Fig. 384) is similar to that of the St. basilewskyi (Fig. 385), St. pastoris (Fig. 390) and St. sturni (Fig. 396) species-groups, being generally fairly rounded, with paired hooks on distal margin. However, the lateral margins of the mesosome are more sinuous in St. australafricanus than in members of the other three species groups. Also, unlike the St. basilewskyi and St. sturni species groups, there are hook-shaped structures on each side of the ventral surface of the mesosome in St. australafricanus . The proximal mesosome of St. australafricanus is widely trapezoidal, with a convex anterior margin, as in the St. basilewskyi species-group, whereas in the St. sturni species group the proximal mesosome is smaller with a concave anterior margin; the proximal mesosome of the St. pastoris species-group is irregular, but still widens at the anterior margin. In all four groups the ames and pmes form a more or less obvious pair of distantly converging rows, but only in the St. australafricanus group are the ames and pmes both of roughly equal size.

Unlike most other groups of Sturnidoecus, St. australafricanus (Figs 399–400) have reduced sternal plates that are narrower than the subgenital plate in both sexes. Uniquely in Sturnidoecus, female St. australafricanus (Fig. 400) have sternal plates only on segments III–VI, but not on segment II. The female genitalia are typical for the genus, and the lack of this sternal plate may be the best character to differentiate female St. australafricanus from other species.

Description. Both sexes. Head shape, structure, and chaetotaxy as in genus description and Fig. 401; as1 present. Dorsal preantennal suture extends only slightly towards preantennal nodi. Coni broad and short compared to other Sturnidoecus spp., barely or not reaching distal margin of scapes. Preocular nodi comparatively large, rectangular. Postocular nodi comparatively large, rounded; pos located just posterior to nodi. Gular plate slender, spade-shaped. Thoracic and abdominal segments as in genus description and Figs 399–400. Posterior margin of pterothorax rounded in both sexes. Sternal plates small in both sexes.

Male. Distal abdomen of male distorted in single available male, and not illustrated. Sternal plates present on segments II–VI, small (Fig. 399). Abdominal chaetotaxy as in Table 11 and Fig. 399. Male genitalia as in genus and species group description and Fig. 402–404. Measurements ex Corvinella melanoleuca expressa (n = 1): TL = 1.45; HL = 0.46; HW = 0.47; PRW = 0.30; PTW = 0.43; AW = 0.57.

Female. Sternal plates present on segments IV–VI (Fig. 400). Abdominal chaetotaxy as in Table 11 and Fig. 400. Subgenital plate roughly triangular, narrowing considerably distally (Fig. 405). Vulval margin (Fig. 405) gently rounded, with 5–7 long, slender vms on each side, and 10–13 short, thorn-like vss on each side; 7–10 short, slender vos on each side; distal 1–2 vos median to vss. Measurements ex Corvinella melanoleuca expressa (n = 6): TL = 1.63–1.77; HL = 0.48–0.52; HW = 0.49–0.53; PRW = 0.30–0.32; PTW = 0.44–0.47; AW = 0.61–0.71.

Etymology. The species epithet refers to the predominantly southern African distribution of the host.

Type material. Ex Corvinella melanoleuca ex pressa [as Corvinella melanoleuca]: Holotype ♂, Nwamayiwane, South Africa, 24 Apr. 1983, Braack & Espie, PHTH-22 (NHML). Paratypes: 6♀, same data as holotype (NHML).