Afromelittodes mimos, Londt, 2003

Londt, Jason G. H., 2003, A revision of the afrotropical genus Afromelittodes Oldroyd & Van Bruggen, 1963 (Diptera: Asilidae: Laphriinae) and discussion of its possible mimetic resemblance to bees of the genus Megachile, African Invertebrates 44 (2), pp. 133-146 : 137-141

Afromelittodes mimos sp. n.

(Plate 1 B–C, Figs 1–5 , 17–21 , 22–29 , 30 )

Etymology: Gr. mimos = actor. Refers to the mimicry displayed by this species.

Description: Based primarily on the completely intact holotype, in excellent condition. Descriptions of male and female genitalia are based on dissected paratypes.All features as in solis except as described below.

Head ( Fig. 1 ): Antenna with postpedicel uniform dull silver pruinose; basal element of stylus slightly longer than broad ( Fig. 3 ). Face with mystacal setae entirely white, except for some black ones ventrolaterally; area below antennal sockets shiny and almost completely asetose. Frons and anterior parts of vertex white setose (some black ones adjacent to eye margins). Occipital area almost entirely black setose (a few white ones adjacent to eyes); lower occipital setae shortish, those adjacent to eyes mostly whitish, those behind these black. Palpus ( Fig. 2 ) with basal segment covered with both black and pale yellow setae, terminal segment entirely covered with black setae. Proboscis with basal parts covered with white setae.

Thorax: Mesonotum with surface almost entirely black setose except for a group of white setae situated anteriorly between postpronotal lobes. Scutellum covered with fine black setae. Pleura covered almost entirely with black setae (a few white ones may be mixed in amongst black). Legs: Femora and tibiae with setae predominantly black (those posterodorsally on femora mostly white). Metathoracic tarsi (and tips of tibiae) have bright orange setae ventrally. Wing ( Fig. 4 ): Length (humeral cross-vein to tip) – 11.2 mm, greatest breadth – 5.0 mm (similar to solis , but wings flatter). Membrane entirely transparent. Vein R 4 without ‘spur vein’ basally.

Abdomen: Tergites 1–5 covered mainly with black setae (few shiny whitish ones laterally on T2–4), T6–7 with shiny bright orange setae (a few black ones interspersed). Sternites covered mainly by short black setae (tufts of longish white setae present laterally on S4–6, those on S7 orange); S3 with medial process situated on posterior margin and with tiny black setae only ( Fig. 5 ).

Male terminalia ( Figs 17–25 ) (Windhoek paratype illustrated): Epandrium (T9) slightly tapered distally in dorsal view. Proctiger similar to solis , but lateral cercuslike lobe of dorsal lamellae not jutting out quite as prominently. Gonocoxites fused basally as in solis , but remnants of hypandrium not clearly discerned. Outer lobe of gonocoxite with acute apex of different form to solis , medial lobe somewhat longer, gently undulating in shape and with a small terminal process. Gonostylus down-turned, narrowly sickle-shaped and with somewhat pointed distal end. Aedeagus similar to solis , but central lobe of sheath not projecting hood-like over prongs.

Female terminalia ( Figs 26–29 ) (Okahandja paratype illustrated): S8 bilobed anteromedially, a group of well-developed black setae situated anteriorly on each lobe. Proctiger with poorly discernible, lateral, setose dorsal lamellae; ventral lamellae with large, swollen, setose, lateral lobes. Spermathecae, three in number, all of similar development (central one slightly more darkly coloured). Coiled reservoirs lie one on top of the other almost flush with inner surface of S6. Spermathecae each with three and a half coils, each only slightly thicker than long straight ducts leading to vagina. Straight ducts apparently with a right-angled bend just before they unite near vagina (unfortunately details in this area were not particularly easy to see). Two thin-walled accessory glands, each three times as long as broad, discharge into genital chamber.

Variation: A species showing very little intraspecific variation. Paratypes demonstrate variation in the degree of sclerotisation, the Windhoek ơ being the least sclerotised and possessing orange-brown (scape) or red-brown (legs) coloration instead of the darker conditions seen in the holotype. There is also some variation in pleural setal colour, the Mirabeb ^ has about equal numbers of white and black setae on katatergite and anepisternum. Specimens are remarkably similar in size, paratype wing measurements ranging from 11.7–12.7 mm (length), 5.0– 5.4 mm (breadth).

Material: NAMIBIA: 1ơ paratype, ‘Otjiseva 45 [farm] / Windhoek, S.W.A. / SE 2216BD / 12 Mar. 1971.’, ‘H 1890’ [Collected by C. G. Coetzee & M-L. Penrith] (NMNW); 1^ paratype, ‘Okahandja / S.W.A. 2116DD / 13–14 Mar. 1969 / B. Lamoral + / R. Day’, ‘ Afromelittodes / solis Oldroyd & van Bruggen / det. H. Oldroyd 1972’ [recorded by Oldroyd, 1974] (NMSA); 1^ paratype, ‘South West Africa / Namib/Naukluft Park / Mirabeb 23 27'S / 15 21'E 16.iii.1983 / C.D. Eardley’, ‘Visiting flowers / of Euphorbia sp. ’ (NMSA). SOUTH AFRICA: 1ơ holotype, ‘S Africa: N Cape #16 / 5km W Olifantshoek / 27 57'S: 22 42'E 1350m / Date: 15.iii.1991 / Londt & Whittington / Acacia –Ziziphus veld’, ‘Prey Identification / Ord: Hymenoptera / Fam: Tiphiidae / Anthobosca sp. / Det: D. Brothers’, ‘Prey Catalogue / No. 001476’ (NMSA).

Distribution: Known from the type-locality of Olifantshoek in the Northern Cape Province of South Africa and three localities in central Namibia.

Figures

Figs 1–7. Afromelittodes species. 1–5. A. mimos sp. n. (Olifantshoek holotype). 1. Head, lateral (no setae shown). 2. Palpus (left). 3. Antenna (left lateral, no setae shown). 4. Wing (right). 5. S3, lateral, showing medial setose tubercle.6–7. A. solis Oldroyd & Van Bruggen, 1963.6. S3, lateral, showing medial tubercle near hind margin. 7. Detail of venation showing ‘spur vein’ at base of R4. Scale lines 1 mm (figure numbers given). Abbreviations: S = sternite.

Figs 17–21. Afromelittodes mimos sp. n. Male terminalia (Olifantshoek holotype):17. Lateral.18. Epandrium and proctiger, dorsal. 19. S8, ventral. 20. Genital bulb, ventral. 21. Proctiger, ventral. Scale line 1 mm (for all figures).

Figs 22–29. Afromelittodes mimos sp. n. 22–25. Male terminalia (Olifantshoek holotype): 22–23.Aedeagus. 22.Lateral.23.Ventral.24–25.Gonopodite (left). 24. Lateral.25.Medial.26–29.Female terminalia (Okahandja paratype). 26. S8, ventral. 27–28. Proctiger.27. Dorsal. 28. Ventral. 29. Spermathecae and associated organs, dorsal. Scale line 1 mm (for all figures). Abbreviations: ag = accessory glands, gs = gonostylus, gx = gonocoxite, reservoir.

Fig. 30. Distribution of Afromelittodes species. A. solis (square), A. mimos (triangles). Distribution of savanna biome indicated as shaded region.