Laphyctis gigantella (Loew, 1852)

Londt, Jason G. H. & Dikow, Torsten, 2018, A review of the assassin-fly genus Laphyctis Loew, 1858 with descriptions of two new species (Diptera, Asilidae, Laphriinae), African Invertebrates 59 (1), pp. 75-106 : 80

Laphyctis gigantella (Loew, 1852) Figs 19, 25, 38, 42-45, 56

Stichopogon gigantella Loew, 1852: 658; 1862: 5.

Laphyctis gigantella : Loew 1858: 338; 1860: 88 (160) (Figs 42a wing, 42b antenna).

Laphystia gigantella : Lindner, 1973: 85 (see under argenteofasciata ); Oldroyd, 1974: 103 (fig. 95 ♂ abdomen) (see under argenteofasciata ); 1980: 352 (catalogue).

Redescription.

Based on all available material and photographs of holotype. General appearance as in Fig. 38.

Head: Dark red-brown to black, but colour masked by strong silver-gold pruinescence, shiny white and yellow to pale orange setose. Antennae orange to dark red-brown, fine silver pruinose, especially scape. Scape orange, strongly pale yellow setose ventrally. Pedicel orange, asetose except for a few tiny setae distally. Postpedicel proximally orange, distally dark red-brown, with short broad terminal 2-segemented style with oblique terminal opening enclosing a spine-like sensory element. Segmental length ratios = 1: 0.8: 2.9: 0.8. Face dark red-brown to black, but colour masked by strong gold-silver pruinescence. Width of one eye: face ratio = 1: 0.94 (face slightly narrower than width of 1 eye). Face projecting ventrally, epistomal margin medially smoothly rounded, facial profile slightly convex (Fig. 19). Mystacal macrosetae shiny pale yellow to pale orange, confined to ventral quarter of face. Dorsal region of face fine white setose. Frons and vertex dark red-brown to black, colour masked by shiny gold-silver pruinescence, fine white setose. Ocellar tubercle fine white setose (no macrosetae). Postocular (occipital) region dark red-brown to black, colour masked by strong silver pruinescence. Occiput with rows of c. 7 short, pale yellow macrosetae dorsally and many fine, shiny white setae, mostly ventrally. Palpi dark red-brown, 2-segmented, fine white setose. Proboscis straight, shiny dark red-brown, fine white setose proximally and distally.

Thorax: Dark red-brown to black with some orange-brown parts, uniformly strongly silver-gold pruinose, pale yellow and fine white setose. Pronotum red-brown, silver pruinose, fine white setose. Mesonotum red-brown, entirely silver-gold pruinose, uniformly fine shiny yellow-white microsetose except for moderately developed, yellow lateral macrosetae (1 npl, 3-4 spal), pal setae absent. Scutellum red-brown, entirely fine gold-silver pruinose. Discal scutellar setae fine orange, apical scutellar setae absent. Pleura red-brown to dark red-brown, entirely silvery pruinose, fine white setose. Katatergal macrosetae poorly developed, fine white. Anatergites uniformly strongly silver pruinose, asetose. Postmetacoxal area membranous. Legs: Fairly uniform red-brown, proximal ends of femora and tibiae somewhat orange-brown, shiny white to pale yellow setose. Coxae strongly silver pruinose. Claws well-developed, black with brown-orange basal parts. Empodium brown, straight, as long as pulvilli. Pulvilli pale yellow, well-developed. Wings (Fig. 25): ♂ (2) 9.3 × 3.2 mm, ♀ (5) 10.2 × 3.8 mm (females slightly larger than males). Venation: All marginal cells open except for m3 and cua, which are closed and stalked. Veins orange-brown to dark brown, membrane unstained, transparent, microtrichose (except for small sections of some basal cells). Cell cup with weak bordering vein (C) and microsetae. Alula well-developed, lacking bordering vein and microsetae.

Abdomen: Dark red-brown to black, fine white and yellow microsetose, macrosetae short yellow-white, silver pruinose. Tergites (T1-6 well-developed and clearly evident, others reduced and hidden from view below T6) dark red-brown to black, anteriorly yellow microsetose, fine gold-silver pruinose, posteriorly white microsetose, silver pruinose. T1-6 with pale yellow-white medial macrosetae. Sternites red-brown, fine white setose, dull gold pruinose.

Male terminalia (Figs 42-44): Genital bulb rotated clockwise through approximately 180°. T7-8 and S7-8 reduced and poorly defined. Epandrium large, almost twice as long as broad, bilobed in distal quarter, tips of lobes broadly rounded (Fig. 42). Proctiger short, deep, not projecting beyond distal epandrial lobes. Hypandrium poorly defined, posterior margins weakly sclerotized, difficult to appreciate, especially in lateral view, subtriangular in ventral view (Fig. 44), wider than long. Gonocoxites moderately well-developed, approximately twice as long as deep, and sharply pointed distally in lateral view, long, densely arranged macrosetae on distal margin of gonocoxite. Gonostyli subdivided at base into two fairly slender, and fairly straight lobes, ventral lobe possessing a short pointed branch just beyond midlength. Phallus with a slender basal region tipped with a moderately large, terminal, three pronged head.

Female terminalia (Fig. 45): Relatively broad and dorsoventrally flattened. Segments 1-6 well-developed, segments 7-8 reduced. Subgenital plate moderately well-developed, broader than long, with undulating, distal margin featuring four distal lobes.

Type material.

Holotype. Mozambique: Inhambane: 1♀ holotype 'Inhambo / Peters’ [blue], ' Laphyctis / gigantella ', ’10369’, ’Type’ [red], 'Coll. / H. Loew’ (ZMHB).

Type locality: Loew (1852, 1858, 1862) repeatedly gives the country of origin as Mozambique. In 1858 and 1860 he cites Inhambane as the locality of the holotype although that name does not appear on the specimen. It must therefore be concluded that ’Inhambo’ is an abbreviation for Inhambane [c. 23°53'17"S, 35°23'46"E 12m].

Material examined.

Malawi: Central: 1♀ 'Nyasaland. / Domira Bay [c. 13°33'09"S, 34°24'26"E 476m] / 167 ft 17.1.16, 123c [sideways] / Dr. W. A. Lamborn’, 'Pres. by / Imp. Bur. Ent.', ’1919-314’, ’NMHUK010624224’ (BMNH); 1♀ 'Nyasaland. / Domira Bay / 167 ft 12.1.16 / Dr. W. A. Lamborn’, ’1916-259’, ’NMHUK010624225’ (BMNH); 1♀ 'Nyasaland. / Chunzi [?] / Nr. Domira Bay / 2420 ft 22.xii.1914 / Dr. W. A. Lamborn’, 'Pres. by / Imp. Bur. Ent. / Brit. Mus. / 1925-122', ’NMHUK010624226’ (BMNH). South Africa: KwaZulu-Natal: 1♂ 'Umfuli R. [? Umfolozi River c. 28°27'23"S, 32°08'48"E 26m] / Natal / Nov. 1895 / G.A.K. Marshall / 1903-17', ’NHMUK010624221’ (BMNH). Zimbabwe: Matebeland North: 1♀ 'Sawmills [c. 19°35'00"S, 28°02'23"E 1065m] / S. Rhodesia / 26.12.1919 / Rhodesia / Museum’, 'S. Rhodesia: / Pres. By / J. Isgaer Roberts. / B.M. 1928-262', 'No type status / det. J. E. Chainey, 1984', ’NHMUK010624216’ (BMNH); 1♂ ' Laphystia / gigantella Loew’, 'Pres. by / Imp. Bur. Ent. / Brit. Mus. / 1923-233', 'Sawmills / S. Rhodesia / 25.12.1919 / Rhodesia / Museum’, ’NHMUK010624228’ (BMNH); 1♀ 'Pres. by / Imp. Bur. Ent. / Brit. Mus. / 1923-233', 'Sawmills / S. Rhodesia / 26.12.1919. / Rhodesia / Museum’, 'No type status / det. J. E. Chainey, 1984', ’NHMUK010624223’ (BMNH); 1♀ 'N. E. Rhodesia / Buyamuryama [? poorly handwritten] / Boma / 19-xii-1910 / E. O. Silverlock. / 1911-168' ’NHMUK010624211’ (BMNH).

Lindner (1973: 85) lists three females of L. gigantella from Gobabeb, Namibia, which we identified as L. eremia sp. n. (see above).

Distribution, biodiversity hotspots, phenology and biology.

Fairly widely distributed in the southern parts of Africa being recorded with certainty from Malawi, Mozambique, South Africa and Zimbabwe (Fig. 56). A rarely collected species over a restricted period of time with the most recent collecting event dating to 1919 (Table 1). Two localities overlap with the Maputaland-Pondoland-Albany (in KwaZulu-Na tal, South Africa) and Coastal Forests of Eastern Africa (in Inhambane, Mozambique) biodiversity hotspots, but this species is not endemic to any particular biodiversity hotspot. Adults are clearly summer active, being collected in November, December and January (Table 2). Although specimens lack habitat information the species probably inhabits sandy areas such as lake shores, river banks and similar situations.