Trichoura pardeos, Londt, Jason G. H. & Dikow, Torsten, 2016

Londt, Jason G. H. & Dikow, Torsten, 2016, A review of the genus Trichoura Londt, 1994 with the description of a new species from the Northern Cape Province of South Africa and a key to world Willistonininae (Diptera, Asilidae), African Invertebrates 57 (2), pp. 119-135 : 120-125

Trichoura pardeos sp. n. Figs 10-12, 15-19

Etymology.

Gr. Pardos m. - leopard + oros, -eos n. mountain. Named after the type locality of Tierberg Nature Reserve (Tierberg meaning tiger (= leopard) mountain).

Description.

Based on all available NMSA material.

Head: Dark red-brown to black, but colour masked by strong silver and gold pruinescence, white and pale yellow-white setose. Antennal scape and pedicel brown-orange, postpedicel and terminal style dark red-brown, fine silver pruinose, scape and pedicel yellow-white, short setose, style tipped with almost transparent spine-like sensory element. Segmental ratios (scape (as 1): pedicel: postpedicel: style (segment + sensory element) - 1: 1.4: 3.8: 1.2 (0.8 + 0.3). Face dark red-brown to black, but colour masked by strong silver pruinescence, profile plane except for slight epistomal gibbosity. Mystax shiny white, moderately well-developed, confined to small epistomal gibbosity, setae closely arranged forming a dorsoventrally compressed shield covering proboscis. Face narrow, parallel-sided, width of face: width of head (at widest point) ratio - 1: 8.2: 2.2. Frons and vertex somewhat divergent, width of face to width of vertex (at level of anterior ocellus) ratio - 1: 2.2, dark red-brown to black, but colour masked by strong silver (frons) and weak gold pruinescence (vertex). 1 pair of frontal setae. Ocellar tubercle projecting only slightly above vertex, with 2 pairs of small ocellar setae. Postocular (occipital) region dark red-brown to black, but colour masked by strong silver pruinescence. Occiput with short, pale yellow-white macrosetae dorsally, short white macrosetae laterally and many fine, shiny white setae ventrally. Palpi dark red-brown, small, 2-segmented, fine pale yellow setose. Proboscis straight, tubular, dark red-brown to black, weakly fine white setose.

Thorax: Dark red-brown to black, but colour masked by silver and silver-gold pruinescence, pale yellow and fine white setose. Pronotum dark red-brown, silver pruinose, white setose. Mesonotum dark red-brown to black, entirely silver to silver-gold pruinose, fine white setose except for moderately well developed, pale yellow-white lateral macrosetae (2 npl, 1 spal, 2 pal). Scutellum dark red-brown, entirely silver pruinose, asetose except for 1 pair apical macrosetae. Pleura dark red-brown to black, but entirely strongly silver pruinose, almost asetose except for c. 5 white katatergal macrosetae. Anepisternal setae absent. Anatergites uniformly strongly gold pruinose, asetose.

Legs: Coxae red-brown, strongly silver pruinose, white setose; metathoracic coxae with small bulbous protuberance on anterior surface. Femora red-brown with orange distal and proximal ends, white setose. Tibiae and tarsi orange, terminal parts red-brown, white setose. Claws black with brown-orange basal parts, shorter than terminal tarsomere, gently curved. Empodium orange, straight, slightly shorter than claws. Pulvilli pale yellow, longer than empodium. Wings (Fig. 19) length measured from humeral crossvein to tip, breadth at widest level: Holotype 1.3 × 0.4 mm, paratypes - male (1) 1.4 × 0.5 mm, females (2) both 1.7 × 0.6 mm. Venation: C extends around wing margin terminating at junction of CuA+CuP, although it appears to extend weakly around at least part of cell cup. Alula reduced to a small lobe. All peripheral cells open except for m3 and cua which are closed and stalked. Little variation is evident. Veins mostly dark red-brown except proximally where veins are yellowish, membrane unstained, transparent, much of surface, especially distally, microtrichose.

Abdomen: Entirely dark red-brown, moderately fine gold-silver pruinose, short white setose (T1 with longer setae laterally and along entire posterior margin). ♂ tergites and sternites entirely pruinose, including epandrium which is covered with long shiny white setae. Fused gonocoxites and other visible parts of genitalia shiny apruinose. ♀ with segments 1-6 entirely pruinose, segments 7-9 shiny apruinose. ♂ terminalia (Figs 15-17): Epandrium completely divided medially into two epandrial lobes that closely abut at about 1/3 of their length (Fig. 16); distal tips of lobes broadly truncate terminally (dorsal and lateral views). Proctiger short, projecting distally for a short distance beyond epandrial lobes. Hypandrium wanting, or entirely fused with gonocoxite to form a large component of the terminalia. Fused gonocoxite with a broadly rounded mediodistal lobe best appreciated in ventral view (Fig. 17). Gonostyli dorsoventrally compressed, extending well beyond level achieved by gonocoxites and epandrium. Aedeagus largely hidden amongst other structures, robust, broad in lateral view with distal bifurcated tip. ♀ terminalia (Fig. 18): Ovipositor tubular, approximately as long as deep in lateral view; acanthophorite plates each bearing 5 stout, articulated ‘spines’; three equally large spermathecae, reservoirs tubular (not distinguishable from spermathecal ducts) and unsclerotized; genital fork (furca, S9) divided into two lateral sclerites, without any furcal apodeme.

Holotype.

SOUTH AFRICA: ♂ holotype, 'South Africa: N Cape / Tierberg Nature Reserve / 28°43.012'S, 020°59.805'E / 850m J Londt & T Dikow / 5.ii.2004, sparsely / vegetated exposed hillside’ (NMSA).

Paratypes.

3♂ 3♀, same data as holotype (NMSA); 1♂ 1♀, same data (USNMENT01288302-USNMENT01288303, USNM).

Distribution, phenology and biology.

Known only from the type locality. Collected in February (Table 1). Little is known of the biology. Tierberg Nature Reserve is a small conservation area comprised almost entirely of a large rocky hill on the outskirts of Keimoes, a small town located on the north banks of the Gariep (= Orange) River which provides water for agricultural activities in what is otherwise an arid area of the country. Vegetation is sparse and dominated by succulents such as aloes (Figs 13-14). The flies were found resting on hard-baked ground and stones.