Anabarhynchus venabrunneis Ferguson & Glatz, 2019

Ferguson, D. J., Glatz, R. V. & Yeates, D. K., 2019, New stiletto flies in the genus Anabarhynchus Macquart (Diptera: Therevidae) from Kangaroo Island, South Australia, Zootaxa 4646 (2), pp. 331-345 : 340-343

Anabarhynchus venabrunneis Ferguson & Glatz sp. nov.

( Figures 8–10 )

http://zoobank.org/NomenclaturalActs/ 151ECA00-B9BA-4057-A05F-4DE763A540FB

Type material. Holotype: Male. AUSTRALIA: South Australia: Kangaroo Island, Boobook Hill Sanctuary ; [35°50.356’S 137°56.839’E]; sweep net; 5 October 2008. R.V. Glatz; ( SAMA _29:004654) ( SAMA).

Paratype: 1 Male, 5 Females AUSTRALIA : South Australia: 1♂ Kangaroo Island (south west), Hanson Bay car park, 25 October 2007; on Acacia nr. retionodes; 36°01.021’S 136° 51.143’E;. D.A. Young; ( SAMA _ 29:004655) ( SAMA) . 1♀ House site at Lot 51 Three Chain Rd. , ~ 6km W D’Estrees Bay, ~ 1km W Elsegood Rd. , SE Kangaroo Is. 31–Oct–2015 R.V. Glatz; 35°54.620’S 137°33.018’E ( RGC _13946)( RGC) . 1♀ House site at Lot 51 Three Chain Rd. , ~ 6km W D’Estrees Bay, ~ 1km W Elsegood Rd. , SE Kangaroo Is. 31–Oct–2015 R.V. Glatz; 35°54.620’S 137°33.018’E; ( RGC _13945)( ANIC _29: 040882) ( ANIC) . Victoria: 1♀ Wahgunyah , 36°00’28.44”S 146° 23’41.39”E; by hand, 14 October 2016; J.G. Lumbers; ( ANIC _29: 040887) ( ANIC) ; 2♀ 10km W. Port Fairy , on coastal vegetation; 29 October 1981; M.G. Jefferies (Collection); (MEI: 109671-72) ( ANIC _29: 040885 -86) ( ANIC) .

Diagnosis. Lower frons slightly bulging, upper frons flat; male frons 5.0 x anterior ocellus width; broadly distributed with erect, black frontal pile longer than antennal scape; occipital macrosetae black admixed with weaker pale setae; scutum brownish grey with indistinct grey vittae; katepisternum and prosternal furrow without pile; wing vein margins infuscate brown and stigma blackish. Femoral setae: fore femur 3–4 pd, 0–1 p v weak; mid-femur 2 pd, 1–4 pv; hind femur 1 av. All femora dark grey with narrow, yellow-brown apical bands.

Description. Body length ( Fig. 8 ): 11 mm. Wing length: 9 mm Head. Frons ( Fig.9 ), upper frons flat, lower frons slightly bulging; frons width 5.0 x the anterior ocellus width; upper frons brownish grey; lower and middle frons blue-grey, area lateral of antenna and along parafacial with pale grey pubescence; area lateral of antenna with broad, grey, velvet mark that contacts eye margin and nearly meets the antennal base; frontal pile erect, black, broadly distributed and longer than scape. Scape and pedicel grey; scape 3x pedicel length; surface of flagellum velvet blackish grey. Occiput convex, grey pubescence and 27–29 black macrosetae on each side. Palpus basal quarter grey, apical three-quarters yellowish with white pile distributed along length; labellum dark grey; prementum with black setae. Thorax. Scutal chaetotaxy black (pairs): np, 4–5; sa, 2; pa, 1; dc, 2; sc, 2. Scutum with a thin brown vitta, between yellowish grey vittae, each laterally margined by intermittent dark grey vittae. Katepisternum and prosternal furrow without pile; pleura grey; coxae grey with long white pile admixed with strong black macrosetae. Wing. Hyaline and slightly opaque, veins dark brown; vein margins narrowly infuscate dark brown; stigma blackish; costal setae beyond humeral cross-vein arranged in 2 rows. Haltere. Dorsal surface of the stem mostly yellow-brown with apical surface dark grey; dorsal surface of knob velvet dark grey. Legs. Femoral setae: fore femur 3–4 pd, 0–1 p v weak; mid-femur 2 pd, 1–4 pv; hind femur 1 av. All femora dark grey with a narrow yellow-brown apical band, fore femur with dark grey along the dorsal surface and on the basal ventral surface; hairs on the hind femora ventral surface variable in length with the longest reaching half the femur width. Tibiae yellow-brown with basal and apical margins darkened. Abdomen. Tergites surfaced with dense grey pubescence; anterior medial margin narrowly darkened, laterally these broaden as oval marks; lateral edge with erect, white pile; sternites covered with dark grey pubescence, sternites 2–7 with sparse, white pile. Terminalia . Paratype ( SAMA _29:004655): epandrium ( Fig. 10A ). 2 x wider than long measured along the mid-line; anterior margin broadly indented; lateral margins converging towards a broadly concaved posterior margin; posterolateral margin ventrally curved; posterior with strong elongate pale setae; sub-epandrial plate fused with the hypoproct along the posterior and lateral margins, and with a ridge along its anterior margin (see Fig. 10A ). Gonocoxite ( Fig. 10B ), anteriorly connected by darkly sclerotised hypandrium and longitudinally by thin membrane; gonocoxite appear onion-shaped when viewed ventrally; posterior surface with elongate, weakly sclerotised setae. Apex of gonocoxal apodeme darkly sclerotised, extending beyond anterior margin. Inner gonocoxal process tapered and curved medially, apex with several robust and darkly sclerotised setae. Gonostylus basally robust, narrowing rapidly, with a group of weak setae on dorsal, inner surface, with apical margin reflexed dorsally. Ventral lobe triangular and short. Aedeagus ( Fig. 10C, D ), distiphallus tapered and curved ventrally; dorsal apodeme of parameral sheath broadly triangular, lateral margins reflexed dorsally; ventral apodeme anteriorly broad and anterolateral corners forming narrow projections beyond anterior margin; lateral ejaculatory apodeme broad, band-like; ejaculatory apodeme with subapical lateral lobes.

Variation. The femoral darkening along the dorsal, and on the basal ventral surfaces may be faint or not present. Male: Body length; 9 mm. Wing length; 8 mm. Frons width 4.6 x anterior ocellus width; occiput macrosetae range 20–32 black on each side; femoral setae: fore femur 2–3 pd, 1 pv weak or hair-like; mid-femur 1 pd, 1 pv; hind 1 av macrosetae.

Female: Body length in female: 10–11 mm. Wing length in female: 8–9 mm. Frons width 5.5 x anterior ocellus width. Occiput yellow-grey with 18–22 black macrosetae on each side. Femoral setae: fore femur 2–3 pd, 0–1 p v weak; mid-femur 1–2 pd, 2 pv; hind femur 1 av. Tergites 2–7 have anterior band reducing in area posteriorly, with broad dark grey posterior margins. Paratype female ( RGC _13946): Sternite 8 ( Fig. 10F ), elongate, with a longitudinal length 1.3 x width; anterior medial margin with ‘funnel-shaped’ indentation; anterior and anterolateral surfaces are darkly sclerotised; medial region weakly sclerotised, with deep depressed area, divided along midline by distinctive ridge; posterior half wide and weakly sclerotised, with a distinctively wide rounded posterior, midline with a narrow ridged connects with the medial depressed area with posterior indention; robust black setae dense arranged along lateral and posterior surfaces of deep depressed area; posterior surface with slightly weaker black setae that extend to posterior margin. Furca ( Fig. 10E ), posterior frame broad, ‘U’-shaped of varied strength, with short, weak internal struts medially; anterior beam anterior margin anteriorly arched, anterolateral frames weak that supports broad ‘ear-like’ lobes; anteroventral lobe short and ‘coat-hanger’ shaped, not extending beyond the lateral frame.

Etymology. The specific epithet ‘ venabrunneis ’ refers to the brown wing veins that differentiate this species from similar species.

Comments. Anabarhynchus venabrunneis is known from two male and two female specimens on KI and taken in October; and recently three additional females have come to our attention that where collected from two Victorian locations, one inland on the Murray River, and two on the coast near Port Fairy. Anabarhynchus venabrunneis is closely related to A. dimidiatus but different in several ways. All the femora are dark grey femora; occipital macrosetae are black admixed with weaker white macrosetae; the black macrosetae, range in number with 20–32 on each side in the male, and 18–28 in the female; wing veins red-brown, their margins infuscate brown, and stigma dark brown; stem of halter apical surface dark grey; frons width in the male is 5.0 x anterior ocellus width and in the female 5.5 x the anterior ocular width. Male epandrium 2 x as wide as long along midline; inner gonocoxal process apical setae are elongated and slender and finely tapering to apices; the ventral apodeme anterolateral corners have dorsally projecting processes, and its anterior margin has a short projecting process medially; female, sternite 8 appears longer than width being more dorsoventrally curved, and the posterior width is distinctively broader. Whereas, A. dimidiatus fore femora are basal half to two-thirds dark grey, apical length yellow-brown, middle and hind femora near all yellow-brown, when there may have some dark grey on the basal ventral surface. Has slightly grey transparent wings, veins yellow-brown basally that may darken posteriorly to brown, their margins weakly infuscate brown and stigma yellowish and indistinct; frons width in male ranges from 4.5–5.0 x anterior ocular width, and female ranges 6.0–7.0 x anterior ocular width. Occipital macrosetae are all black and range 50–60 on each side for the male, and 35–40 on each side for the female; stem of halter all yellow-brown; frons width in the male ranges from 4.5–5.0 x the width of the anterior ocellus, and the female 6– 7 x the anterior ocular width. Male epandrium 1.6 x as wide as long along midline. The apical setae of the inner gonocoxal process are short and robust. The aedeagus, ventral apodeme anterolateral corners are not with dorsally projecting processes, and its anterior margin is widely bifurcated extending half the length of the flanged section; female, sternite 8 has a rounded appearance and dorsoventrally flattened, and the width of the posterior is comparatively narrow.

Anabarhynchus dimidiatus has two synonymies ( Lyneborg 2001), A. liepae Irwin & Lyneborg, 1989 (newname: Thereva lateralis Walker 1852: 161 , pre. occ.), and Anabarhynchus validus Mann, 1928: 190 (incorrect spelling of genus). Both these synonymies have morphology that conforms to that of A. dimidiatus .

Anabarhynchus venabrunneis keys to couplet 83 in Lyneborg (2001) and can be separated from A. barrington Lyneborg by having frontal pile that is longer than scape, frons width 5.0 x anterior ocellus width in the male, and 5.5 x anterior ocellus width in the female. The male abdominal dorsal surface is covered by dense grey pubescence and lacks black anterior bands, though the female does have black anterior bands. Frontal pile of A. barrington is only about half the scape length, the male frons only 2.0–2.2 x the anterior ocellus width, and the abdominal dorsal surface has distinct black anterior bands. Lyneborg (2001) identified that the female sternite 8 had a pair of deep depressions inside a larger depression, and in the male the sternite 11 (hypoproct) has a dorsoventral orientation, which is evident in both female and male A. venabrunneis ; this species is placed in the dimidiatus species-group.

On KI, A. venabrunneis sp. nov., is widespread along the southern coast of KI, with the two males taken at sandy coastal sites associated with limestone, at both the western and eastern ends of the island. The two known females came from one property between these disparate sites, approximately 5km inland from D’Estrees Bay in a cleared (agricultural) habitat with deep sand formerly supporting mallee heathland. Little is known of the biology of A. venabrunneis and larvae have not been collected. All specimens collected thus far have been caught in October suggesting that the species is most likely encountered in spring.

Figures

FIGURE 8. Anabarhynchus venabrunneis sp. nov. Holotype male (SAMA_29:004654), lateral view. Scale line=1.0 mm. [C. Lemann].

FIGURE 9. Anabarhynchus venabrunneis sp. nov., Holotype male (SAMA_29:004654), frontal view. Scale line=0.5 mm. [C. Lemann].

FIGURE 10. Anabarhynchus venabrunneis sp. nov. Paratype male (SAMA_29:004655). Terminalia: A, epandrium; (left) dorsal view, (right) ventral view. B, (left) gonocoxite dorsal view, (right) ventral view. C, aedeagus dorsal view. D, aedeagus lateral view, (with dorsal view of anterior of ejaculatory apodeme). Paratype female (RGC_13946), E, furca. F, sternite 8 ventral view. Scale line=0.25 mm. [D. Ferguson].