Ommatius limbatus, Daniels, Greg, 2017

Daniels, Greg, 2017, Australian species of Ommatius Wiedemann (Diptera: Asilidae) with an anepimeral bristle, Zootaxa 4231 (4), pp. 535-563 : 549-551

Ommatius limbatus sp. nov.

( Figs 9 , 61–68 , 113 )

Diagnosis. Distinguished by the lack of marginal scutellar setae. Additionally, males have a dorsal flange on apical half of the epandrium.

Type material. HOLOTYPE ♂, AUSTRALIA. Queensland. 19°07.8’S 145°20.2’E / Gregory Development Rd , / 14 km NW Clarke Riv. 394 m / 17 Dec 2006 – 15 Feb 2007 / S. Wright. malaise, 14734 / vinescrub on limestone (QM Reg. No. T 207015). PARATYPES. Queensland. 1 ♂, same data as holotype (QM) ; 1 ♂, - 21.688° Sx 146.924°E Nairana NP (NR1M). 254m. 25.x.–10.xi.2010. 18491 Lambkin, Starick, H. & D. Hanrahan. Open Eucalypt Woodld/spinifex. Malaise. T 228471, (QM).

Non-type material examined. Queensland. 1 ♀ [abdomen damaged], 19°07.8’S 145°20.2’E / Gregory Development Rd , / 14 km NW Clarke Riv. 394 m / 17 Dec 2006 – 15 Feb 2007 / S. Wright. malaise, 14734 / vinescrub on limestone (QM).

Description. Male. Body length, 5.4–5.9 mm; thoracic length, 1.5 mm; wing length, 4. 0–4.2 mm. Head. Face gently rounded, barely protruding beyond eyes in profile and with silvery-white tomentum. Mystax with two vertical rows of long thin bristles, the uppermost 2 or 3 pairs black, remainder white; lower half of face and epistomal margin with weaker white setae. Ocellar tubercle with a pair of long erect or proclinate setae and a few shorter proclinate setae anteriorly. Occiput with several long black setae dorsally, weakening and becoming white ventrally. Flagellum about half as long as pedicel and conical. Style with setae in two ranks. Thorax. Groundcolour black, lateral pleural sclerites with fine grey tomentum; mesonotum with brownish tomentum, becoming silver-grey laterally; postpronotal lobe shining and covered with very fine tomentum and with a few long weak, whitish setae. Acrostichal setae seemingly absent but when viewed in profile setae are visible. Presutural dorsocentral bristles absent; 2 or 3 pairs of post-sutural dorsocentral bristles present. Scutellum dorsally with sparse scattered setae and a pair of weak marginal bristles. Anepisternum bare, rarely with weak setae posteriorly. Anepimeral seta present. Wing ( Fig. 113 ). With microtrichia uniformly distributed over most of wing, basal third with some cells with clear areas. Costal bulge absent. Vein R4+5 arising almost perpendicular to vein R3. Legs. Femora black, narrowly orange-brown at apex. Tibiae orange-brown, darker apically, hind tibia dark brown-black on apical half. Fore and mid metatarsi orange-brown, hind metatarsus brown-black; remainder of tarsal segments brown-black. Fore femur with a ventral row of long, weak setae. Mid femur with an anterior bristle at about middle and another at apical third; a posteroventral row of 4 or 5 weak bristles and a ventral row of weak bristles. Hind femur with an anterior bristle at about middle and another at apical third; an ventral row of 4 or 5 short, stout bristles and a posteroventral row of 7 or 8 long fine bristles. Fore tibia with 2 long posteroventral setae; a short subbasal dorsal seta; a ventral row of 6 or 7 setae. Mid tibia with a stout anterodorsal bristle at about apical fourth, a similar anteroventral bristle at about basal third, a ventral seta at about apical third and a row of 4 or 5 short ventral setae. Hind tibiae with a subapical, anterodorsal bristle and another longer one at apical third; a posterodorsal bristle at about middle; 2 anteroventral bristles, one near the middle the other at apical fourth. Abdomen. Deep brown to black, with similarly coloured tomentum, tergites 2–7 narrowly greyish tomentose basally and apically, posterolateral bristles tergites 2–6 pale and thin and becoming weaker on each successive tergite; sternites deep brown to black, with pale, semi-erect setae. Terminalia ( Figs 61–68 ). Deep brown to black, uniformly covered with fine setae. Tergite 8 ( Fig. 68 ) with a slightly concave posterior margin and a deeply emarginate anterior margin; posterior margin with several long, stout bristles. Sternite 8 ( Fig. 67 ) with straight posterior margin and concave anterior margin; posterior margin about half length of anterior margin. Epandrium ( Fig. 65 ) not fused; distally with a dorsal flange-like process. Hypandrium and gonocoxite ( Fig. 66 ) fused at base; gonocoxite incurved and upturned distally and with a large, dorsal apodeme just beyond middle; hypandrium tongue-like with a broad base, marginally with a dense fringe of short setae along length. Gonostylus ( Fig. 66 ) attenuate, with short, stout bristles ventrally along distal half. Aedeagal complex ( Fig. 64 ): distiphallus short and stout, dorsally upturned apically; basiphallus with a large, dorsal hood anteriorly and distally with a ventral prong; ventral aedeagal apodeme gently curved.

Female. Differs from male as follows: thoracic length, 1.6–1.8 mm; wing length, 5.2–5.6 mm. Abdomen. Damaged.

Etymology. The specific name is derived from the Latin limbatus , ‘bordered’, referring to the flange-like rim on the male epandrium.

Distribution ( Fig. 9 ). Central-eastern Qld.

Figures

FIGURES 4 – 9. Distribution of Ommatius spp. with anepimeral bristle. (4). O. radamnis sp. nov. (red circle) and O. aquilonaris sp. nov. (green circle); (5). O. musselbrookensis sp. nov.; (6). O. melasmus sp. nov.; (7). O. burwelli sp. nov.; (8). O. imaginis sp. nov.; (9). O. limbatus sp. nov.

FIGURES 61 – 68. Ommatius limbatus sp. nov. Male terminalia. (61). Lateral view; (62). Dorsal view; (63). Ventral view. (64). Aedeagal complex; (65). Epandrium ventral view; (66). Gonostylus, gonocoxite and hypandrium; (67). Sternite 8; (68). Tergite 8. Abbreviations: dist, distiphallus; ejap, ejaculatory apodeme Scale bar, 0.25 mm.

FIGURES 107 – 116. (107 – 109). Terminalia of Ommatius radamnis sp. nov. (107). Genital fork; (108). Sternite 8; (109). Tergite 8. (110 – 116). Right wing of male Ommatius spp. (110). O. aquilonaris sp. nov.; (111). O. burwelli sp. nov.; (112). O. imaginis sp. nov.; (113). O. limbatus sp. nov.; (114). O. melasmus sp. nov.; (115). O. musselbrookensis sp. nov.; (116). Ommatius radamnis sp. nov. (female). (110). Scale bar, 1.00 mm and as indicated.