Amblypsilopus megastoma, Bickel, 2019

Bickel, Daniel J., 2019, The Amblypsilopus amnoni and megastoma groups in New Guinea (Diptera: Dolichopodidae: Sciapodinae), Israel Journal of Entomology (Oxford, England) 49 (2), pp. 195-214 : 211-213

Amblypsilopus megastoma n. sp.

( Figs 18–21)

LSID: urn:lsid:zoobank.org:act:2C943C29-0323-453B-A76F-854C23ABC717 .

Etymology: The specific epithet is derived from Greek mega, meaning large, and stoma for mouth, in reference to the enlarged proboscis of this species.

Description: Male. Length 4.3 mm, wing 4.5× 1.4 mm ( Fig. 18).

Head ( Fig. 20). Vertex, frons, shining metallic blue, face mostly metallic blue-green, with a dusting of fine yellowish pruinosity; clypeus pale yellow; row of short black orbital setae and postvertical seta dorsalmost; strong diverging ocellar setae and pair short posterior hairs on ocellar tubercle black; short black hair-like vertical seta on lateral slope of vertex; upper face slightly bulging, palp yellow with brown setae; proboscis pale yellow; with pale yellow hairs, but labella greatly extended and expanded, comprising two trapezoidal translucent white glabrous lips with pseudotracheae clearly visible externally; antenna yellow with dark brown arista; scape short; pedicel with subapical coronal of short black setae and stronger dorsal seta; postpedicel rounded, subrectangular, with apical arista, length almost twice head height, and simple; ventral postcranium with short white hairs.

Thorax. Almost entirely yellow, without pruinosity, but mesonotum with shining metallic blue reflections, and scutellum dorsally dark blue but with yellow dorsal rim and yellow ventrally; setae black; 2 pairs of long ac, with short pair anteriormost, 2 strong posterior dc and 4 weak hair-like dc anteriad (MSSC); 1 pa, only 1 sa, only 1 sr, 2 npl, 1 hm, and 1 pm; median scutellar setae strong, laterals absent.

Legs. All coxae and legs yellow with distal tarsomeres infuscated; CI with 3 black yellow distolateral setae and short yellowish hairs: CII with 2 black anterolateral setae and black anterior hairs; CIII with black lateral seta at ⅓; legs with short black vestiture and mostly bare of major setae; I: 4.7, 6.7, 9.0/1.7/1.8/0.8/0.7; TI with short pale curved posterior seta at 9/10, just before apex (MSSC); It 1 longer than TI; It 5 black, flattened and expanded into apical pinnate flag (MSSC); II: 5.3, 9.2, 8.5/1.9/1.5/0.8/0.5; FII with short subapical pv seta; TII with short ad setae at ⅒, with short anterior setae at ¼, ½ and ¾, and with shorter pd at ½ and ¾, with apical corona of ad, av, pv and dorsal setae; III: 7.2, 12.8, 5.8/2.0/1.5/1.0/0.5; TIII with strong ad at ⅛, short av setae, some 10 short spaced anterior setae along distal three-quarters, 5 spaced short dorsal setae along length, and with corona of short ad, av and pv setae.

Wing. Hyaline, elongate; vein M 1 in right-angled arch M 1 to approach R 4+5 and join costa anterior to wing apex; dm–cu straight; CuAx ratio 1.3; lower calypter pale yellow with fan of black setae; haltere yellow.

Abdomen. Tergite 1 yellow; tergites 2–6 mostly yellow, but each with ovate dorsal metallic blue markings and matt brown along tergal margin; tergites 7 and 8 yellow; tergites with short black vestiture and row long black marginal setae; hypopygium ( Fig. 19) basally yellow and with distal half and hypandrium dark brown, but surstylus and phallus yellowish; epandrium subrectangular; surstylus as short projecting arm; cercus yellow and flagelliform, with fine yellow hairs.

Female. Similar to male, except as noted: vertical seta strong; face not bulging; clypeus wider and almost adjacent to sides of eyes; proboscis ( Fig. 21) also extended but narrower; blade-like; 2 pairs of strong ac; dc also like male, with 2 strong posterior setae and 2 faint hairs anteriad; legs without MSSC; It 1 longer than TI; It 5 unmodified; abdominal coloration similar.

Holotype: ♂ Papua New Guinea: Western Province, Star Mtns, Camp 2, 5°10'S 141°15'E, 700–850 m, ii–iii.2013, yellow pans, C. Muller ( AMS).

Paratype: 1♀, same data as holotype .

Other material examined: Papua New Guinea: 2♀, Madang Province, Baitabag , 5°07'30"S 145°46'00"E, 70 m, 27–29.vii.1999, yellow pans, R. Kitching ( AMS) .

Remarks: Amblypsilopus megastoma is known from Papua New Guinea, 700– 800 m in the Star MoUntains, Western Province and from two possible females from lowland Madang Province. Males have the labella enlarged into trapezoidal plates, whereas in females the labella are enlarged but narrower. Males have leg I tarsomere 5 is modified into a black pinnate flag. Both sexes have a yellow clypeus and the basitarsus of leg I longer than tibia I.