Hydropeza divaricata, Sinclair, 2016

Sinclair, Bradley J., 2016, Revision of the Australian species of Hydropeza Sinclair (Diptera: Empididae: Ragadinae subfam. nov.), Records of the Australian Museum 68 (1), pp. 1-22 : 14

Hydropeza divaricata sp. nov.

Figs 19, 23

Type material. Holotype ♂, labelled: “AUST: N.QLD:/ Bellenden Ker N.P./ Bartle Frere Tr., 200m / 12–21.iv.1994, malaise/ B. J. Sinclair / 17°25'S 145°51'E ”; “ HOLOTYPE / Hydropeza / divaricata/ Sinclair [red label]” (AMS) . Paratypes: Queensland: 7♂♂, 9♀♀, same data as holotype (AMS) ; 5 ♂♂, 3♀♀, 4 km up Mt. Edith Rd, 800 m, Danbulla St. For., MT across ck, 22–27.iv.1994, 17°05'S 145°38'E, B. J. Sinclair (CNC) ; 3♂♂, 2♀♀, Mt. Hypipamee NP, 960 m, Barron R., 27.iv.1994, 17°26'S 145°29'E, B. J. Sinclair (CNC) .

Diagnosis. This species is distinguished from other Queensland species by acrostichal setae extending posterior to (level of) second dorsocentral setae; male scutellum with at most a pair of elongate discal setae; male mid femur with short row of basal posteroventral setae and mid tibia with short row of spine-like setae on apical third; male hind trochanter without spine-like anteroventral setae; and male cercus deeply forked, U-shaped. Females are distinguished from all other species by 1–2 pairs of discal setae on the scutellum and acrostichal setae extending posterior to (level of) second dorsocentral setae.

Description. Head and abdomen dark brown, thorax brown with paler patches; coxae brownish yellow, legs progressively darker towards tips. Wing length 3.3–4 mm.

Male. Head. Ocellar setae very long, erect, divergent, inserted posterior to anterior ocellus; ocellar tubercle with some long setulae; postocellar seta stout and dark; upper postocular setae stout and dark, lower setae fine and slender; postgenal setae similar to lower postoculars. Face without setulae. Scape and pedicel slightly paler than postpedicel; scape short and slender, slightly longer than length of globular pedicel; postpedicel not greatly prolonged, 3× longer than scape, basal portion elongate-oval, longer than slender, straight apical portion; arista-like stylus slightly longer than postpedicel, concolorous with postpedicel. Proboscis stout and robust, extended slightly beyond mid-length of fore coxa, directed posteriorly; palpus less than half length of proboscis, clothed in long pale setae; apex of palpus rounded; apical third of palpus somewhat flattened with dense pubescence.

Thorax. Clothed in fine pruinescence; mesonotum brown, with postpronotal lobe, lateral margin and postalar ridge pale brown; pleura paler than notum, pale along sutures. Setae generally long and stout; acrostichal setulae extending between 2nd and 4th dorsocentral seta, less than 0.5× length of dc; pprn with 1 seta and several short setulae; 1 long presut spal; 5 uniserial dc, about subequal in length, with 2–3 intermixed nearly subequal setae; 3 npl; 1 long psut spal and 1–2 finer setae; 1 pal seta; 1 pair of sctl, with 2 pairs of finer outer marginal setae; disc of scutellum with 1 pair of long setae. Antepronotum with pair of pale setulae.

Legs. Coxae and femora ventrally yellowish-brown; remaining segments increasingly darker apically. Inner anterior margin of fore coxa with some 15–20 dark, variously lengthened and thickened spine-like setae, mostly concentrated apically; basal most seta longer than width of coxa. Anterior surface of mid and hind coxae with long brown setae. Legs clothed in very long setae as typical for genus, especially ventral faces. Fore femur straight, inflated (narrower than hind femur), with row of 2 stout anterior setae at apical fifth; 5–6 posterodorsal setae, stouter towards apex. Fore tibia with 2 anteroventral setae on apical third; 2 anterodorsal and 2 posterodorsal setae; 1 anterodorsal preapical seta. Fore tarsomere 1 with 1 basal anteroventral and 1 preapical anterovental seta, more than 2× width of segment; 1 long basal ventral and 1 shorter ventral seta on basal third. Mid femur with 2–3 anterodorsal setae, 1 anterior seta and 1 posterodorsal seta on apical third; basal half with row of 4–5 stout posteroventral setae; apex with 1 anterior and 1 posterior preapical seta. Mid tibia with width reduced on ventral apical third, with row of 8 short spine-like setae; apex with short spur-like ventral seta; 1 anterodorsal and 1 posterodorsal seta near mid-length; 1 basal posterodorsal seta; apex with 1 dorsal and 1 posterior seta. Mid tarsomere 1 with 1 long anteroventral basal seta. Hind femur inflated, slightly broader than fore femur, without erect dorsal setae; with anteroventral row of stout setae along entire length; apical fourth with 2 anterodorsal, 1 anterior and 1 posterior seta. Hind trochanter without spine-like anteroventral setae. Hind tibia with 2 anterodorsal and 4–5 posterodorsal setae; 1 preapical anterodorsal and 1 apical anteroventral seta; apical fourth with dense posterior setae. Hind tarsomere 1 without erect setae. All tarsomeres longer than tibia; ventral apical margin of tarsomere 4 of fore and midlegs somewhat pale, flattened and expanded; tarsomere 4 of hindleg not laterally compressed ventrally; tarsomere 5 of each leg lacking dorsoapical extension.

Wing. Infuscate with 1 long basal costal seta, longer than sctl; all veins lacking setulae; R 4 and R 5 distinctly divergent apically; bm-m complete, but weakened proximally; cell dm truncate, subequal in length to cell bm; CuA + CuP reduced to streak. Halter brown.

Abdomen. Tergites and sternites clothed in setae; setae of posterior margin overlapping more than half length of following tergite. T8 broad, one-third length of T7; posterior marginal setae slender, less than twice length of tergite.

Terminalia ( Fig. 23 ). Cercus elongate and lying along dorsal edge of epandrium, deeply forked, U-shaped; apex of upper branch rounded, arched medially; lower branch longer than length of upper. Epandrium narrow, tapered apically. Surstylus weakly differentiated, apex rounded, not prolonged; ventral margin with row of stout setae. Hypandrium keellike, not greatly prolonged; apical margin truncate without medial notch; gonocoxal apodeme short, rounded; postgonite digitiform, divergent with arched, rounded apex. Phallus broad, apically flattened and spoon-shaped; ejaculatory apodeme L-shaped, longer than gonocoxal apodeme.

Female. Similar to male except as follows: scutellum with 1–2 pairs of discal setae; mid femur lacking row of stout posteroventral basal setae; mid tibia not narrowed apically, lacking row of spine-like setae; hind femur not strongly inflated, lacking anteroventral row of stout setae. Terminalia (not dissected): cercus slightly longer than epiproct, broad with rounded apex.

Distribution. This species is recorded from northern Queensland sites at 200 m and above 800 m (Fig. 19).

Etymology. The specific name is from the Latin divaricatus (spread apart, separate, fork), in reference to U-shaped male cercus.

Remarks. A single female specimen was collected at Cape Tribulation (Little Cooper Ck, 75 m, 16°10'S 145°27'E), but a male from this locality is required to confirm its identity.

Figures

Figures 23–25. Male terminalia of Hydropeza, lateral view. (23) H. divaricata. (24) H.intricata. (25) H. queenslandensis.Abbreviations:cerc, cercus; ph, phallus; pgt, postgonite; sur, surstylus. Scale bars = 0.1 mm.