Hydropeza angulata, 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 : 4-10

Hydropeza angulata sp. nov.

Figs 7, 9

Type material. Holotype ♂, labelled: “AUST: N.QLD:/ 31.6km / up Mt. Lewis Rd. , 860m / 21.iv.1994, cascading/ creek, B. J. Sinclair / 16°30'S 145°17'E ”; “ HOLOTYPE / Hydropeza / angulata/ Sinclair [red label]” (AMS) . Paratypes: Queensland: 1♂, 2♀♀, 14.7 km up Mt. Lewis Rd. , 860 m, 22.iv.1994, cascading ck, 16°30'S 145°17'E, B. J. Sinclair (CNC) ; 1♂, 4♀♀, same data as holotype (AMS) .

Diagnosis. This species is distinguished from other Queensland species by acrostichal setae confined anteriad of an imaginary line connecting the first (anteriormost) dorsocentral setae; arista-like stylus 2.5× length of postpedicel; male scutellum with 0–1 pair of elongate discal setae; male mid femur with row of short 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 unbranched, with apex bent at right angle medially. Females are distinguished from all other species by discal setae mostly absent on the scutellum and segment 8 generally retracted within the abdomen and flattened.

Description. Head and abdomen dark brown, thorax brown with paler patches; coxae brownish yellow, legs progressively darker towards tips. Wing length 4–4.2 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, pedicel and inner base of postpedicel slightly paler than remaining postpedicel; scape short and slender, slightly longer than length of globular pedicel; postpedicel not greatly prolonged, less than 2× longer than scape, basal portion elongate-oval, 2× longer than tapered apical portion; arista-like stylus 2.5× longer than postpedicel, concolorous with postpedicel. Proboscis stout and robust, extended beyond mid-length of fore coxa, directed posteriorly; palpus half-length of proboscis, clothed in long pale and dark setae; apex of palpus rounded; apical third of palpus 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; 2–4 acrostichal setulae confined anterior to 1st dorsocentral setae, less than 0.5× length of dc; pprn with 1 seta and 1–2 short setulae; 1 long presut spal; 5 uniserial dc, about subequal in length with several setae interspersed; 3 npl; 1 long psut spal and several shorter anterior setae; 1 pal seta and 1–2 pale setulae; 1 pair of sctl, with 1 pair of finer outer marginal setae; disc of scutellum with 0–1 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 (subequal in thickness to mid femur), with row of 2 stout anterior setae at apical fifth; 4–6 posterodorsal setae, apical 2 setae distinctly stouter. Fore tibia with 3 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; Figures 7–8. Known distribution of the Hydropeza species : (7) H. angulata ; (●), H. queenslandica ; (Ê); (8) H. cornuta ; (), and H. curvata ; (Ɨ). Shaded areas indicate land above 700 m in altitude.

1 long basal ventral, 2–4 shorter ventral setae at middle and apex. Mid femur with row of 4 anterodorsal setae stouter towards apex; 1 anterior and 2 posterodorsal setae on apical third; basal half with row of 7–10 short, stout posteroventral setae, less than width of femur; apex with 1 anterior, 1 dorsal and 1 posterior preapical seta. Mid tibia with width reduced on ventral apical third, with row of 9–11 short spine-like setae; apex with 1 short, spur-like ventral and anterodorsal seta; 1 anterodorsal and 2 posterodorsal setae; apex with 1 dorsal seta. Mid tarsomere 1 with 1 long anteroventral and 1 posteroventral basal seta; apex with several preapical setae. Hind femur greatly inflated, nearly 2× broader than fore or mid femora, without erect dorsal setae; with anteroventral row of stout setae along apical third; apical fourth with 2–6 anterodorsal, 1–2 posterodorsal, 1 anterior and 1 posterior seta. Hind trochanter without spine-like anteroventral setae. Hind tibia with 1 anterodorsal, 1 anteroventral and 1 posterodorsal seta; 1 preapical anterodorsal and 1 apical anteroventral seta; apical fourth with dense posterior setae. Hind tarsomere 1 without erect setae. Fore and mid tarsomeres slightly longer than tibia; ventral apical margin of tarsomere 4 of fore and midlegs somewhat pale, flattened and expanded; tarsomere 4 and apical third of tarsomere 3 of hindleg slightly 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; cell dm truncate, longer than cell bm; CuA + CuP reduced to streak. Halter brown.

Abdomen. Tergites and sternites clothed in setae; setae Figures 19–20. Known distribution of the Hydropeza species : (19) H. divaricata sp. nov. (●) and (20) H. intricata sp. nov. (Ɨ). Shaded areas indicate land above 700 m in altitude.

of posterior margin overlapping more than half length of following tergite. T8 broad, nearly one-half length of T7; posterior marginal setae slender, some 1.5× length of tergite.

Terminalia ( Fig. 9 ). Cercus projected horizontally, shorter than epandrium, not forked or subdivided; apex sharply bent at right angle medially, nearly touching opposing cercus. Epandrium broad with scattered setae. Surstylus short, with broadly rounded apex, not arched medially; inner margin with cluster of some 8 stout setae. Hypandrium subrectangular broad; apical margin not notched; gonocoxal apodeme broad, rounded; postgonite broad, short and L-shaped, touching opposing postgonite medially. Phallus broad with apex inflated; ejaculatory apodeme straight, longer than gonocoxal apodeme.

Female. Similar to male except as follows: scutellum with 1 pair of discal setae; mid femur lacking row of stout posteroventral basal setae; mid tibia not narrowed apically, lacking row spine-like setae; hind femur not strongly inflated, lacking anteroventral row of stout setae. Terminalia (not dissected): segment 8 not inflated, broad; cercus slightly longer than epiproct, nearly 2× longer than wide; broad with rounded apex.

Distribution. This species is recorded from above 800 m on Mt. Lewis, Queensland (Fig. 7).

Etymology. The specific name is from the Latin angulatus (with angles), in reference to the right angle bend of the male cercus.

Figures 21–22. Known distribution of the new Hydropeza species : (21) H. aptera sp. nov. (Ê); H. unguicula sp. nov. (¾); and (22) H. tasmanica sp. nov. (●).

Figures

Figures 9–12. Male terminalia of Hydropeza, lateral view. (9) H. angulata (inset showing inner apex of cercus). (10) H. aptera. (11) H. cornuta. (12) H. curvata. Abbreviations: cerc, cercus; ej apod, ejaculatory apodeme; goncx apod, gonocoxal apodeme; pgt, postgonite; ph, phallus; sur, surstylus. Scale bars = 0.1 mm.