Leptodromia immaculata, Barros & Sinclair & De Freitas-Silva & Ale-Rocha, 2024

Barros, Luana M., Sinclair, Bradley J., De Freitas-Silva, Rafael A. P. & Ale-Rocha, Rosaly, 2024, Revision of the genus Leptodromia Sinclair & Cumming, 2000 (Diptera: Hybotidae: Ocydromiinae), with the description of six new species, Records of the Australian Museum 76 (3), pp. 133-150 : 140

Leptodromia immaculata

Barros, Freitas-Silva & Sinclair sp. nov.

urn:lsid:zoobank.org:act:0FB1A592-0822-45D8-B4BA-10E87DE3E326

Figs 11–21 , 42

Diagnosis. Antenna brown. Scutum, pleura and mediotergite yellow, dark brown above halter. Legs yellowish, hind femur with brown subapical band on anterior face.Abdomen yellow with broad, brown anterior half with medial extension.

Description. Holotype male ( Fig. 11 ). Body length: 3.5 mm. Wing length: 3.3 mm ( Fig. 41 ). Head. Ocellar triangle shiny, with 1 pair of short, slender proclinate ocellar setae. Frons shiny, dark brown with pruinosity on lower half. Face with dense grey pruinescence. Antenna ( Fig. 12 ) brown, except inner margin of scape and pedicel paler and shiny; postpedicel elongate, lanceolate, about 2.5 times length of scape and pedicel combined, covered with dense brown microtrichia; arista-like stylus brown, with microtrichia, slightly shorter than length of postpedicel. Proboscis yellow; palpus oval, covered with dense pale pruinosity and 1 long, slender yellow seta near middle. Occiput dark brown, shiny ( Figs 13, 14 ); two rows of short, slender yellow setae, 1 row postoculars and 1 row occipital, lower setae slightly longer. Thorax. Prosternum narrow (prosternum is not fused to the proepisternum not forming a precoxal bridge). Antepronotum yellow with row of short, slender yellow setae. Scutum yellow ( Fig. 14 ). Scutellum, mediotergite and pleura yellow with brown spot above halter. Postalar callus with 1 long, strong seta and 1 short, slender anterior setula. Wing ( Fig. 21 ). Broad, membrane slightly infuscate; pterostigma brown, elongated, and narrow, situated at apex of cell c. Cell dm approximately 4 times longer than wide, M 1 very short, longer than crossvein r-m, M 2 and M 4 ending at wing margin; cell cua two-thirds length of cell bm. Halter whitish yellow. Legs. Slender, yellowish brown, except apex of mid and hind femora black, tarsi slight darker. Mid and hind tarsomeres 3–5 slightly broader than fore tarsomeres, ventrally flattened. Hind femora with brown subapical band on anterior face ( Figs 11, 15 ). Fore femur with row of pale anteroventral setae. Mid femur with row of pale anteroventral setae; 1 long, dark subapical anterodorsal seta. Hind femur with rows anteroventral and posteroventral of pale and slender setae. Fore tibia without outstanding setae. Mid tibia with 2 anterodorsal setae: 1 near base and 1 near mid-length and 1 posterodorsal seta near mid-length; apex of 1 strong anteroventral and 1 strong posteroventral setae. Hind tibia with 2 anterodorsal black and strong setae: 1 near base and 1 near mid-length; apex with 1 strong posteroventral seta. Abdomen ( Fig. 16 ). Covered with short, yellow, slender setae. Yellow, with broad brown anterior band on syntergite 1+2 and tergites 6–7, tergite 3–5 with broad anterior band with short medial extension. Male terminalia ( Figs 17–20 ): Hypandrium short, small, slightly narrowing toward apex, with deep concavity in middle on apical margin forming bilobed apex and several short, slender setae. Phallus short, about same length as epandrial lamella; phallic shaft strongly curved near base, cylindrical, without protuberances; apex expanded, cup-like.Articulated distiphallus as long as phallic shaft with single dorsal sclerite with bifid apex; ejaculatory apodeme one-third length of hypandrium. Epandrial lamella subtriangular, with several short and slender setae on surface, longer on apical margin; right epandrial lamella 1.5 longer than wide, with several thickened setae on inner margin near cercus; left epandrial lamella 1.5 longer than wide with slight concavity and expanded section laterodorsally, bearing several thickened setae; dorsal connection between lamellae short and very narrow. Right surstylus longer than left, 3x longer than wide, apex attenuated; left surstylus shorter than left, strongly bent, with sharp apex; several short, slender setae on both surstyli. Cerci symmetrical short, digitiform-like, weakly sclerotized, covered with short and slender setae. Bacilliform sclerite asymmetrical, with short, slender setae on inner margin. Basal margin of subepandrial sclerite truncate, deeply split forming rounded concavity at middle; hypoproct divided in two small, narrow sclerites. Female. Similar to male, except mid and hind tarsomeres not expanded and flattened. Abdominal tergites 2–6 with dark medial extension. Female terminalia: not dissected.

Type material. Holotype ♂, labelled: “ Australian Museum / K 608799”; AUSTRALIA: Tasm. [Tasmania]:/ Mt. Barrow Rd. 890m [41°22'3"S 147°25'50"E]/ 15–17.ii.1980 / Nothofagus, etc./ A. Newton, R. Thayer”; “ HOLOTYPE / Leptodromia / immaculata / Barros, Freitas-Silva & Sinclair [red label]” ( AMS) . Holotype in good condition. Paratypes: Australia. Tasmania: same data as holotype (1 ♂ K 608309, AMS) ; Arve R., 43°09'S 146°48'E, 3.ii.1983, ypans, I.D. Naumann, J.C. Cardale (1 ♀ K 608801, AMS) ; Cradle Mtn cpgd, 880 m [41°34'38"S 145°56'6"E], alpine forest, ypans, 20–22. ii.1994, B.J. Sinclair (1 ♂, CNC) ; Franklin River crossing, Lyell Hwy [-42.215, 146.019], 16.i.1960, D.K. McAlpine (1 ♂ K 608299, AMS) ; Frodshams Pass [42°49'6"S, 146°23'20"E], nr. Mt. Wedge , 4–5.ii.1989, rainforest, ypans, D.J. Bickel (2 ♂ K 608297, K 608298, AMS) ; Hartz Mtns [43°14'S, 146°45'E], 800 ft, 20.i.1960, D.K. McAlpine (2 ♂ K 608294, AMS) ; Hellyer Gorge , 41°16'S 145°37'E, 17.i.1983, ypans, I.D. Naumann, J.C. Cardale (1 ♀ K 608306, AMS) ; 10 kmS Hellyer River [41°19'S, 145°35'E], 10.i.1984, L. Masner (2 ♂, 1 ♀, CNC; 1 ♂, INPA) ; Lake St. Clair NP [-42.122, 146.216], 750 m, 12.i.1984, L. Masner (2 ♂, 4 ♀, CNC) ; Mt. Barrow , 1500 ft, 24.i.1960, D.K. McAlpine (1 ♂ K 608295, AMS) ; same data except, 3000 ft, 25.i.1960 (1 ♂ K 608296, AMS) ; Mt. Barrow , 11 km E by N Nunamara, 41°23'S 147°25'E, 30.i.1983, I.D. Naumann, J.C. Cardale (2 ♀ K 608305, K 608304, AMS) ; Mt. Field NP, 3–16.i. 1984, 200 m, L. Masner (7 ♂, 6 ♀, CNC) ; Mt. Field NP [42°40'S, 146°42'E], riparian veg., 180 m, 18.ii.1994, B.J. Sinclair (1 ♀, CNC) ; Mt. Field NP, Mariette Falls [-42.71, 146.65], 13.i.1984, L. Masner (2 ♂, 2 ♀, CNC) ; 5 km SEbyE Redpa , 40°57'S 144°49'E, 18.i.1983, I.D. Naumann, J.C. Cardale (1 ♀ K 608300, AMS) ; Shoobridge Bend, Mt. Wellington , 42°54'S 147°15'E, 5.ii.1983, I.D. Naumann, J.C. Cardale (1 ♂ K 608302, 1 ♀ K 608301, AMS) .

Distribution. This species is known only from Tasmania, where it is widely distributed ( Fig. 42 ).

Etymology. From Latin im (without) and macula (spot), in reference to the absence of a spot on the scutum.

Figures

Figure 42. Geographical records of Leptodromia Sinclair & Cumming, 2000.

Figures 11–16. Leptodromia immaculata sp. nov. (11) Male holotype, lateral habitus; (12) Male holotype, antenna; (13) Male occiput, dorsal view; (14) Male scutum, dorsal view; (15) Male hind femur, lateral view; (16) Male abdomen, dorsal view.

Figures 17–20. Leptodromia immaculatasp. nov., male terminalia (Holotype).(17) Ventral view; (18) Dorsal view; (19) Left lateral view; (20) Right lateral view.Abbreviations: distph = distiphalus; epand = epandrium; hypd = hypandrium; ph = phallus; hyprct = hypoproct; sbepand scl = subepandrial sclerite. Scale bars= 0.1 mm.

Figures 21–22. Wings of LeptodromiaSinclair & Cumming, 2000.(21) Leptodromia immaculatasp. nov.; (22) Leptodromia t-maculatum sp. nov. Abbreviations: Rs = radial sector; R1 = anterior branch of radius; R2+3 = second branch of radius; R4+5 = third branch of radius; M1 = first branch of media; M4 = fourth branch of media; CuA+CuP = anterior branch of cubital vein + posterior branch of cubital vein; CuA = anterior branch of cubital vein; br = basal radial cell; bm = basal medial cell; dm = discal medial cell; cua = anterior cubital cell.

Figures 36–41. Leptodromia t-maculatum sp. nov., terminalia. (36) Male holotype, ventral view; (37) Male holotype, dorsal view; (38) Male holotype, left lateral view; (39) Male terminalia, right lateral view; (40) Female terminalia, ventral view; (41) Female terminalia, dorsal view. Abbreviations: cerc = cercus; ST = sternite; T = tergite. Scale bars= 0.1 mm.