Brachylinga Irwin and Lyneborg

Webb, Donald W. & Metz, Mark A., 2006, A Revision of the New World Genera Brachylinga Irwin and Lyneborg and Lysilinga Irwin and Lyneborg (Diptera: Therevidae: Therevinae) with the Description of a New Genus, Elcaribe Webb, Zootaxa 1288 (1288), pp. 1-241 : 11-12

Brachylinga Irwin and Lyneborg

Brachylinga Irwin and Lyneborg (1981a:202 key, 232 desc., 234 spec. listing; 1981b:519 key). Type species Psilocephala baccata Coquillett by original designation.

Irwin and Lyneborg (1981a:234) listed 12 species under Brachylinga for the Nearctic Region, but several of these species have been moved to Elcaribe gen. nov. in this manuscript. This revision includes 26 valid species of Brachylinga for both the Nearctic and Neotropical regions necessitating a redescription of the genus.

Diagnosis

Brachylinga is characterized by lacking setae on the metakatepisternum; the male distiphallus lacking an subapical hood ( Fig. 167); the male gonostylus with two apical points ( Fig. 98); the male ventral lobe large and wrapping around the gonostylus; the dorsal and ventral apodemes of the male aedeagus flattened dorsoventrally in crosssection; and the female furca lacking a posteromedial projection ( Fig. 187).

Redescription of genus

Moderate sized therevids, males 3.5–7.8 mm (n=170), females 4.3–8.2 mm (n=190).

Head. Ocellar tubercle dark reddish brown, pruinescence dull gray, not raised above level of vertex; setae black, elongate. Males holoptic, females dichoptic. Frons small in males with or without setae, broad in females; black pruinescent band and setae absent lateral to antennal base. Face only slightly projecting beyond eyes. Antenna shorter than length of head; scape cylindrical, length longer than wide, longer than length of pedicel, narrower than width of flagellum, setae absent on medial surface, macrosetae dark brown; pedicel globular, setae dark reddish brown, short, absent on medial surface; first flagellomere expanded then tapering to attenuate apex, second flagellomere cylindrical, third flagellomere tapered apically, apical style short, flagellum longer than wide, longer than length of scape. Parafacial lacking setae. Maxillary palpus cylindrical, apex rounded. Genal setae white, elongate, occasionally with small patch of short, brown to black setae anteroventrally. Occiput convex, black, pruinescence gray; macrosetae dark reddish brown to black. Postocular macrosetae in single row.

Thorax. Macrosetae 2–4 np, 1–2 sa, 1 pa, 0–2 dc, 1–2 sc. Vittae on mesonotum indistinct; postpronotal lobe generally concolorous with mesonotum; prosternum with white, elongate setae in and around central depression. Pleural setae elongate on propleuron, anepisternum, laterotergite, metanepisternum, and scutellum, absent on proepimeron, anepimeron, meron, and metakatepisternum. Wing. Setulae absent on R 1; M 1, M 2, and M 3 originate separately from apex of discal cell; cell cup closed, petiolate; anal angle broadly rounded. Legs. Coxae with setae generally present on posterior half of midcoxa (exception: B. sericeifrons ); hindcoxa with dark reddish brown anterior knob and one posterolateral macroseta. Femoral setae filiform ventrally becoming lanceolate, appressed dorsally; av 0–2:0:0–5, pv 0:0:0–11.

Abdomen. Male terminalia . Tergite 8 ( Figs. 2–24) bilobed, posterior margin emarginate; one pair of sensory sensilla. Sternite 8 ( Figs. 25–47) reduced, 1–2 pairs of sensory sensilla. Epandrium ( Figs. 2–24) quadrate, broad basally, tapering apically; shorter medially than wide; posterolateral margin short, broadly pointed. Cerci ( Figs. 2–24) separated basally, ending distal to posterolateral margin of epandrium. Hypoproct ( Figs. 2–24) quadrate, apicoventral area flat. Hypandrium ( Figs. 48–70) heavily sclerotized. Gonocoxite ( Figs. 25–70) separated medially; gonocoxal apodeme narrow, not extending beyond anterior margin of gonocoxite, inner gonocoxal process absent; ventral lobe ( Figs. 25–47) large, wrapping around medial base of gonostylus. Gonostylus ( Figs. 94–116) with large basodorsal lobe, apical three­fourths falcate, separating apically to form two points; fine short spines present or absent laterally. Aedeagus with dorsal apodeme ( Figs. 117–139) generally quadrate, anterior margin generally truncate; ventral apodeme ( Figs. 140–162) generally narrow, tapering anteriorly; distiphallus ( Figs. 117–139) elongate, generally tapering to narrow apex; ejaculatory apodeme ( Figs. 117–139) slightly bulbous apically, anterior half expanded laterally, not extending beyond anterior margin of dorsal apodeme, in cross­section flattened dorsoventrally. Lateral ejaculatory process large, quadrate to triangular. Female terminalia . Anterior margin of sternite 8 scalloped, membranous; aedeagal guide absent. Median lobe of tergite 9 glossy; setae dark reddish brown (absent on B. sericeifrons ). Furca ( Figs. 186–206), anterior margin closed; posteromedial and anteromedial projections absent.

Immature Stages. The immature stages have not been described for any species of Brachylinga although larvae of Brachylinga baccata , B. chilensis , B. laculata , B. ornatifrons , B. pavida , B. punctifrons , and B. sericeifrons have been reared.

Distribution ( Figs. 207–217)

From Florida north to New York, west to Washington and California in the United States and south to Chile and Argentina in South America .

Habitats and phenology

Brachylinga is primarily distributed in sandy xeric areas, although occasionally found in boreal habitats. It has been handnetted, sweepnetted, collected in Malaise, light (ultraviolet, mercury vapor), Leggett, rotating, suction, and pan traps, and by fogging with an insecticide on lakeshores, beach knolls, coastal dunes, riverbottoms, washes, dry hillsides in an oak zone along a flowing stream, in chaparral, in sand pine, scrub oak and saw Palmetto, in the riparian zone of juniper­pinion woodlands, in mesquite­acacia desert scrub near the coast, in cotton fields, in juniper woodlands, sagebrush flats, and Nothofagus forest, and on various vegetation (alfalfa, Artemisia tridentata Nutt. , Baccharis glutinosa Pers., C ondalia lycioides (A. Gray) Weberb., Erigonum fasciculatum Bentham , Eriogonum fasciculatum var. polifolium (Benthem) Torrey & Gray , Gaillardia sp. , Juglans major (Torr.) A. Heller , Lithrea sp. , Peraphyllum ramosissim Nutt. , Purshia sp. ; Salix sp. , sagebrush, and Sarcobatus vermiculatus (Hook.) Torr. ), and in various colored pan traps in inland dunes. Adults of various species can be collected throughout the year.