Brachylinga concava Webb, 2006

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 : 70-73

Brachylinga concava Webb spec. nov.

( Figs. 10, 33, 56, 79, 102, 125, 148, 171, 192, 214)

Etymology Concavus (Latin) = hollowed or arched inward. This name is used as an adjective and

refers to the deeply emarginate posterior margin of the hypoproct.

Diagnosis

Brachylinga concava is taxonomically associated with B. bicolor and B. divaricata in lacking setae on the katepisternum; in having the postocular, mesonotal, and coxal macrosetae dark reddish brown; in having the male parafacial black ventrally, silver dorsally; and in having the halter knob yellow. Brachylinga concava differs from B. bicolor and B. divaricata in having the apical margin of the hypoproct ( Fig. 10) deeply emarginate and the gonocoxite in lateral view ( Fig. 171) with the basal half oval, the apical half attenuate. Females of B. bicolor , B. concava , B. divaricata , and B. ornata are indistinguishable based on external characters. Internally B. bicolor , B. concava and B. ornata have the spermathecal ducts directed anteriorly ( Figs. 188, 192, 199) while in B. divaricata the spermathecal ducts are directed laterally before bending at a right angle and continuing anteriorly ( Fig. 194).

Description of male holotype (MEI 007482)

Body length 6.0 mm.

Head. Length 0.76 mm. Ommatidia smaller ventrally and laterally. Frons pruinescence white ventrally, black dorsally with white pruinescence separating black area medially; setae black. Antenna/head length 0.76; scape black, pruinescence gray, pedicel and flagellum dark brown, base of first flagellomere dark yellow; scape length 0.16 mm, width 0.11 mm, length/width 1.5, scape/pedicel length 2.0, scape/flagellum width 0.69, setae pale yellow, sparse; pedicel length 0.08 mm, length/width 0.7; flagellum length 0.36 mm, width 0.16 mm, length/width 2.3, flagellum/scape length 2.3. Parafacial pruinescence black, dorsal third silver. Maxillary palpus dark reddish brown; length 0.40 mm, length/ width 5.0; setae pale reddish brown. Genal setae white. Occipital setae white becoming pale yellow, appressed, lanceolate dorsally. Postocular macrosetae dark reddish brown.

Thorax. Macrosetae dark reddish brown, 3 np, 2 sa, 1 pa, 2 dc, 2 sc. Mesonotum brownish gray; setae black, short intermixed with pale yellow, lanceolate, appressed setae. Pleuron pruinescence gray; setae white on propleuron, anepisternum, laterotergite, metanepisternum, and scutellum, absent on katepisternum. Wing. Membrane pale gray; veins pale brown; length 4.8 mm, width 1.5 mm, length/width 3.2; pterostigma pale yellow, narrow; cell m 3 closed, petiolate. Halter pale yellow. Legs. Coxa setae white, present on posterior surface of midcoxa; macrosetae dark reddish brown. Femora dark reddish brown; ventral setae white on fore­ and midfemora intermixed with dark brown setae on forefemur; av 0:0:4, pv 0:0:7. Tibiae dark yellow, apex reddish brown. Tarsomeres 1–2 dark yellow, apex dark reddish brown; 3–5 dark reddish brown.

Abdomen. Reddish brown, paler posteriorly, pruinescence white, dense; dorsal setae white, appressed; lateral setae white, erect. Terminalia (MEI 072889) yellow. Tergite 8 ( Fig. 10), narrow medially (0.03 mm); setae pale yellow, continuous across posterior margin. Sternite 8 ( Fig. 33), sides divergent laterally, posterior margin moderately emarginate. Epandrium ( Fig. 10), sides rounded, setae pale yellow. Cercus ( Fig. 10), ending basal to apex of hypoproct; covered with fine spicules. Hypoproct ( Fig. 10), posterior margin deeply emarginate, ending distal to apex of cercus; covered with fine spicules. Gonocoxite ventral view ( Fig. 33), broad basally, rounded laterally, median margin straight, posteromedial angle rounded, posterior half attenuate; setae dark yellow, apical macrosetae dark brown; dorsal view ( Fig. 56) posteromedial lobe moderately large, gonocoxal bridge absent; lateral view ( Fig. 79) basal half oval, posterior half attenuate; ventral lobe ( Fig. 33) with spines ventrally. Gonostylus ( Fig. 102), basodorsal lobe large, curved anteriorly; ventral margin rounded, setae dark yellow, extending apically in distinct tuft; fine, short spines absent laterally. Aedeagus with dorsal apodeme ( Fig. 125) broad, rectangular, posterolateral margin rounded; ventral apodeme ( Fig. 148) tapered anteriorly, not extending to anterior margin of dorsal apodeme; distiphallus dorsal view ( Fig. 125) tapered apically, lateral view ( Fig. 171) tapered apically in broad curved, apicolateral spines numerous; ejaculatory apodeme ( Fig. 125), anterior margin rounded.

Variation (n=10). Body length 5.2–6.0, 5.6 mm.

Thorax. Macrosetae 3–4 np, 2 sa, 1 pa, 2 dc, 2 sc. Legs. Anteroventral macrosetae 0:0:3–4; pv 0:0:3–7.

Female

Similar to male except as follows.

Variation (n=10).

Body length 5.4–7.2, 6.1 mm.

Head. Antenna dark brown, occasionally with base of flagellum dark yellow. Frons dark brownish gray, ventral third silver with dark brown area dorsolaterally (shape of area varies from distinct circle to broad band which extend across frons when specimen is rotated); setae dark brown, short on brownish gray area of frons. Parafacial reddish brown (occasionally glossy), pruinescence silver dorsally. Maxillary palpus dark yellow, apical fourth dark reddish brown; setae dark yellow to pale reddish brown.

Thorax. Macrosetae 3 np, 2 sa, 1 pa, 2 dc, 2 sc. Legs. Anteroventral macrosetae 0:0:2–6, pv 0:0:2–7.

Abdomen. Dark reddish brown, pruinescence white; tergites 2–7 with posterior margin narrow dark yellow or yellowish orange, tergite 2–6 with posterolateral area of white priunescence; dorsal setae dark reddish brown on dark reddish brown areas and white appressed across posterior margin of tergites 1–3; lateral setae dark reddish brown. Terminalia (MEI 138880). Furca ( Fig. 192) oval; length 0.40 mm, width 0.22 mm; anterolateral projection short. Common duct ( Fig. 192) shorter than furca. Spermathecal duct ( Fig. 192) diverging anteriorly, broad basally with bulbous expansion.

Distribution Brachylinga concava is known from Costa Rica and Panama ( Fig. 214).

Habitats and phenology

Brachylinga concava has been primarily collected in Malaise traps from October to April.

Specimens examined

Type specimen. The holotype male of Brachylinga concava Webb (MEI 007482) is labeled "COSTA RICA, Guanacaste Province, 10 km W San Miguel, 22 February 1991, DWWebb/MEIrwin, Malaise trap" and is deposited in the INHS. PARATYPES: COSTA RICA. GUANACASTE. 10 km W San Miguel [10.4, ­85.04], 21.II.1991, Webb , D. W., ME I, 2♂ MEI 007455, 007626 ( INHS) , Malaise trap; 22.II.1991, 1♂ MEI 007498 ( MEIC) ; 23.II.1991, 6♂ MEI 007475, 007480, 007483, 007492, 007495, 011349 ( INHS) ; 26.II.1991, FDP, 1♂ MEI 047536 ( EMUS) ; 27.II.1991, 2♂ MEI 047559, 047582 ( EMUS) ; 1.III.1991, 1♂ MEI 047620 ( EMUS) ; 5.III.1991, 1♂ MEI 047647 ( EMUS) ; 12.III.1991, 2♂ MEI 047657, 047664 ( MEIC) ; 14–17.III.1991, 1♂ MEI 047672 ( USNM) ; 21–22.III.1991, 1♂ MEI 047733 ( EMUS) ; 25–27.III.1991, 1♂ MEI 047754 ( EMUS) ; 2.IV.1991, 1♂ MEI 047691 ( EMUS) ; 7.IV.1991, 1♂ MEI 047696 ( EMUS) ; 14 km S Cañas [10.304, ­85.1] , 23.III.1989, FDP, 1♂ MEI 072902 ( EMUS) ; 15–24.II.1990, 2♂ MEI 007868–9 ( EMUS) ; 19–28.II.1990, 2♂ MEI 036986, 036990 ( EMUS) ; 23–28.II.1990, 3♂ MEI 007842, 007851, 036988 ( EMUS) ; 1–7.III.1990, 7♂ MEI 072882, 072889, 072925, 072930, 072933, 072948, 072951 ( EMUS) ; 8–15.III.1990, 3♂ MEI 072891, 072897, 072899 ( EMUS) ; 9–14.III.1990, 1♂ MEI 036989 ( EMUS) ; 13–21.III.1990, 1♂ MEI 072884 ( EMUS) ; 13–21.III.1990, 1♀ MEI 072913 ( EMUS) ; 15–22.III.1990, 6♂ MEI 007871–2, 036984–5, 036987, 141793 ( EMUS) ; 16–31.III.1990, 2♂ MEI 072952, 072957 ( EMUS) ; 8 km SW Cuajiniquil, Estación Murciélago [10.849, ­85.781], 100 m , 7–25.III.1994, Quesada , F., 3♂ INB 758713–5, 758724–6, 1♀ INB 758717 ( INBC) ; Bijagual [9.718, ­84.568], 22.II.1991, Webb , D. W., MEI, 1♂ MEI 110417 ( INHS) ; E stancia Santa Rosa [10.84, ­85.62], 300 m, 23.II–8.III.1995, Navarro , E., 1♂ INB 140760 ( INBC) ; 26.II–7.III.1995, Fletes , E., 1♂ INB 200968 ( INBC) ; Peninsula de Nicoya, 8 km SW Cuajiniquil, Estancia Murcielago [10.9, ­85.73], 100 m , 6–24.I.1994, Quesada , F., 1♀ INB 959252 ( INBC) ; S Cañas [10.43, ­85.1] , 22–24.II.1989, FDP, 1♂ MEI 007838 (E MUS) ; S Cañas, Cañas Experiment Station [10.43, ­85.1] , 8–18.III.1988, FDP, 1♂ MEI 007825 ( EMUS) ; La Taboga For. Res., 9 km SW Cañas [10.373, ­85.157] , 17–27.II.1987, Rubink , W. L., 1♂ MEI 007827 ( EMUS) , Malaise trap; Palo Verde National Park, 34 km. SW. Cañas [10.214, ­85.316] , 2.II.1984, Cameron , S. A., 1♂ MEI 084505 ( SEMC) , Malaise trap; Parque Nacional Guanacaste, 30 km N Liberia, Finca Jenny [10.87, ­85.57] , –. II.1992, Espinoza , R., 1♂ INB 799692 ( INBC) ; –. III.1991, 1♀ INB 1326106 ( INBC) ; –. IV.1991, 6♂ INB 481427, 481436, 692670–1, 692677, 692695, 11♀ 1692663, 326099, 326108, 692626–7, 692675–6, 692678, 692693, 692697, 692713 ( INBC) ; Refugio Nacional de Fauna Silvestre Rafael Lucas Rodriguez, Palo Verde [10.35, ­85.35], 10 m , –. III.1991, Acevedo , D., 1♂ INB 592202 ( INBC) ; Santa Rosa National Park , 300 m , –. IV.1984, Janzen, D. H., Hallwachs , W., 1♂ MEI 048125 ( AMNH) ; 18.X–8.XI.1986, Janzen, D., Gauld , I., 1♂ MEI 138788, 14♀ 138773–7, 138780–1, 138784, 138792–3, 138798, 138804, 138807, 138821 ( LACM) , Malaise trap, shaded; 21.II–14.III.1987, 4♂ MEI 138824–5, 138897, 138973, 32♀ 138808 ( INHS) , 138814 (INHS), 138832 (MEIC), 138834 (MEIC), 138837 (USNM), 138840–1, 138843, 138845–6, 138848, 138850–3, 138855–8, 138860, 138862–4, 138879–80, 138884, 138888–91, 138894–5 ( LACM), Malaise trap, shaded ; 21.II–14.III.1987, 9♂ MEI 122209–15, 110363, 110366 ( LACM) , Malaise trap; 14.III–4.IV.1987, 2♂ MEI 139007, 139009, 1♀ 138811 ( LACM) , Malaise trap, shaded; Estancia Santa Rosa [10.84, ­85.62], 300 m , 23.II–7.III.1995, Alvarado , F., 3♂ INB 140046, 140053, 140056 ( INBC) . PANAMA. Isthmus of Panama, Paraiso, Canal Zone [9.035, ­79.629] , 29.XII.1987, MacDonald, Schiefer , 1♂ MEI 030497 ( MEM) .