Boreantrops auranticeps, Kits, Joel H. & Marshall, Stephen A., 2015

Kits, Joel H. & Marshall, Stephen A., 2015, A revision of Boreantrops Kits & Marshall (Diptera: Sphaeroceridae: Archiborborinae), Zootaxa 3915 (3), pp. 301-355 : 334-336

Boreantrops auranticeps sp. nov.

( Figs. 4 , 17, 78, 79, 80, 121)

Diagnosis. Separable from other members of the emarginatus group by the following characters: Occiput and prementum orange. Fore leg with brown tarsomeres. Mid tibia with row of anterodorsal bristles. Hind tibia with two ventroapical bristles. Wing with spots restricted to crossveins and distal part of vein R4+5; vein R2+3 strongly contorted.

Description. Head orange ( Fig. 4 ), occiput with a black U-shaped mark around foramen. Maxillary palp yellow. Occiput and gena covered with microtomentum, frons with microtomentum on orbital plate in a line medial to inner vertical and around bases of orbital bristles to bases of interfrontal setae and between ocelli to bases of ocellar bristles, face with microtomentum below lunule and in dense crescent below antenna. Ocellar bristles at level of anterior margin of median ocellus. Subvibrissal and anterior genal bristle about 0.5X length of vibrissa.

Thorax black, mostly covered with microtomentum. Proepisternum shiny, anepisternum mostly shiny with microtomentum covering dorsal quarter and posterior third, katepisternum with a shiny spot behind fore coxa, meron and metapleuron shiny with band of microtomentum between posterior spiracle and hind coxa. Halter white, brownish below knob.

Legs black, joints and fore tarsus dark brown, trochanters and mid and hind tarsi yellow. Mid tibia with 1 anterodorsal at two-thirds, 1 anteroventral, 1 posteroventral, 6 subapical bristles. Hind tibia with 2 ventroapical bristles.

Wing brown, veins dark brown. White spots on crossveins r-m, bm-cu, dm-cu, vein R4+5 with 2 white spots distal to crossvein r-m. Vein R2+3 recurved, joining costa at nearly right angle (Fig. 17).

Abdomen with tergites and sternites weakly sclerotized. Syntergite 1+2 with posterolateral corners and a thin band between them strongly sclerotized, tergites 3–4 with a thin posterior band moderately sclerotized.

Male postabdomen: Sternite 5 with lateral margins strongly rounded, posterolateral corners folded over dorsally, posterior margin broadly but shallowly notched, anterior apodeme slightly longer than medial length of external portion, without keel ( Fig. 79 ). Epandrium fused between anal opening and cerci. Surstylus with broad anterior projection, ventral portion broad, posterior margin with long, thick setae ventrally ( Fig. 80 ). Pregonite not fused with postgonite, fairly large. Postgonite narrow, lobes narrowly separated, anterior lobe thin, angled relative to broad posterior lobe. Basiphallus with long, broad-based epiphallus, preepiphallus narrow, pointed. Distiphallus with strongly curved, spinose dorsal tube, flanked by one spike-like sclerite, distally with a second projecting spike-like sclerite ( Fig. 78 ).

Female postabdomen: Tergites 6–7 and sternites 6–7 very wide, crescent-shaped; tergite 6 sclerotized along anterior margin, tergite 7 mostly sclerotized, with two large unsclerotized spots medially, sternites sclerotized along margins, not sclerotized medially. Tergites with 3 posterior strips, sternites with 2 posterior strips. Tergite 8 very wide anteriorly, narrower posteriorly, posterior half covered with microtomentum. Epiproct with barely separated anterior arms, 1 pair of setae, some microtomentum medially. Cerci long, narrow. Sternite 8 with anterior, weakly connected patch sculptured with ridges, posterior portion with posterior half covered with microtomentum. Hypoproct with 3 anterior patches and posterior margin moderately sclerotized. Spermathecae sausage-shaped, about 5X longer than wide, with shallow apical invagination.

Type material. Holotype ♂: ECUADOR: Napo: SierrAzul Res., 14 km W Cosanga, 0°40'55"S 77°56'69"W, 2200 m, dung baits, 8–11 May 2002, M. Buck, debu00202307 ( QCAZ). Paratypes: same data as holotype (1 ♂, 6 ♀, DEBU, QCAZ); as above but S.M. Paiero (1 ♂, DEBU); as above but on dung, 9–10 May 2002, M. Buck (1 ♂, DEBU); Pichincha: Bellavista Reserve, 2200 m, 30 Oct 1999, S.A. Marshall (2 ♀, DEBU, QCAZ); as above but 9–13 May 2009 (1 ♀, DEBU); as above but 1 May 2011 (1 ♂, 1 ♀, DEBU, QCAZ).

Distribution. Northern Ecuador (Fig. 121). Elevations around 2200 m.

Etymology. The species name refers to the striking orange head in this species.

Comments. One dissected female contained about 27 fairly small eggs.

Figures

FIGURES 1 – 4. Boreantrops, images of living flies. 1) B. inbio, San Gerardo de Dota, San José, Costa Rica; 2) B. albipes, San Gerardo Biological Station, Alajuela, Costa Rica; 3) B. wayqecha, Wayqecha Biological Station, Cusco, Peru; 4) B. auranticeps, Bellavista Cloud Forest Reserve, Pichincha, Ecuador. 1, 3, and 4 by SAM, 2 by Morgan Jackson, used with permission.

FIGURES 78 – 85. Boreantrops male terminalia. B. auranticeps: 78) phallus, postgonite, and phallapodeme, lateral view, 79) sternite 5, 80) right surstylus, interior view; B. boliviensis: 81) phallus, postgonite, and phallapodeme, lateral view; B. challabamba: 82) phallus, postgonite, and phallapodeme, lateral view, 83) right surstylus, interior view; B. emarginatus: 84) phallus, postgonite, and phallapodeme, lateral view, 85) sternite 5. prj: projection of the postgonite.