Boreantrops pollex, 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 : 341-342

Boreantrops pollex sp. nov.

( Figs. 89, 90, 91 , 126)

Diagnosis. Separable from other members of the emarginatus group by the following characters: Occiput black, prementum yellow. Anterior margin of anepisternum shiny below spiracle. Mid tibia without row of anterodorsal bristles. Hind tibia with one ventroapical bristle. Wing with white spot on vein R4+5 basal to r-m crossvein and at vein tips. Male postgonite without a projection on posterior margin.

Description. Occiput black, frontal triangle and orbital plates reddish brown to dark brown, interfrontal plates orange to reddish brown, face, gena, and antenna orange. Maxillary palp and prementum yellow. Occiput and gena covered with microtomentum, frons mostly shiny with microtomentum on orbital plate in a line medial to inner vertical and around bases of orbital bristles, face with microtomentum below lunule and in dense crescent below antenna. Ocellar bristles just anterior to 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, trochanters and joints dark reddish brown, fore tarsus brown, mid and hind tarsi with 2 basal tarsomeres yellow, 3 distal tarsomeres brown. Mid tibia with 1 anteroventral, 6 subapical bristles. Hind tibia with 1 long thin anteroventral, 1 ventroapical bristle.

Wing brown, veins dark brown. White spots on crossvein r-m, bm-cu, and dm-cu, veins R2+3 and M with spots at apex, vein R4+5 with 1 spot basal to crossvein r-m, 2 distal to crossvein r-m, and 1 at apex. Vein R2+3 slightly recurved (as in Fig. 20).

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, posterior margin broadly but shallowly notched, anterior apodeme slightly longer than external portion, without keel ( Fig. 90 ). Epandrium extending medially above cerci but not fused in middle, anal opening keyhole shaped. Surstylus with anterior thumb-like projection, ventral portion narrow, posterior margin with peg-like setae ventrally ( Fig. 91 ). Pregonite not fused with postgonite, fairly large. Postgonite very narrow, posterior margin straight, lobes not separated, posterior lobe longer. Basiphallus narrow, with long epiphallus, preepiphallus broad, triangular. Distiphallus with a long dorsal tube with spines near base, flanked by two spike-like sclerites, distal sclerite projecting dorsally ( Fig. 89 ).

Female postabdomen: Tergites 6–7 and sternites 6–7 much wider than long, tergite 6 with thin, irregular sclerotization along margins, tergite 7 sclerotized along anterior and lateral margins only, sternite 6 with some irregular sclerotization along anterior margin, sternite 7 sclerotized around margins, medial unsclerotized patch round. Tergite 8 broad, heavily sclerotized, lateral margins rounded, anterior margin with a narrow notch, shallowly emarginated posteriorly, posterior two-thirds covered with microtomentum. Epiproct with fairly long anterior arms, 1 pair of setae, microtomentum medially. Cerci long, narrow. Sclerites of sternite 8 with anterior half shiny and sculptured, posterior half slightly wider, covered with microtomentum. Hypoproct rounded, moderately sclerotized except small, central weakly sclerotized spot. Spermathecae sausage-shaped, about 5X longer than wide, with shallow apical invagination, sclerotized duct about two-thirds as long as bulb.

Type material. Holotype ♂: ECUADOR: Napo: Baeza, 5 Mar 1979, S.A. Marshall, debu01039421 ( QCAZ). Paratypes: same data as holotype (11 ♀, DEBU, QCAZ); Baeza, 7 km S, 2000 m, dung trap, 22 Feb 1979, H. & A. Howden (1 ♂, 3 ♀, USNM); as above but 23 Feb 1979 (4 ♀, USNM); as above but 25 Feb 1979 (12 ♂, 3 ♀, USNM); Cosanga, 3.5 km S, trail above pipeline, 2250 m, sweeping, 6 Nov 1999, S.A. Marshall (1 ♀, DEBU); Cosanga, 4.2 km S, pipeline trail, 2200 m, 7 Nov 1999, S.A. Marshall (1 ♂, 1 ♀, DEBU); El Chaco, 2000 m, Malaise trap, 15–23 Feb 1983, Masner & Sharkey (1 ♂, DEBU); SierrAzul Lodge, 14 km W Cosanga, 2200 m, forest, sweeping, 5 Nov 1999, S.A. Marshall (1 ♀, DEBU); SierrAzul Res., 14 km W Cosanga, 2200 m, 10 May 2002, S.A. Marshall (1 ♀, DEBU); as above but dung baits, 8–11 May 2002, M. Buck (1 ♂, 4 ♀, DEBU, QCAZ); as above but on dung, 9–10 May 2002 (1 ♀, DEBU); Zamora-Chinchipe: San Francisco, Reserva Biológica San Francisco, Atajo trail, 2000 m, yellow pans, 14–18 Feb 2009, M. Pollet & A. De Braekeleer (1 ♂, UTPL); as above but 18–25 Feb 2009 (2 ♂, DEBU, UTPL); San Francisco, Reserva Biológica San Francisco, Canal trail, 2000 m, blue pans, 18–25 Feb 2009, M. Pollet & A. De Braekeleer (1 ♀, UTPL); as above but yellow pans, 17–25 Feb 2009 (1 ♀, UTPL); as above but 25 Feb–3 Mar 2009 (5 ♂, 5 ♀, DEBU, UTPL); San Francisco, Reserva Biológica San Francisco, Río San Francisco trail, 2000 m, yellow pans, 18–25 Feb 2009, M. Pollet & A. De Braekeleer (1 ♀, UTPL); as above but 25 Feb–3 Mar 2009 (3 ♀, DEBU, UTPL).

Distribution. Ecuador, on the eastern slope of the Andes (Fig. 126). Elevations from 2000–2250 m.

Etymology. The species name refers to the thumb-like projection on the surstylus (Latin pollex , thumb). It is a noun in apposition.

Comments. This species is very similar to B. punctipennis but is separable based on the male genitalia. The known ranges of the two species are widely separated, although most of Peru is poorly collected and they may approach more closely than is currently known.

We obtained partial COI sequences from two specimens of each species (sequenced at the Biodiversity Institute of Ontario). The sequences of B. pollex (Genbank accession numbers JX 260384 and JX 260385 , both from SierrAzul Lodge) differed by 0.16%, while those of B. punctipennis (Genbank accession numbers JX 260382 and JX 260383 , from Apa Apa Reserve and 10 km NW Caranavi) differed by 0%. The minimum distance between the species was 2.46% (all distances based on Kimura 2-parameter measure).

Figures

FIGURES 86 – 92. Boreantrops male terminalia. B. machinator: 86) phallus, postgonite, and phallapodeme, lateral view, 87) sternite 5, 88) right surstylus, interior view; B. pollex: 89) phallus, postgonite, and phallapodeme, lateral view, 90) sternite 5, 91) right surstylus, interior view; B. punctipennis: 92) phallus, postgonite, and phallapodeme, lateral view. sls: spike – like sclerites.