Boreantrops durango, 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 : 317-318

Boreantrops durango sp. nov.

( Figs. 41, 42 , 68, 108)

Diagnosis. Separable from other members of the mexicanus subgroup by the following combination of characters: Leg joints narrowly orange. Mid tibia with 1 anterodorsal bristle. Mesoscutum strongly sculptured. Male sternite 5 bell-shaped, with a notch in posterior margin. Male distiphallus with dorsal tube narrow at tip.

Description. Head orange, occiput black with reddish brown around posterior margin of eye, frons dark reddish brown on posterior two-thirds. Prementum dark brown with ventral margin orange, maxillary palp yellow. Mostly covered with microtomentum, frons with microtomentum medially reaching from postocellar bristles anteriorly through ocellar triangle to anterior margin of frons, microtomentum on orbital plates reaching bases of interfrontal setae, bare in a small patch just anterior to vertical bristles, face with patch of microtomentum below antenna reaching ventrally to level of U-shaped mark. Ocellar bristles at level of anterior margin of median ocellus. Subvibrissal bristle and anterior genal bristles about 0.5X length of vibrissa.

Thorax black, mostly covered with microtomentum. Proepisternum shiny, anepisternum with microtomentum along dorsal third and posterior third and in a thin line along anterior margin below spiracle, katepisternum with a shiny spot behind fore coxa, meron shiny, metapleuron shiny with a stripe of microtomentum between posterior spiracle and hind coxa. Mesoscutum sculptured. Halter white, brownish below knob.

Legs black, joints and trochanters yellow to brown, fore and hind tarsi with 2 basal tarsomeres ivory white and 3 distal tarsomeres brown, mid tarsus with 2 basal tarsomeres ivory white and 3 distal tarsomeres brown. Mid tibia with 1 anteroventral, 1 posteroventral, 6 subapical bristles. Hind tibia with 1 ventroapical bristle.

Wing brown, veins dark brown, crossveins r-m and dm-cu white, vein R4+5 with 2 pale spots distal to crossvein r-m.

Abdominal syntergite 1+2 heavily sclerotized with a semicircular weakly sclerotized patch anteriorly, black, covered with microtomentum. Tergites 3–4 heavily sclerotized with irregular, weakly sclerotized margin, tergite 5 weakly sclerotized. Sternites weakly sclerotized.

Male postabdomen: Sternite 5 longer than width at middle, narrow anteriorly, strongly flared posteriorly, posterior margin broadly notched with an interrupted row of setae, anterior apodeme broad, about as long as external portion, without keel ( Fig. 42 ). Surstylus paddle-shaped. Hypandrial arms with ventral tab-like structures. Pregonite small, discrete. Postgonite with lobes widely separated, anterior lobe broad, rounded, posterior lobe longer, narrow, pointed. Basiphallus with long epiphallus, broad, transparent preepiphallus. Distiphallus with strongly curved spinose dorsal tube, distal portion moderate length, flattened dorsally ( Fig. 41 ).

Female postabdomen: Tergites 6–7 with anterior and lateral margins heavily sclerotized, center and posterior margin not sclerotized. Tergite 8 covered with microtomentum, except anterior margin. Epiproct without anterior arms, mostly covered with microtomentum except anterior corners, with 2 setae. Cerci broad. Sternites 6–7 with margins heavily sclerotized, center not sclerotized. Sclerites of sternite 8 broadest posteriorly, posterior half covered with microtomentum. Hypoproct lozenge-shaped, covered with microtomentum. Spermathecae about 2.5X longer than wide, annulated, apex invaginated, sclerotized duct slightly shorter than bulb (Fig. 68).

Type material. Holotype ♂: MEXICO: Durango : El Salto, 13 mi W, 9000′, 18 Jun 1964, J.F. McAlpine, debu01155353 ( CNCI). Paratypes: same data as holotype (1 ♂, 5♀, CNCI); El Salto, 13 mi E, 9000′, 18 Jun 1964, J.F. McAlpine (1 ♂, CNCI); Sinaloa: Portrerillos, 15 mi W El Palmito, 5000′, 16 Jul 1964, J.F. McAlpine (1 ♂, CNCI).

Distribution. Northwestern Mexico (Fig. 108).

Etymology. The species name is an arbitrary combination of letters derived from the type locality.

Comments. The females described here are somewhat tentatively associated. B. longiphallus occurs nearby, but no males were collected at the type locality of B. durango and confidently associated females of B. longiphallus have distinct spermathecae.

Figures

FIGURES 37 – 42. Boreantrops male terminalia. B. avignis: 37) phallus, postgonite, and phallapodeme, lateral view, 38) sternite 5; B. costaricensis: 39) phallus, postgonite, and phallapodeme, lateral view, 40) sternite 5; B. durango: 41) phallus, postgonite, and phallapodeme, lateral view, 42) sternite 5.