Planinasus electrus Grimaldi & Mathis

Mathis, Wayne N., Rung, Alessandra & Kotrba, Marion, 2012, A revision of the genus Planinasus Cresson (Diptera, Periscelididae), ZooKeys 225, pp. 1-83 : 66-68

19. Planinasus electrus Grimaldi & Mathis

Planinasus electrus Grimaldi and Mathis 1993: 396. Fossil; Dominican Republic. HT ♀ AMNH [AMNH type number DR-8-208; specific provenance unknown; size of amber 1.1 X 1.3 cm, nearly flat]. Evenhuis 1994: 424 [review]. Mathis and Rung 2011: 363 [world catalog].

Description of female.

Moderately small flies, body length 2.20 mm; wing length 1.71 mm.

Head: Width 0.78 mm; facial width at narrowest point 0.25 mm; frons dark brown, glabrous; interfrontal seta short, about half length of lateral vertical seta, reclinate, separated by slightly more than distance between outside margins of posterior ocelli; postocellar seta lacking; proclintate and reclinate fronto-orbital setae approximately equal in length, reclinate seta inserted slightly medial to proclinate seta, separated from latter by about 3 times its diameter at base; medial and lateral vertical setae about equal in length. Antenna bicolored, scape and pedicel brown, basal flagellomere pale, mostly whitish yellow with pale brown area immediately around base of arista; scape very thin; antennal bases separated by about diameter of pedicel; pedicel with deep anterior cleft; ventral projection of pedicel short, not extended anteriorly much beyond dorsal margin; medial half of pedicel with 2 black, stout setae of equal length, both oriented anteriad, parallel; lateral half of pedicel with thin seta dorsally, near cleft, and 4-5 fine, smaller setulae in row on anterolateral margin; flagellomere short, width about 2/3 length; arista with lateral trunk bearing 4 branches all on one side; apical branch pair smallest; main ramus of arista with 4 large dorsal branches, plus terminal fork; 4 smaller medial branches; 2 ventral branches; both rami of arista with a common base, but no common ramus. Face bicolored, mostly pale, whitish yellow, but with oral margin and narrow medial extension brown; facial setae in 2 irregular rows; setae along ventral row of larger medial setae in row along sloping line at transition between pale and brown color. 2 other facial setae inserted dorsad of longer row, between large dorsoclinate setae and anteroventral margin of eye (seta inserted closer to eye almost twice length of seta inserted between it and dorsoclinate setae). Proboscis pale; palpus thin, pale.

Thorax: Length 0.74 mm; mesonotum and pleuron dark brown; anterior dorsocentral seta about midway between anterior margin of notum and noto-scutellar suture; posterior dorsocentral seta inserted closer to scutellum than to anterior dorsocentral seta; acrostichal setulae minute, barely discernible; katepisternum with 1 larger seta, 3-4 much small setae; anepisternum with row of about 4 fine setulae along posterior margin. Legs: coxae and femora brown; tibiae mostly brown, apical 1/4-1/5 pale; length of basitarsomeres about equal to length of all 4 distal tarsomeres; tarsomeres 1-4 pale; apical tarsomeres brown; midtibia bearing several small setae (length about ½ that of tibia width); 1 ventroapical, 1 preapical lateral, and pair of dorsoapical. Halter pale. Wing: Length 1.71 mm; hyaline; vein R1 thickened at merger with C; Sc very short, incomplete; subcostal break present, but not well defined; vein R2+3 extended to about apical 1/3 of R4+5; veins R4+5 and M parallel; apices of veins CuA1 and A1 tapered, not extended to wing margin cells cup, bm, and dm complete.

Abdomen: Relatively flat dorsoventrally; tapered apically. Tergites, epiproct, and hypoproct uniformly brown.

Type material.

The holotype female is preserved in Dominican amber (Dominican Republic. specific provenance unknown) and is deposited in the AMNH (type number DR-8-208).