New genera of philopotine spider flies (Diptera, Acroceridae) with a key to living and fossil genera Author Gillung, Jessica P. Author Winterton, Shaun L. text ZooKeys 2011 127 15 27 http://dx.doi.org/10.3897/zookeys.127.1824 journal article http://dx.doi.org/10.3897/zookeys.127.1824 1313-2970-127-15 Quasi gen. n. Figs 1 A-C 35 Type species. Quasi fisheri sp. n. Diagnosis. Body shape arched; colouration non-metallic pale brown; head width slightly smaller than thorax width; shape hemispherical; postocular ridge and occiput rounded ; posterior margin of eye rounded; eyes bare; three ocelli present, medial ocellus slightly smaller; position of antennae on head nearer to mouthparts; eyes contiguous above antennal base, not contiguous below; palpi absent; proboscis much shorter than head length; flagellum shape stylate, apex with terminal seta; thorax with postpronotal lobes enlarged, medially contiguous to form collar; subscutellum not enlarged, barely visible; legs with tibial spines absent; pulvilli present; legs not greatly elongated; wing hyaline, markings absent; costa ending in radial field; costal margin straight; humeral crossvein absent; radial veins meeting wing margin before wing apex; R1 slightly inflated distally at pterostigma; R2+3 present, reaching wing margin; R4+5 present as very short , single vein, not reaching wing margin; medial vein compliment with only one M vein present; discal cell absent; medial vein very short, not reaching wing margin; cell m3 absent; crossvein 2r-m absent; Cu reduced, not reaching wing margin; anal lobe not enlarged; alula well developed; abdomen smooth, shape rounded, cylindrical, similar width to thorax. Etymology. Derived from Latin quasi, appearing as if resembling; referring to the likeness of this species to members of Terphis . Comments. This genus is represented by only a single species Quasi fisheri sp. n. from Veracruz, Mexico. It is closely related to Terphis and Philopota based on reduction in wing veins. The position of the antennae, proximate to the reduced mouthparts, reduced wing venation and absence of abdominal tubercles readily differentiates this genus from all other philopotine genera. Figure 3. Quasi fisheri gen. et sp. n., male, anterolateral view [Morphbank: 693076]. Body length = 6.0 mm. Figure 4. Quasi fisheri gen. et sp. n., male, dorsal view [Morphbank: 693077]. Body length = 6.0 mm. Figure 5. Quasi fisheri gen. et sp. n., male, anterior view [Morphbank: 693078]. Body length = 6.0 mm.