Stylospania Frey, 1954

Kerr, Peter H., 2010, 2592, Zootaxa 2592, pp. 1-133 : 80

Genus Stylospania Frey

Figure 23, 83, 103.

Stylospania Frey 1954: 23 . Type species Stylospania lancifera Frey 1954 , by monotypy.

Diagnosis. This genus is based on a single male specimen collected from Samar, Catbalogan, Philippines. Stylospania lancifera bears most features found in Chrysopilus , but may be distinguished from this genus by its stylate flagellum. It has a reduced, bare proepimeron and its genitalia are indistinguishable from those of males of many Chrysopilus species. The only known specimen of Stylospania lancifera is devoid of thoracic setae. The female is unknown.

Stylospania lancifera is a delicate fly, fairly small in size (appx. 4.5 mm), with long, thin legs; orangebrown. Wings are hyaline, without markings; male dichoptic; flagellum subcircular with long, tapering stylus; mandibles absent; laterotergite setose; M 3 present; tibial spur formula 0:2:1; hind tibia with short macrochaetae; tergite 9 without ventrolateral arms. Stylospania lancifera is known to occur only in the Philippines. Stylospania may be distinguished from all Chrysopilus by its antenna, which has a stylate flagellum. Also, the Stylospania males are dichoptic, which is a relatively rare condition for Chrysopilus .

Description. Head. Clypeus bulbous. Scape approximately same size as pedicel. First flagellomere laterally compressed. First flagellomere of antenna enlarged bearing stylus of single segment, stylus narrow, nearly arista-like. Eyes inconspicuously setulose; male dichoptic; ommatidia evenly distributed, of equal size; not flattened dorsally. Head wider than thorax. Labella with pseudotracheae, longer than palpus. Theca short. Palpus one-segmented. Mandibles absent.

Thorax. Mesonotum without vittae. Setae of dorsum all of equal length. Specimen lacks metallic- or scale-like thoracic setae, although these are likely present. Proepimeron reduced, bare. Anepisternum bare. Laterotergite setose throughout, katatergite and anatergite indistinguishable. Thoracic surface between base of halter and postspiracular sclerite without setulae. Thoracic spiracle without flaps, nor with setulae. Postspiracular scale absent. Postspiracular sclerite without setulae. Thoracic surface immediately posterior to postspiracular sclerite bare. Proscutellum absent. Subscutellum inconspicuous, not enlarged. Wing hyaline, without markings. Wing with pterostigma. Lower calypter reduced. Upper calypter well developed, full and rounded, with broad curvature, lobe-like, width twice length or less. Alula broad, rounded evenly. Anal lobe well developed. Sc-r crossvein weakly developed, positioned distal to h by approximate length of h. Dorsal side of R 1 setulose, ventral side bare. R 1 and R 2+3 close together at wing margin (R 2+3 clearly closer to R 1 than to R 4). R 2+3 directed toward wing margin, meeting margin abruptly. R 2+3 bare on both dorsal and ventral surfaces of wing membrane. Base of R 4 –R 5 fork proximal or directly above distal end of cell dm. R 4 at base strongly curved or angled, straight or nearly straight apically. R 4 and R 5 contain wing tip. R 5 aligned with R 4+5. M 3 reaches wing margin. Tibial spur formula 0:2:1. Hind coxal tubercle present. Hind tibial macrochaetae present; small, easily overlooked, nearly flush with sclerite surface. Hind tibia without ventro-apical swelling. First hind metatarsus of male not swollen.

Abdomen. Abdominal segments evenly tapered. Epandrium wider than long, modestly curved anteriorly. Epandrium simple, not containing hypandrium ventrally. Tergite 10 absent. Hypoproct rectangular; wider than long; tomentose, without setae. Cerci partially displaced from one another, separation distance approximately half width of single cercus. Hypandrium fused entirely to gonocoxites. Gonocoxite smooth dorsally, without sinuous ridge leading to gonocoxal apodeme. Gonocoxal apodemes long enough to reach anterior margin of hypandrium. Sperm sac developed into bulbous sac ventrally, without distinct lobes. Lateral ejaculatory processes present, part of sperm sac posteriorly, arising free of sperm sac membrane dorsally. Ejaculatory apodeme moderately long, reaching anterior margin of hypandrium, laterally compressed. Aedeagal tines absent. Endoaedeagal process absent. Gonostylus heavily setose.

Larva. Unknown.

Biology. Unknown.

Literature. In addition to the original literature ( Frey 1954), Nagatomi (1982a) provides a brief Diagnosis of this genus.