Chamaepsila setalba
elongate 1st flagellomere and white arista
Key: Freidberg and Shatalkin, 2008
Distribution
Europe: Countries (published), online at Fauna Europaea, Occurrences at GBIF
Freidberg and Shatalkin, 2008
Diagnosis This species was described as Chyliza gracilis Loew and is transferred to Chamaepsila and renamed by us here (see Comments below). It is only known from the original description but nevertheless is one of the most easily characterized species (or species complex) of Chamaepsila, differing from all congeners by the elongate 1st flagellomere and the white arista. Taking into account all characters Ch. setalba occupies a isolated position within Chamaepsila. According to Hennig (1941), the type is probably lost. A female, collected more recently (BULGARIA: Sandanski, 4.x.1973, Gorodkov; ZMAS), is very similar to specimens we consider to be Ch. setalba (see Material examined, below), differing by the presence of poc and by having two pairs of scutellar setae (usually one pair in Ch. setalba), a narrower occipital spot, and m vt placed on the yellow part (placed on the border of the occipital spot in Ch. setalba). This female may represent an undescribed species.
Redescription
Male. Head (Fig. 3) predominantly yellow; ocellar triangle black; occiput with large lateral black spot posterior to eye, m vt placed at border of spot; eye in profile attain- ing anterior margin of face; scape and pedicel yellow to brown; 1st
flagellomere dark brown to black, slightly paler at base, about 3–4 times as long as wide, slightly concave dorsally and slightly convex ventrally; arista about as long as head height, white, with dense white rays, feathering about 0.75 times as wide as 1st flagellomere; frons length equal to frons width; eye round; gena anteriorly about 0.1 and posteriorly about 0.33 times as high as eye; palpus mostly yellow, brownish in apical half. Thorax predomi-nantly yellow to brownish; postpronotum and adjacent part of mesonotum up to level of mesonotal stripe, anepisternum dorsally, notopleuron, anepimeron (entirely), and laterotergite black or blackish, although some parts sometimes lighter; mesonotum with blackish postsutural stripe slightly lateral to dc seta; scutellum yellow, usually with one (apical) pair of setae. In one specimen basal seta present on one side. Legs yellow. Wing hyaline. Ratio of distalmost sections of vein M (from apex) 2.2: 2.2: 1.0. Halter yellow. Abdomen black. Terminalia (Fig. 4): parameres slightly shifted in direction of basis of phallapodeme; whereas parameres of the majority of Chamaepsila species situated on tips of fork of phallapodeme. Chaetotaxy: 2 vt, poc absent, 2 orb, 1 npl, 1 psut spal (sa), 1 pal, 1 dc, 1 sc (a setula-like second seta on one side of scutellum in one specimen); anepisternal tuft of white setulae moderately developed.
Body length 3.8–4.7 mm; wing length 3.8–5.0 mm
Female. Similar to male. Ovipositor unsclerotized. Body length 3.5–5.0 mm; wing length 3.6–5.0 mm