Apiochaeta Czerny, 1903

Lonsdale, Owen & Marshall, Stephen A., 2008, Revision of the temperate South American genus Apiochaeta Czerny, 1903, with synonymy of Alloclusia Hendel, 1917 (Diptera: Clusiidae), Zootaxa 1944 (1), pp. 1-33 : 8-9

Apiochaeta Czerny, 1903

Heterochroa Schiner, 1868: 236 . Type species, Heterochroa picta Schiner , by original designation (= philippii Rondani ). A junior homonym of Heterochroa Boisduval, 1836 (Nymphalidae) .

Apiochaeta Czerny, 1903: 98 . Type species, Heterochroa bicolor Schiner , subsequent designation ( Soós 1968: 2). Melander & Argo 1924: 6; Malloch 1933: 238; Stuardo Ortiz 1946: 150.

Alloclusia Hendel, 1917: 36 . Type species, Peratochetvs philippii Rondani , by original designation. Melander & Argo 1924: 32; Malloch 1933: 238; Stuardo Ortiz 1946: 149. Syn. nov.

Diagnosis. Three dorsocentral bristles (evenly-spaced in all species except A. connexa ). Three or four frontoorbital bristles (anterior bristle inclinate, remainder reclinate); frons covered with minute black setulae. Mid tibia with dorsal preapical bristle. Subnotal stripe present. M 1+2 ratio less than 2.5 (3.1 in A. bicolor ). Vein dmcu oblique. Basiphallus with curled joint articulating with base of distiphallus. Two or three hypandrial bristles present. Distiphallus with one pair of long basal spinulose projections. Ventral receptacle slightly flattened dorsoventrally and recurved ventrally, with numerous transverse wrinkles and one pair of ventral longitudinal grooves.

Generic description:

General. Length 3.0–7.8mm. Body slender, colour yellow with brown to black pattern; scutum almost always bivittate and pleuron almost always with subnotal stripe; face usually brown to black. Tergite 1 and female terminalia yellow to white with remainder of abdomen variously patterned. Angular extensions on outer and inner margins of pedicel acute. Arista black with base white; sparsely plumose to pubescent. Lateral margins of frons parallel; minutely pilose and with scattered black setulae. Gena and parafacial shiny to vari- ously pilose. M 1+2 ratio 1.1–3.1. Vein dm-cu oblique. Wing usually infuscated along apex and around crossveins.

Chaetotaxy. Bristles brown to black. Anterior two fronto-orbital bristles close to each other on anterior margin of frons and posterior bristle on posteromedial margin; sometimes small additional reclinate bristle present. Ocellar and postvertical bristles divergent and usually strong. Three pairs of dorsocentral bristles (evenly-spaced in all species except A. connexa ). One pair of strong prescutellar acrostichal bristles. Scutellum with one or two pairs of lateral bristles and one pair of cruciate apical bristles. Mid tibia with dorsal preapical bristle. Venter of male fore and mid femora with one anterior row and two posterior rows of strong closely spaced bristles (first posterior row shorter than second).

Male abdomen. Tergites 1 and 2 fused; sternite 1 reduced to thin, weakly sclerotized band; tergites 3–6 and sternites 2–5 complete. Abdomen encircled by “annulus” comprised of fused sternites 6–8 and tergite 7 (homology of this latter sclerite uncertain – possibly derived from right margin of sternite 8); sternite 8 dorsal and setose; sternite 7 on left side between sternites 6 and 8 and heavily sclerotized anteriorly; sternite 6 fused to sternite 7 along dorsal margin, attached to sternite 8 ventrally by weakly sclerotized section and heavily sclerotized anteriorly; tergite 7 sometimes present (large and distinct or small and inseparable from margin of sternite 8). Spiracles in membrane ventral to tergites 1–5, dorsolaterally between sternites 6 and 7, and ventrally between sternites 6 and 8. Epandrium dome-shaped and at least as wide as preabdomen. Surstylus at least 4/5 length of epandrium with numerous short, stout bristles on inner face. Cerci fused, small, setulose, lobate, slightly projecting and medially emarginate. Hypandrial arm elongate; ventrolateral lobe well-developed with two strong medial bristles and sometimes one minute distal bristle. Phallapodeme well developed. Pregonite ovate to rectangular and with several bristles. Postgonite lobate with several distal setulae. Basiphallus “C” shaped with curled distal joint articulating with distiphallus. Epiphallus small and fin-like. Distiphallus elongate, strongly bent, weakly sclerotized medially, and basally fused to one pair of elongate spinulose lateral lobes.

Female abdomen. Tergites 1 and 2 fused; sternite 1 reduced to thin, weakly sclerotized strip; tergites 3 to 6 and sternites 2 to 6 complete. Segments 7 and 8 narrowed into long, thin tube; segments separated by long membranous area, sometimes equaling segment length; segment 7 large, strongly sclerotized, and with thin dorsomedial desclerotization; terminal segments often deeply telescoped. Sternite 8 bifid, at least on distal fourth, and divided lengthwise by weakly sclerotized line. Cercus thin and approximately 3/4 length of sternite 8. Spiracles in membrane below tergites on segments 1 to 7. One pair of weakly sclerotized, unpigmented, spherical and smooth-surfaced spermathecae. Spermathecal ducts thin and weakly sclerotized. Ventral receptacle slightly flattened dorsoventrally and recurved ventrally, with numerous transverse wrinkles and one pair of ventral longitudinal grooves.