Tetrameringia maculata, Sasakawa, Mitsuhiro, 2011

Sasakawa, Mitsuhiro, 2011, Oriental species of clusiid flies (Diptera: Clusiidae: Clusiinae), Zootaxa 3038, pp. 1-28 : 15-16

Tetrameringia maculata sp. nov.

( Figs 23, 24 )

Type material. Holotype male ( BPBM 17246), Laos, Vientiane Prov., Ban Van Eue, 29. IV. 1966, native collector, light trap (Rondon-Bishop collection). Paratypes: 13, 5Ƥ, same data as holotype; 6Ƥ, same locality as holotype, 15–31. V. 1965, 15. V. 1967, and 15. IX. 1967, native collector; Ƥ, same locality as holotype, 29. IV. 1966, native collector, Malaise trap.

Diagnosis. This species is characterized by having two dark spots on the mesoscutum, a largely black anepisternum, three pairs of sc, and an inverted-L-shaped surstylus.

Description. MALE. Head yellow; frons shining, brown-tinged on dorsal half; ocellar triangle brown. Antenna and palpus brownish yellow, first antennal flagellomere brown-tinged surrounding base of black arista. Thorax brownish yellow; mesoscutum weakly shining, with pair of brownish-black, oval spots between dc- and salines (spots 2/3–3/4 as long as distance between transverse and scutoscutellar sutures, extending slightly inside of dc-lines but not extending to sa- and pa-bases); anepisternum posteriorly with shining black spot (this 2/3 as high as and 1/2 as wide as sclerite), anatergite and katatergite brown; scutellum yellow, with pale brown, anterolateral spots before bases of lsc. Wing faintly infuscated on apical 1/3, fading behind M1 or CuA1; calypter with margin and fringe yellowish brown; halter yellow. Legs yellow. Abdomen entirely black, shining (holotype), but in paratype male, T1 and T2 yellowish brown, T3–5 brown and blackened laterally, T6 and S8 black. Bristles on head and thorax brown, those on abdomen black.

Frons as wide as eye, almost parallel-sided; frontalia sparsely setulose on ventral part; ventral part of parafrontalia at level of antennal base slightly projecting above eye in profile; or three, second or shorter than others; oc and poc subequal in length, slightly shorter than second or; eye 1.2 times as high as broad; gena 1/7–1/5 as high as eye; vi 2 /3 as long as ivt: pm six. First antennal flagellomere shorter than broad, with long, whitish pile; arista plumose but more sparsely so on apical 1/3, with longest pubescence about 1/3 as long as width of first flagellomere; palpus slightly wider than genal height, nearly 2/3 as wide as first flagellomere.

Mesoscutum with three dc, first dc slightly longer than acr and 1/3 as long as third dc, second dc 1/2–2/3 as long as third dc and situated behind level of sa; acr in six or seven irregular rows; prs subequal to or shorter than second dc; prsc 1/2 as long as third dc; scutellum with three pairs of sc: dsc nearly twice as long as lsc, asc twice as long as dsc. Wing 2.9–3.0 (3.0) mm long; costa with three sections in proportion of 67: 15: 10, r-m before middle level of cell dm (15: 20), M1 ratio about 2.5, ultimate section of CuA1 slightly shorter than 1/2 length of penultimate section (8: 18). Fore femur with several short fb; fore and mid tibiae each with very short dp, mid tibia with one long and one short spur.

Epandrium with surstylus ( Fig. 24 ) inverted-L-shaped, bearing minute apical spinule; cercus small; proctiger Y-shaped. Phallapodeme 400 µm long; pregonite with seven setulae apically, postgonite with six setulae. Basiphallus ( Fig. 23 ) short; mesophallus rather long, curved at distal end, striated on distal part; distiphallus 460 µm long, almost membranous, with microscopic scales on basal part; paraphallus very narrow, with right sclerite longer than left one.

Body length 3.0–3.5 (3.5) mm.

FEMALE. Similar to male, but dark spots on mesoscutum broader than those of male, extending to lateral margins of scutum; anespisternum almost entirely black, with anterodorsal corner yellow; brown area of anatergite and katatergite extending anteriorly to anepimeron and posteriorly to lateral margin of mediotergite; hind tibia pale brown on basal half; T1 and T2 yellowish brown but blackened laterally, T3 and T4 black with posterior margins yellowish, T5 and T6 entirely black, T7 brown at base and yellowish posteriorly; ovipositor brownish yellow, with base brown; wing length 3.4–3.8 mm, second and third costal sections in proportion of 75: 15, M1 ratio 2.4–2.9; body length 3.2–4.3 mm.

Distribution. Laos.

Remarks. The male genitalia of this new species are almost similar in appearance to those of its known congeners. However, this species is clearly distinguished from the Australian Tetrameringia ustulata and the Japanese T. borealis Sueyoshi, 2006 , by the coloration of the mesoscutum and wing, the numbers of or and sc, and the plumosity of the arista. In T. ustulata , the mesoscutum is unmarked and the wing has a blackish mark extending from the costa to CuA1 across the end of cell dm in addition to the anteroapical mark, or are four, lsc are three, and the longest pubescence on the arista is about 1/5 as long as the width of the first flagellomere ( McAlpine 1960: figs 1, 5); in T. borealis , the mesoscutum is brown bivittate along lateral margin of the scutum, with the marking extending onto the scutellum, the anteroapical marking on the wing is smaller (not beyond R4+5; Sueyoshi 2006: fig. 9H), bsc and lsc are absent, and the arista is sparsely and shortly plumose.

Etymology. The specific name refers to the spotted mesoscutum (Latin: maculatus).

Figures

FIGURES 19 – 24. Male genitalia of Sobarocephala megastylis sp. nov. (19 – 22, holotype) and Tetrameringia maculata sp. nov. (23, 24, paratype). See Figs 1 – 3 for explanation of parts. Scale = 0.1 mm.