Poecilosomella spinipes, Papp, 2002

Papp, L., 2002, Eighteen New Oriental Species Of Poecilosomella Duda (Diptera: Sphaeroceridae), Acta Zoologica Academiae Scientiarum Hungaricae 48 (2), pp. 107-156 : 143-145

Poecilosomella spinipes sp. n.

( Figs 58–64 )

Holotype male ( ROM): INDONESIA: Sumatra, Aceh, Gunung Leuser Nat. Pk., Ketambe Res. Sta., 9–21 SEP 1989, DC Darling, ROM 893087 – 1 ° rainforest. Young forest , Terrace 3, closed canopy, 350 m, 3° 41’N, 97° 39’E, Malaise trap head.

Paratypes: 4 males, 3 females ( ROM, 2 males, 1 female in HNHM): same data as for the holotype .

Measurements in mm: body length 1.95 (holotype), 1.65–1.90 (paratype males), 1.85–2.24 (paratype females), wing length 1.55 (holotype), 1.25–1.95 (paratypes), wing width 0.76 (holotype), 0.66–1.00 (paratypes).

Frons dull red (except for orbitalia), facial plate shiny yellow, cheeks and genae greyish red, genal seta only 0.08 mm long. Antennae reddish yellow, first flagellomere slightly conical towards upper apex, 0.10 mm, scape and pedicel (combined) 0.112 mm. Arista with short cilia only, cilia on flagellomere about as long. Two pairs of medium long but thin ifr.

Mesonotum blackish brown, subshiny, with 4 sagittal, 5 pairs of dorsocentral and 5 pairs of lateral silvery spots (incl. postpronotal stripes). Scutellum slightly shorter than basal width, with 5 silvery spots, lateral basal ones rather large.

Wing rather short, light brown, veins yellow but brown on the area of spots on wing. A brown diffuse spot around humeral vein, between R 1 and Rs fork, around upcurving section of R 2 +3, and a lighter brown patch from R-M cross-vein down to Cu. Costal hairs short and less dense. Second costal section shorter than third section (0.275 vs. 0.375 mm on one male paratype). Vein R 2 +3 without a vein appendage subapically. Vein R 4 +5 more strongly bent towards the costa, i.e. apical part not straight, consequently medial part less curved (basal half slightly S-shaped) .

Legs lighter brown. No parts of fore tarsomeres white, basal half of basitarsi and 2nd tarsomeres and all 4th tarsomeres dark, apical halves and whole 3rd tarsomere light yellow (on all the three legs). Apical part of femora lighter, tibiae with medial and apical broad light rings. Male mid tibia apically not curved inwards and not flattened dorso-ventrally, ventrally without long hairs, ventroapical seta rather short, shorter than basitarsal diameter. Male fore tibia and basitarsus without long hairs, but fore tibia with a row of thick medium-long black spines ventrally ( Fig. 58 ). Female mid tibia with two short ventroapicals, which are much shorter than tibial diameter subapically. Mid tibial armature: anterodorsals at 3/10, 7/15, 7/10, and 9/10 (all medium long), posterodorsals at 2/15 (short), 8/15, 5/6 (very strong).

Abdominal tergite 2 ( Fig. 59 ) desclerotized medially but a small sclerotized plate present in the sagittal line. Male tergite 5 ( Fig. 60 ) membraneous medially, with finely sclerotized hairy lobe laterally. Sternite 6 with a fine lath medially (black on Fig. 60 ); in all, medial complex of sternite 5 & 6 rather simple. Epandrium short, rather small, with medium long setae. Subepandrial sclerite sagittally longer than submedially (i.e. with a small sagittal process), laterally with a hairy spot each. Male surstylus ( Fig. 61 ) blunt, not separated into lobes, basally with a number of caudal setae, posteromedially with the usual blunt tooth, but posteral apical part with a pecten of 11 prensisetae ( Figs 62, 64 ). Postgonite ( Fig. 63 ) of medium width, with a couple of fine hairs only (those mainly on medial surface), its apical 1/5 curved, apex blunt.

Female terminalia characteristic with shiny epiproct, and with 2 pairs of 0.20 mm long downcurved hairs on cerci.

Etymology: It is named on the ventral row of black spines on male fore tibia. Distribution: Indonesia (Sumatra).

P. spinipes sp. n. is an easily recognisable species. The ventral row of thick, medium long black spines on male fore tibia seems unique among the species of the genus. Also the male genitalia show characteristic features in separating it from the other species of the P. varians-nigra species group. The two pairs of very long female cercal hairs are also very characteristic.

Figures

Figs 58–64. Poecilosomella spinipes sp. n., paratype male. 58 = fore tibia with basitarsus, lateral view, 59 = basal abdominal tergites, dorsal view, 60 = sternite 5 (medially torn asunder) with pregenital sternites (moved with the right half of S5), ventral view, 61 = surstylus, lateral (outer) view, 62 = same, inner view, 63 = postgonite, lateral view, 64 = apex of surstylus in dorsal view of pecten. Scales:0.4mm for Fig.59,0.2 mm forFig.60, 0.1 mm forFigs 61–64 (for Fig.58 same asfor Fig.48)