Teuchophorus meieri, Grootaert, 2006

Grootaert, Patrick, 2006, The Genus Teuchophorus (Diptera: Dolichopodidae) In Singapore, Raffles Bulletin of Zoology 54 (1), pp. 59-82 : 69-71

Teuchophorus meieri , new species

( Figs. 22-24 )

Material examined. – Holotype male: SINGAPORE: Nee Soon , 5 Apr.2005, Malaise trap in swamp forest (25048, coll. P. Grootaert, Si 665).

Diagnosis. – Medium-sized species with yellowish antennae. No acrostichals. 4 black dc. Bristles on head, thorax and legs black. Legs poorly bristled. Costa not thickened. Hypandrium symmetrical. Prosterna yellow, with a central brown spot. Upper third of mesopleura brown, lower two thirds yellow. Description. – Male. Body length: 1.5 mm, wing length: 1.25 mm.

Head. Frons and face with greenish blue black ground-colour, feebly shining. Frons broad. Face wide, at its narrowest point almost as wide as second antennal segment is wide. Palpi brown, each with a short black apical bristle. Rostrum yellowish brown. Occiput greenish black, feebly shining. Chaetotaxy as usual, all bristles black; 2 very short postocellars. Antenna ( Fig. 22 ) short, yellowish brown; third segment hardly as long as wide, with a short, blunt apex. Arista slightly more than three times as long as antenna; basal aristal segment shorter than third antennal segment.

Thorax. Mesoscutum dark brownish, shining, paler brownish towards sides: humeri, lower part of notopleura, and a narrow stripe from wing root unto scutellum brownish yellow. Scutellum brown. Pleurae yellowish. Upper third of mesopleura brown, lower two thirds yellow, Sternopleura and hypopleura yellow. Bristles on thorax black. No acr; 4 dc. Scutellum with a pair of black marginals. A minute pale propleural bristle.

Legs, including coxae, yellow (including posterior four coxae). Tip of hind femora brown.

Fore leg. Coxa with very short sparse hairs and a row of short brownish bristles at apex. Femur with a very short hair-like preapical pv. Tibia about as long as femur, without bristles or serration. No basal spinule on first tarsomere. Length of femur, tibia and tarsal segments (in mm): 0.36: 0.35: 0.15: 0.08: 0.07: 0.06: 0.07.

Mid leg. Coxa anteriorly and exteriorly with very short hairs, no exterior bristle. Femur with a minute preapical av. Tibia a little longer than femur, with 2 small brown ad (one basal, one median); 1 small pd near base; 2 small bristles in apical crown. Length of femur, tibia and tarsal segments (in mm): 0.49: 0.53: 0.19: 0.11: 0.08: 0.05: 0.05.

Hind leg. Coxa with a very thin and short dark exterior bristle. Femur with 1-2 preapical av and 1 preapical pv, all very short and weak. Tibia hardly longer than femur; 2 (sometimes 3) weak yellowish brown or black dorsal bristles on apical half, and in between them a row of slightly lengthened hairs. First tarsal segment slightly thickened; on its anterior apical rim a fringe of very short brownish hairs. Length of femur, tibia and tarsal segments (in mm): 0.49: 0.49: 0.08: 0.14: 0.08: 0.07: 0.07.

Wing hyaline, slightly brownish tinged, with brownish veins. Costa not thickened, no stigma but the costa between r1 and r2+3 darker brown (not black). r4+5 and m1+2 apically very feebly diverging. Tp short, straight, oblique, much shorter than apical part of m3+4 (about 2: 5). Halter yellow. Squama small, with darkened border, with few short brownish cilia. Abdomen dorsally dark brown or brown, feebly shining,. Venter and sides yellowish. Hairs and hindmarginal bristles on terga extremely short, dark. Hypopygium ( Figs. 23-24 ) moderately large, dark brown, partly blackish, with partly black appendages. Hypandrium with two long arms ( Fig. 23 ). The tip of the arms are enlarged and bifid in lateral view ( Fig. 24 ). In addition, the epandrium bears a pale, lateral lobe on both sides, partly covering the tips of the hypandrium ( Fig. 24 ). (This structure is unique in Teuchophorus and probably not homologous with the epandrial lobe in other groups). Tip of ventral epandrial lobes much enlarged; the lobes are symmetrical in ventral view.

Female unknown.

Etymology. – The new species is dedicated to my host Dr. Rudolf Meier, Associate Professor at NUS and head of the Evolutionary Biology Laboratory.

Discussion. – Teuchophorus meieri , new species, is very similar to T. singaporensis and T. pauper in the absence of acrostichal bristles, the similar size, general colouration, as well as the poorly bristled legs. We refer to the discussion under T. singaporensis to distinguish T. meieri from T. singaporensis and T. pauper .

There are more species without acr especially in the T. gratiosus group. Here in Singapore, there are T. temasek , new species, and T. neesoonensis , new species. The males of both have very long antennae. The females having short antenna, that are however at least as long as wide, are hard to distinguish from T. pauper and T. meieri . T. spinulosus , new species, and T. acuminatus , new species, also lack acrostichals, but have the third antennal segment about 1.5 times as long as wide.

Distribution and habitat. – Singapore. River banks in rain forest.

Figures

Figs.22-24. Teuchophorus meieri, new species, male:22, antenna; 23, hypopygium ventral view; 24, hypopygium lateral view.hy: hypandrium; del: dorsal epandrial lobe; el: epandrial lobe.