Thinophilus spinatoides, Samoh & Satasook & Grootaert, 2017

Samoh, Abdulloh, Satasook, Chutamas & Grootaert, Patrick, 2017, Eight new species of marine dolichopodid flies of Thinophilus Wahlberg, 1844 (Diptera: Dolichopodidae) from peninsular Thailand, European Journal of Taxonomy 329, pp. 1-40 : 23-27

Thinophilus spinatoides sp. nov.

urn:lsid:zoobank.org:act:6B1C7B5E-A676-4A5D-A67A-07CF3E6356D1

Figs 25–29

Diagnosis

A medium-sized species with very long yellow legs. Both male and female with a set of 4–5 long, stiff brown ventral bristles on fore femur. Fore femur spindle-shaped, basal quarter much dilated. Fore tarsomere 1 very long and slender, twice as long as fore tibia. Tarsomere 3 contrastingly yellowish white, tarsomeres 4 and 5 widened, black.

Etymology

The specific epithet refers to the resemblance with T. spinatus sp. nov., also described from southern Thailand.

Type material

Holotype

THAILAND: ♂, Bakan Tohtid, Langu , Satun Province, 6°47′29.8 ″ N, 99°48 ′ 53.5 ″ E, sweep netting, 3 Jun. 2015, A. Samoh leg. ( NHM-PSU ).

Paratypes

THAILAND: 2 ♂♂, 1 ♀, same collection data as for holotype.

Description

Male ( Fig. 25 )

LENGTH. Body 4.5 mm; wing 3.8 mm.

HEAD. Frons and face with shiny dark metallic green ground colour. A pair of long divergent black ocellars. No postocellars. A pair of tiny proclinate verticals at level of front ocellars. Postcranium dark metallic green. Postverticals not differentiated from upper postoculars. Upper postoculars uniseriate, short, black; with a few yellow lower postoculars. Antenna yellowish. Arista dorsal, 2.5–3 times as long as antenna, brown, not pubescent. Basal article short, brown; rest of arista paler. Palpus yellow, with few black bristly hairs. Proboscis dark brown.

THORAX. Thorax and scutellum shiny dark metallic green, with coppery and purple reflections. No dull black spots. Bristles on thorax black. Acr lacking; 7 rather short dc, gradually growing longer toward scutellum, ending in a very long prescutellar. Scutellum with 2 long marginals with a tiny hair at outside. 2 short black propleural bristles.

LEGS. Yellow, with apical 2 tarsomeres of all legs black. Fore coxa with basal quarter darkened; mid and hind coxae black, tip yellow. Coxa anteriorly with a short bristle near base and a long bristle at basal third. Trochanter with short white bristles. Fore femur club-shaped, very thickened in basal quarter; apical ¾ very thin. Ventrally with 4 long black bristles; longest bristle nearly twice as long as femur is wide; others shorter. Fore tibia much longer than femur, without ventral bristling. Fore tarsomere 1 very long and slender, twice as long as fore tibia. Tarsomere 3 contrastingly yellowish white, tarsomeres 4 and 5 widened, black. Mid coxa with a short black exterior bristle above middle; anterior bristles short, black. Mid femur ventrally without bristles; no preapical av. Mid tibia longer than mid femur, with a crown of short apical bristles and 2 minute ad. Mid tarsomere 1 almost twice as long as following tarsomeres. Hind coxa without exterior bristle. Hind femur without ventral bristles; no preapical anterodorsal bristles. Hind tibia with 2 short ad and crown of apical bristles. Hind tarsomere 1 a little longer than tarsomere 2.

WINGS. Uniformly yellowish tinged, without spots. Tp straight, apical part of M 3+4 1.5 times as long as Tp. Anal vein not reaching wing margin.

ABDOMEN. Shining dark metallic green. Hairs and hind-marginal bristles on tergites short, black. Sternites without bristles, except sternite 4 with tuft of short black bristles.

TERMINALIA ( Figs 27–29 ). Phallus long, strap-shaped. Cerci pale brownish, with pale hairs, dorsally fused ( Fig. 29 ).

Female ( Fig. 26 )

LENGTH. Body 4.5 mm long, wing 4.2 mm long.

BODY. Similar to male except for following characters: fore femur basally not so strongly swollen as in male and with 5 strong black ventral bristles up to 3 times as long as femur is wide; tarsomere 1 of fore and mid legs more than twice as long as following tarsomeres together; sternites 3, 4, and 5 with pale bristles.

Distribution

Southern Thailand (Andaman Sea coast).

Remarks

Thinophilus spinatoides sp. nov. is particular in that it has the fore femur with the basal quarter very spindle-shaped and dilated. It is less dilated in T. spinatus sp. nov. Fore tibia much longer than fore femur; shorter in T. spinatus sp. nov. Fore tibia slender and without ad in male, present in female; fore tibia stouter and with 2 long ad in T. spinatus sp. nov. Fore tarsomere 3 contrastingly yellowish white, tarsomeres 4 and 5 much widened, black. Fore tarsomere 3 has the same pale yellowish colour as tarsomeres 1 and 2. Tarsomeres 4 and 5 black, not widened in T. spinatus sp. nov. Only base of fore coxa brown; basal ⅔ of fore coxa brown in T. spinatus sp. nov. Lower postocular bristles yellow; black in T. spinatus sp. nov. Anal vein distinct in basal ⅔; anal vein not distinct at all in T. spinatus sp. nov.

Figures

Fig. 25. Thinophilus spinatoides sp. nov., ♂, habitus.

Fig. 26. Thinophilus spinatoides sp. nov., ♀, habitus.

Figs 27–29. Thinophilus spinatoides sp. nov., ♂, terminalia. 27. Genital capsule, ventral view. 28. Genital capsule, lateral view. 29. Genital capsule, dorsal view.