Thinophilus puniamoorthyae, Grootaert, 2018

Grootaert, Patrick, 2018, Revision of the genus Thinophilus Wahlberg (Diptera: Dolichopodidae) from Singapore and adjacent regions: A long term study with a prudent reconciliation of a genetic to a classic morphological approach, Raffles Bulletin of Zoology 66, pp. 413-473 : 453-457

Thinophilus puniamoorthyae sp. nov.

(Figs. 41, 42)

Material examined. Holotype Male. SINGAPORE, Sungei Buloh Wetland reserve (SB1), 18 September 2013, (reg. 30150, Ma5873; ZRC _ BDP00004499 ).

Paratypes: 1 male, Sungei Buloh Wetland reserve (SB1), same provenance as holotype, ( ZRC _ BDP00004539 ) . 1 male, Sungei Buloh Wetland reserve (SB1), 13 August 2013 (reg. 30086; ZRC _ BDP00004500 (specimen lost after sequencing) ; 1 male, Sungei Buloh (SB2), 3 July 2013 ( ZRCBDP0117694 ) ; 1 female, Sungei Buloh (SB1), 23 January 2013 ( ZRCBDP0120000 ) ; 1 male, Sungei Buloh (SB1), 7 July 2013 ( ZRCBDP0095272 ) ; 1 male, Sungei Buloh Fig. 41. Thinophilus puniamoorthyae sp. nov. holotype male. A, Epandrium ventrally; B, Epandrium and cercus laterally; C, Cerci dorsally. Scale = 0.1 mm .

(SB1), 13 August 2013; 1 female, Sungei Buloh (SB1), 30 October 2013 ( ZRCBDP0094304 ); 1 female , Sungei Buloh (SB07), 16 May 2016 ( ZRCBDP0082414 ); 1 male , Sungei Buloh (SB08), 14 March 2016 ( ZRCBDP0082618 ) .

Etymology. This species is dedicated to Jayanthi Puniamoorthy (NUS) who coordinated the 2-year sampling campaign of the Mangrove Insect Project.

Diagnosis. Medium-sized species with yellow palpus; antennae yellow; third antennal segment higher than long, with a small apical tip; arista subapical; fore coxa anteriorly brownish, laterally more yellowish, posterior four coxae black, legs further yellow but apical tarsomere of all legs brown. Mid femur with 2 pairs of ventral bristles at base, most basal one twice as long as femur is wide. Fore tibia with a short anterodorsal only. Five dc (4 almost equally long). Genital capsule brown, cerci whitish.

Male. (Fig. 40) Body length 2.5 mm; wing length 2.5 mm.

Head. Frons and face with dark metallic green ground colour. Face below middle, as wide as depth of third antennal segment. Palpus yellow with black bristly hairs. Rostrum large, dark brown with white hairs. Postcranium shining dark metallic green. 2 long diverging ocellars; 2 shorter converging verticals, pointing forward; 2 distinct postverticals. Postoculars above black and uniseriate, longer below and whitish with a few additional white long hairs behind them.

Antenna yellow, with extreme tip of third segment brown. Lateral margin of second segment black; with long dorsal and ventral bristles. Third segment higher than long, apically blunt with a minute apical tip. Arista subapical, 2.5–3 times as long as antenna, black, shortly pubescent; basal aristal segment short, black.

Thorax and scutellum shining dark metallic green; no dull black spots. No acr; 4 almost equally long dc, preceded by a short bristle. Scutellum with 2 marginals, with a minute lateral hair at outer side. 5 upper and 3 lower white propleural bristles.

Legs yellow with black hairs and bristles, but all coxae black, extreme tips paler brownish. Fore coxa however paler brown at side. Apical tarsomeres of all legs brown.

Fore leg. Coxa anteriorly on basal half with minute black bristles; on apical half some black bristles as wide as coxa; tip of coxa with moderately long bristles. Femur slender, a little thickened in basal third; no ventral bristles, apart from some minute hairs; in basal quarter a row of erect posterior hairs; some short preapical pv; at least 3 long posterior bristles at base and some long posterior preapicals. Tibia with a short bristle on basal third and apical third; ventrally with inconspicuous bristles. Tarsomeres with a pair of weak apical bristles.

Mid leg. Coxa with a long black exterior bristle nearly as long as coxa, and rather short bristles anteriorly. Femur thickened in basal two thirds, nearly as wide as fore femur. Anteriorly with a long preapical and a row of 4 posteroventrals near tip. Ventrally near base 4 bristles with most basal bristle longer than femur is wide, others shorter. Tibia with 1 strong ad, pd near middle and some apicals. Tarsomeres with distinct apical bristles.

Hind leg. Coxa with a long, black exterior bristle (shorter than on mid tibia). Hind femur stouter than mid femur. An anterodorsal bristle on apical quarter and an anterior near middle; preapically a short anteroventral and posteroventral. Ventral hairs minute. Tibia with 2 dorsal (pd) and a longer ad near middle A crown of strong apical bristles.

Wing feebly brownish tinged, without darker shades. Veins brownish, paler near base. Apical part of M 1+2 practically straight; Apical part of M 3+4 1.5 times as long as tp. Anal vein dark brown at its base, indicated for a little more than half its length. Halteres white. Squama white, with pale cilia.

Abdomen with a shining metallic green ground-colour. Tergites covered with short black bristles and somewhat longer marginals. Sternite 1 not sclerotised, lacking bristles. Sternites 2–4 with fine hairs. Male terminalia as in Fig. 41. Cercus whitish, epandrium with base of surstyli brown.

Female. Unknown.

Remarks. Thinophilus puniamoorthyae sp. nov. was originally not recognised among the more than 2,000 specimens of T. simplex sp. nov. that were recorded during the MIP mangrove survey in Singapore. It has the same size and weakly bristled legs. The fore coxae being not entirely black was considered as variability. The four fine, but distinct bristles at the base of the mid femur were overlooked in the new species. The species became apparent only when 3 specimens originally identified as T. simplex appeared in a different NGS barcode cluster which was confirmed morphologically. T. simplex sp. nov. has completely black fore coxae and no bristles at the base of the mid femur. The tip of the postpedicel has a brown rim in lateral view in T. simplex sp. nov., while the postpedicel is completely yellow in T. puniamoorthyae sp. nov. Both species are sympatric.

T. puniamoorthyae sp. nov. is also very similar to T. peninsularis Parent, 1935 . The latter with a body size of only 2 mm is even smaller than T. puniamoorthyae sp. nov. It has also all apical tarsomeres brown, but the tarsomere 1 (protarse of Parent, 1935) of the fore leg is as long as following tarsomeres together and the fore tarsus is longer than the fore tibia. In T. puniamoorthyae sp. nov. tarsomere 1 is shorter than the following tarsomeres together and the fore tarsus is as long as the fore tibia. Mid tarsomere 1 in T. peninsularis is also as long as the following tarsomeres, but shorter in T. puniamoorthyae sp. nov. The most distinctive feature is the presence of a number of long ventral bristles at the base of the mid femur. Although there are a few longer bristles in T. peninsularis , they are not so long as in T. puniamoorthyae sp. nov.

Thinophilus setiventris Grootaert & Meuffels, 2001 (Figs. 42, 43)

Thinophilus setiventris Grootaert & Meuffels, 2001: 344 (Figs. 13–16). Type locality: Thailand, Ranong province, Wat Tapo Taram .

Material examined. SINGAPORE, 1 female, Clementi woods, drains, 6 March 2005, (reg. 25002, Si363, leg. PG) ; 3 males, 4 females, Clementi woods, drains, 23 April 2005, (reg. 25084, Si748, leg. PG) ; 7 males, 12 females, Clementi woods, drains, 25 June 2005, (reg. 25182, Si847, leg. PG) ; 2 males, 1 female, Pulau Ubin, fresh water pools, 12 September 2005, (reg. 25340, Si1033, leg. PG) ; 1 female, Sungei Buloh , mangrove, 25 May 2005, (reg. 25163, Si1210, leg. PG) ; 9 males, 8 females, HortPark , 23 November 2017, lawn in park (Mal.) .

SMIP & MIP material: 1 male, Sarimbun, SR 1, mangrove, 25 June 2014 (reg. 30548, Si 2621, Mal.) ; 1 male, Semakau new, SMN1, mangrove, 10 January 2013 (reg. 29677, Ma 2330, Mal.) ; 2 females, Semakau new, SMN1, mangrove,

Fig. 42. Thinophilus setiventris Grootaert & Meuffels, 2001 , male habitus. 7 February 2013 (reg. 29729, Ma3330, Mal.); 1 female, Semakau new, SMN2, mangrove, 17 January 2013 (reg. 29691, Ma2377, Mal.).

MALAYSIA, 1 male, 1 female, Tanjung Leman, Mersing District , Johor, 23 December 2005 (reg. 25460; Si 1354; leg. P. Grootaert) .

Fig. 43. Thinophilus setiventris Grootaert & Meuffels, 2001 , male terminalia. Epandrium and cercus laterally. Scale = 0.1 mm.

Fig. 44. Thinophilus simplex sp. nov., male habitus. Diagnosis. Medium-sized, green metallic species with dull black spots on mesoscutum. Palpus, antennae and fore coxae yellow. Wing with grey spots on apical third of R 4+5, on wing boss and on Tp. Third sternite in male with a cluster of long, black hairs.

Bionomics. Grootaert & Meuffels, 2001 described this species as being a marine species since it was originally found in a riverbed close to the sea. I have now evidence that it is a fresh water species. In Singapore I never found it in the mangroves, or it was in areas with fresh water. It seems to be an anthropogenic species since it is often observed in man-constructed habitats such as the rain water drains running through parks in Singapore. There it is often observed in the company of Tachytrechus tessellatus . Several times it was found in large numbers after heavy rain fall in a prairie and a lawn in a park where normally no water bodies are present.

Males were often observed with Laboulbeniales on the sternites.

Phenology. Active the whole year round.

Distribution. Thailand (Ranong prov.), Malaysia and Singapore.