Ngirhaphium caeruleum, Grootaert & Puniamoorthy, 2014

Grootaert, Patrick & Puniamoorthy, Jayanthi, 2014, Revision of Ngirhaphium (Insecta: Diptera: Dolichopodidae), with the description of two new species from Singapore’s mangroves, Raffles Bulletin of Zoology 62, pp. 146-160 : 154-160

Ngirhaphium caeruleum , new species

( Figs. 11, 12 , 13–16 , 19 )

Material examined. Holotype male, Singapore: Semakau , SMN2, 27 September 2012 (reg. 29483, Ma1307).

Paratypes: Singapore: Semakau : 3 males, SMN1, 3 April 2012, (reg. 29159, Ma0089); 2 males, 1 female, SMN1, 12 April 2012, (reg. 29166, Ma0263); 2 males, 1 female, SMN1, 19 April 2012, (reg. 29183, Ma0317); 1 female, SMN1, 3 May 2012, (reg. 29222, Ma0287); 1 male, SMN1, 17 May 2012, (reg. 29235, Ma0298); 1 male, SMN1, 28 June 2012, (reg. 29313, Ma1016); 1 male, SMN1, 12 July 2012, (reg. 29339, Ma1087); 2 females, SMN1, 26 July 2012, (reg. 29365, Ma1096); 1males, 1 female, SMN1, 6 September 2012, (reg. 29443, Ma1402); 1 male, SMN1, 13 September 2012, (reg. 29456, Ma1411); 1 female, SMN1, 27 September 2012, (reg. 29482, Ma1416); 1 female, SMN1, 4 October 2012, (reg. 29495, Ma2097); 1 male, SMN1, 18 October 2012, (reg. 29521, Ma2100); 5 males, 1 female, SMN1, 25 October 2012, (reg. 29534, Ma2122); 1 male, 1 female, SMN1, 1 November 2012, (reg. 29547, Ma2272); 3 males, SMN1, 8 November 2012, (reg. 29560, Ma2265); 2 males, 1 female, SMN1, 29 November 2012, (reg. 29599, Ma2258); 1 female, SMN1, 6 December 2012, (reg. 29612, Ma2291); 1 male, 1 female, SMN1, 13 December 2012, (reg. 29625, Ma2287); 1 male, 1 female, SMN1, 27 December 2012, (reg. 29651, Ma2288); 4 males, 3 females, SMN1, 10 January 2013, (reg. 29677, Ma2304); 2 females, SMN1, 17 January 2013, (reg. 29690, Ma2302); 1 female, SMN1, 24 January 2013, (reg. 29703, Ma3274); 1 male, 6 females, SMN1, 7 February 2013, (reg. 29729, Ma3278); 1 male, 2 females, SMN1, 14 February 2013, (reg. 29742, Ma3287); 2 males, 2 females, SMN1, 21 February 2013, (reg. 29755, Ma3246); 1 female, SMN1, 28 February 2013, (reg. 29768, Ma3393); 2 males, SMN1, 7 March 2013, (reg. 29782, Ma3413); 2 males, SMN1, 14 March 2013, (reg. 29796, Ma3290); 1 male, SMN1, 21 March 2013, (reg. 29810, Ma3879); 1 male, SMN2, 12 April 2012, (reg. 29167, Ma0324); 1 female, SMN2, 30 May 2012, (reg. 29262, Ma0393); 1 male, SMN2, 23 August 2012, (reg. 29418, Ma1267); 1 male, 3 females, SMN2, 30 August 2012, (reg. 29431, Ma1280); 2 males, 2 females, SMN2, 6 September 2012, (reg. 29444, Ma1421); 2 males, SMN2, 27 September 2012, (reg. 29489, Ma1307); 2 males, SMN2, 25 October 2012, (reg. 29535, Ma2650); 1 female, SMN2, 3 January 2013, (reg. 29665, Ma2300); 1 male, SMN2, 14 February 2013, (reg. 29743, Ma3481); 1 female, SMN2, 28 February 2013, (reg. 29769, Ma3216); 1 male, SMN3, 12 April 2012, (reg. 29168, Ma0179); 2 males, SMN3, 26 April 2012, (reg. 29198, Ma0158); 2 males, SMN3, 3 May 2012, (reg. 29211, Ma0104); 1 male, SMN3, 10 May 2012, (reg. 29224, Ma0142); 1 female, SMN3, 24 May 2012, (reg. 29250, Ma0219); 2 males, 1 female, SMN3, 13 September 2012, (reg. 29458, Ma1360); 1 male, SMN3, 4 October 2012, (reg. 29497, Ma2694); 1 female, SMN3, 18 October 2012, (reg. 29523, Ma2708); 1 female, SMN3, 8 November 2012, (reg. 29562, Ma2269); 1 male, SMN3, 22 November 2012, (reg. 29588, Ma2273); 1 female, SMN3, 10 January 2013, (reg. 29679, Ma2311); 1 female, SMN3, 17 January 2013, (reg. 29692, Ma2313); 1 male, SMN3, 14 February 2013, (reg. 29744, Ma3545); 1 male, SMN3, 21 March 2013, (reg. 29812, Ma3587); 1 female, SMO1, 12 July 2012, (reg. 29342, Ma1140); 1 male, 1 female, SMO1, 10 August 2012, (reg. 29394, Ma1216); 1 male, SMO1, 11 October 2012, (reg. 29511, Ma2793); 1 female, SMO3, 27 September 2012, (reg. 29487, Ma1460); 1 male, SMO3, 18 October 2012, (reg. 29526, Ma2854); 1 female, SMO3, 22 November 2012, (reg. 29591, Ma2256); 1 female, SMO3, 29 November 2012, (reg. 29604, Ma2275); 1 female, SMO3, 14 March 2013, (reg. 29801, Ma3679); 1 male, 1 female, SMO3, 21 March 2013, (reg. 29815, Ma3695).

Diagnosis. A larger species with mesonotum and tergites shining metallic blue. Apical aristal segment thin (filiform) and longer than basal aristal segment. Male with dorsal and ventral surstylus at right side fused; separated at left side. Cerci long, but shorter than surstyli so that they are concealed between the surstyli.

Etymology. The name caeruleum (adjective) means blue in Latin and it refers to the dark blue metallic ground-colour of thorax and abdomen.

Description. Male: Body length: 7 mm; wing length: 5.6 mm (holotype).

Head: Frons shining dark metallic blue (not dusted), sunken between the eyes, wide in front becoming wider behind; ocellar callus small, raised above frons. Face wide, as wide as front of frons, parallel-sided, silvery dusted with a very narrow clypeus (hardly a tenth of length of face). Eyes pass beyond the border of the face; eyes densely set with silvery hairs. Two very long ocellars, directed backward and diverging. Vertical bristles long, half as long as ocellars, rather anteriad on frons at level of ocellar callus, but close to eye border, long, black, directed forward and tips crossing. A pair of long black postverticals directed backward and crossing. Postoculars in upper half strong black in a single row; in lower half white longer and fine; postcranium greenish in ground-colour but grey dusted, below with long fine yellowish white hairs. Palpus long strap-shaped, yellowish with few short black hairs, no bristles. Rostrum in male very small in comparison to the huge rostrum in female; labella brown with long black hairs. Antenna very long, completely black. First segment long, 2.5 times as long as second segment; second segment short, apically with a crown of short black bristles. Third segment very long strap-shaped, laterally flattened, about 6 times as long as wide at base. Arista apical, apical segment much longer than basal segment, almost filiform towards tip. Ratio scape, pedicel, postpedicel, basal aristal segment, apical aristal segment (mm): 0.35: 0.14: 0.98: 0.28: 0.38.

Thorax: Thorax and scutellum with a shining dark metallic bluish ground-colour, covered with a fine grey dusting. A black stripe outside each acr-row. All hairs and bristles black. Pleura more densely grey dusted than mesonotum. Acr biseriate, about 7 pairs, the rows widening a little behind. Presutural dc multiseriate; 6 post-sutural dc: 4 short and 2 long prescutellars. A pair of strong scutellars. A long humeral with a shorter bristle in front; a very strong posthumeral, 2 strong notopleurals, 1 postsutural, 1 supraalar, 1 very strong postalar. All propleural bristles black, 4 short upper and 2 longer black lower propleural bristles (lower one twice as long as upper).

Legs ( Fig. 11 ): Yellow, all bristles black. All coxae greenish black in ground-colour, covered with a fine greyish dusting. All trochanters pale brown. Tip of mid and hind tibiae darkened at tip. All tarsi brownish yellow, becoming darker towards tip. Terminal segments completely black.

Fore leg: Shorter than mid and hind leg. Coxa with short black bristles. Fore femur a little swollen in basal half; ventrally flat, with a row of fine pv in apical half; and av in apical half (could be considered as ventrals). A row of 3 short posterior preapicals and a stronger anterior preapical pointing forward. Fore tibia with 5 strong ad, 4 strong pd and a crown of 4 apicals. All tarsal segments densely set with black hairs and short black bristles. Fourth tarsal segment with a dorsal, asymmetrical forked protrusion, extending over the terminal tarsomere; outer branch of fork half as long as inner branch, tips pointed. Terminal segment with a pair of long normal claws and a thicker claw-like structure beneath the posterior claw. 2 well developed pulvilli and an empodium. Length of tibia and tarsal segments (mm): 1.82: 1.17: 0.42: 0.31: 0.21: 0.23.

Mid leg: Coxa with short bristles anteriorly; no exterior bristle. Mid femur a little wider as fore femur; ventrally with inconspicuous bristles; a strong anterior preapical and 2 tiny posterior preapicals. Tibia with a 5 ad, 5 pd (might be considered as dorsal) and 5 longer av and a crown of long apicals. Tarsal segments 1–4 ventrally at tip with a pair short spinules as well as an apical comb of shorter black bristles. Length of tibia and tarsal segments (mm): 2.86: 1.82: 0.78: 0.65: 0.4: 0.4.

Hind leg: Coxa bare. Hind femur stronger than mid femur, as wide as fore femur; ventrally almost bare; a strong anterior preapical, no posterior preapical. Tibia stronger bristled than mid tibia with 6 long av, 7 ad, 7 pd and crown of long apicals. Segments 1–4 ventrally at tip with a pair short spinules as well as a comb of black bristles. Length of tibia and tarsal segments (mm): 3.9: 1.69: 0.9: 0.52: 0.26: 0.26.

Wing: hyaline, faintly tinged brownish, but anteriorly between costa and R 4+5 with a yellowish tinge. Membrane along veins R 4+5, M 1+2, M 3+4 and Tp sometimes brown to black seamed. Veins dark brown. M 1+2 sharply bent upwards and ending in costa closely near tip of R 4+5. Tp straight, a little longer than apical part of M 3+4. Anal vein well developed. Halter with white knob. Squama white with long white cilia.

Abdomen: Shining dark metallic bluish; tips and sides of tergites with a greyish dusting. Sternites greyish dusted. Tergites densely set with quite long, black bristles; hindmarginal bristles a little longer than the other bristles. Only tergite 5 with very long marginal bristles. Sternites with very short hairs except for the longer marginals on sternite 4. Hypopygium yellowish brown ( Fig. 11 ) sessile with tip of cerci hidden in sternite 4. Cercus shorter than dorsal surstylus (i.e., not surpassing the tips of the surstyli). Apex of cercus slender with a long bristle. Tip of dorsal surstylus set ( Fig. 13 ) with a bundle of yellow bristles. Ventral surstylus at right side fused with dorsal surstylus ( Fig. 16 ); ventral and dorsal surstylus separated at left side. Hypandrium with a large black dorsal protuberance ( Fig. 13 ).

Female: Body length: 8.4 mm; wing length: 6.3 mm.

Body: Body more robust than in male.

Antennae: Antennae about as long as in male, but third antennal segment not as wide. Second aristal segment filiform: length variable from a little longer than basal aristal segment to 1.5 times as long. Ratio of first, second, third segment and basal and apical aristal segments (mm): 0.42: 0.14: 0.84: 0.32: 0.38. Clypeus very large, as long as upper part of face, protruding over rostrum; tip pointed. Rostrum large: in lateral view nearly as long as height of eye. Palpus long, strap-shaped, brownish at base, paler at tip.

Legs: Shape and bristling of legs similar to that of male.

Fore leg: Fourth tarsomere as usual, without protuberance like in male. Terminal tarsal segment with a dorsal apical protuberance and with the usual claws and pulvilli. Ratio of tibia and tarsal segments (mm): 1.82: 1.3: 0.52: 0.52: 0.42: 0.26.

Mid leg: Ratio of tibia and tarsal segments (mm): 3.12: 1.56: 0.65: 0.52: 0.39: 0.36.

Hind leg: Ratio of tibia and tarsal segments (mm): 3.64: 1.56: 0.9: 0.78: 0.42: 0.36.

Figures

Figs. 11–12. Male Ngirhaphium caeruleum, new species (Semakau, Singapore): 11, Habitus with genital capsule removed. 12, Dorsal view of genital capsule.

Figs. 13–16. Ngirhaphium caeruleum, new species (Semakau, Singapore): 13, Lateral view of genital capsule with left ventral surstylus removed; 14, Dorsal view of genital capsule; 15, Lateral, inner view of left ventral surstylus; 16, Fused right dorsal and ventral surstylus.

Figs. 17–19. Ventral view of male genital capsule: 17, Ngirhaphium sivasothii, new species; 18, N. murphyi; 19, N. caeruleum, new species.