Syndyas brevior de Meijere, 1910

Grootaert, Patrick & Yang, Ding, 2009, A New Syndyas Loew, 1857 (Diptera: Hybotidae: Hybotinae) From Mangroves In Singapore, With A Review Of The Oriental And Australasian Species, Raffles Bulletin of Zoology 57 (1), pp. 17-24 : 19-20

Syndyas brevior de Meijere, 1910

( Figs. 2 , 8 , 10 )

Syndyas brevior de Meijere, 1910: 68 , Fig. 5 (wing).

Material examined. – Lectotype female INDONESIA [E. Jacoboson Lang Eiland Krakatau Mei 1908] [ Syndyas brevior det. de Meijere type] red label [ Syndyas brevior de Meijere 1910 ZMAN type DIPT.0476.1]; 1 female [E. Jacobson. Verlaten Eiland Krakatau Mei 1908] red label [ Syndyas brevior de Meijere 1910 ZMAN type DIPT.0476.2]

Diagnosis. – A small species with clear wing membrane, no stigma and discal cell much shorter than basal cells. Hind femur thickened on apical 2/3 with a ventral row of spiny bristles, about half as long as femur is wide. Hind tarsomere slightly thickened and much shorter than following tarsomeres together.

Redescription. – Female: length: 2 mm; wing: 1.75 mm.

Head. Eyes holoptic, frons and face linear. A pair of proclinate ocellars as long as all antennal segments together. Postoculars short, black, with tips proclinate over the eye. Antenna black, third segment elliptical 3 times as long as wide. Arista missing. Palp and proboscis hidden.

Thorax black in ground-colour, with thin pale brownish pubescence. Mesonotum shining black on anterior 2/3, posterior third thinly covered (subshining) with brownish dusting. Pleura grey dusted. Large thoracic bristles brown. Acrostichals long biseriate, the rows widely separated; dorsocentrals uniseriate but with numerous hairs at sides, ending in a long prescutellar. A pair of long brown apical scutellars and some shorter marginal hairs on both sides.

Legs brownish-black. Fore femur without ventral bristles, a few fine black posteroventrals near tip. Fore tibia ( Fig. 8 ) somewhat curved in dorsal view, slightly dilated, especially around the opening of the tibial gland, opening of the tibial gland not distinct; tibia with 2 short dorsal bristles and with a row of long posteroventrals, a little longer than tibia is wide, the row continuing on tarsomere 1. Tarsomere 1 with some long dorsal bristles, especially a basal one and a pair of apicals; following tarsomeres also with distinct dorsal hairs. Mid femur ventrally bare. Mid tibia with 4-5 brown dorsal bristles, twice as long as tibia is wide and a very long ventral preapical; a row of long brown posteroventrals. Mid tarsomere 1 with two long dorsals and a row of long posteroventrals and a long ventral near base. Hind femur club-shaped, slender on basal third, gently widening towards tip, near tip about twice as wide as at base, ventrally with a row of equally long spine-like bristles. Hind tibia clubshaped, narrow at base but quickly widening towards tip, at its widest part, 3 times as wide as at base ( Fig. 10 ) dorsally with 3-4 long black bristles, in addition a pair of preapical dorsal bristles. Hind tarsomere 1 thickened, about half as long as following four tarsomeres together; with a pair of long preapical bristles.

Wing ( Fig. 2 ) clear, without stigma. Discal cell short; basal cells about 1.5 times as long as discal cell. Vein R 4+5 and M slightly converging near wing tip and ending parallel into costa.

Abdomen shining black. Tergites dorsally with short pale brownish bristles; basal tergite with long brown bristles at sides. Apical two segments and cerci brown dusted.

Comments. – Frey (1938) reports a male from the Philippines, unfortunately not giving any details. It is clear that in the future these specimens should be examined in order to try to establish conspecificity with the holotype female of Krakatau .

Figures

Figs. 1–4: Syndyas wings: 1, S. singaporensis, new species; 2, S. brevior de Meijere; 3, S. aterrima de Meijere; 4, S. elongata de Meijere.

Figs. 5–8. Syndyas fore tibia posteriorly: 5, S. singaporensis, new species; 6, S. aterrima de Meijere; 7, S. elongata de Meijere; 8, S. brevior de Meijere.

Figs. 9–12. Syndyas hind leg: 9, S. singaporensis new species; 10, S. brevior de Meijere; 11, S. aterrima de Meijere; 12, S. elongata de Meijere.