Silba malaysia, Introduction & Fallén & Morge, 2007

Introduction, Iain, Fallén, Lonchaea & Morge, Setisquamalonchaea, 2007, New pecies of Lonchaeidae (Diptera: Schizophora) from Asia, Zootaxa 1631, pp. 1-32 : 25-26

Silba malaysia sp. nov.

The holotype is slightly damaged with many large setae on the thorax and scutellum broken or missing

Description. Holotype male: Head: Eyes bare. Frons approximately half eye width, parallel sided, subshining and flat, with short frontal and interfrontal setulae which are less than one quarter length of orbital setae, longer setulae on anterior margin above lunule. Orbital plates shining and relatively wide, bare apart from the orbital setae. Lunule, parafacials and face entirely silver dusted apart from face immediately dorsal to the mouth margin which is shining black. Lunule with three to four setulae on each side. Anterior genal setulae forming a single row of four to five along mouth margin, basal of these the strongest setulae on genae but not markedly stronger than any of the others. Antennal flagellomere comparatively small; approximately two and a half times as long as deep, entirely black apart from basally on the inner surface with a small orange brown area, lying immediately apically of this is a small silver dusted area. Arista with plumosity at its greatest extent slightly wider than depth of the antennal flagellomere.

Thorax: disc shining apart from some sparse dusting in pre-scutellar area and on pleurae. Anepisternum with three strong anterior setae and four posteriorly. Katepisternum with two strong setae, a number of finer setulae present on the anterior part of the sclerite. One very long propleural setae, as long and as strong as the anterior setae on the anepisternum, a single stigmatical setae half this length. Scutellum dusted on the disc, on the margin with two setulae between apical setae and two between lateral and apical setae. Squamae pale with dark fringes. Wings lightly tinged with yellow. Wing length 4.0mm. Legs entirelly black, hind tibiae thickening slightly towards apex and covered in longer fine setulae

Male terminalia: Figs. 53–55. In lateral view epandrium almost twice as high as wide, widest part on the lower half, smoothly curved on ventral margin and with a distinct anterior process. Ventral margin with long setulae especially posteriorly where their length is approximately half the height of epandrium. Cerci rather small and rectangular, only about one third height of epandrium, bearing short setulae on dorsal and posterior margins. Surstyli projecting posteriorly as a blunt process only slightly from beyond epandrium shell, anteriorly forming a hook-like projection. In ventral view margin of surstyli with a row of moderately long setulae, inner surface of surstyli with eight small black teeth in a single row, the uppermost of these projecting posteriorly beyond the shell of the epandrium. Aedeagus J-shaped, apical section slightly twisted near base, upper part broadening out slightly towards the apex.

Differential diagnosis: This species belongs to the Silba abstata McAlpine, 1956 group of species all of which are rather small, with a relatively short antennal flagellomere, an elongate epandrium with short cerci and with a row of teeth on the inner surface of the surstyli situated parallel to the ventral margin. The characteristic aedeagus with its slightly twisted and fluted apical section is however distinctive.

TYPE MATERIAL: Holotype male. MALAYSIA: 88 km. from Kuala Tringganu , on road from Kuantan, 16.viii.1986, leg. K. C. Khoo.

Only known from the holotype in the AMS.

Etymology. The specific epithet is derived from the country of capture of the holotype.