Silba botanica
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. McAlpine
(1975) provided a key to the known species. With a pale squamal fringe and a simple aedeagus this species is
most closely similar to S. lucens (de Meijere, 1910) from Java and S. imitata McAlpine, 1964 from Australia.
It is distinguished from both these species by having more teeth on the surstylus including one projecting posteriorly
and by the more slender, angled aedeagus.
Description : Holotype male: Head : Eyes bare. Frons narrow, narrowing from level of anterior ocellus to
its anterior margin, at narrowest point approximately one quarter eye width, matt black, dulled with microsculpture,
frontal and interfrontal setulae very short, a few longer ones present along the anterior margin. Orbital
plates without setulae, brightly shining black. Lunule bearing two setulae, orange-brown in ground colour,
covered with silver dusting. Parafacials and upper face also silvered. Anterior genal setulae in a single row offour or five along mouth margin, none of these especially strong. Antennal flagellomere just over twice as
long as deep, entirely black apart from being obscurely brown ventrally basally on inner surface. Arista yellow
basally, long plumose, plumosity at its greatest extent almost twice depth of antennal flagellomere.
Thorax : Disc shining, bearing short setulae at most one quarter length of orbital setae. Anepisternum with
three strong setae anteriorly and three posteriorly. Katepisternum with two setulae, anterior one significantly
weaker and shorter than posterior. One propleural and one finer stigmatical setae. Scutellum slightly damaged,
brightly shining on the disc, apparently with no setulae between the strong setae. Squamae whitish with a
white fringe. Wings clear with light brown veins. Wing length 3.0mm. Legs entirely black. Male terminalia ; Figs. 29 & 30. In lateral view epandrium almost twice as high as s wide, posteriorly
rather pointed and culminating in a short process, anteriorly relatively broad and square ended, semi-circular
excavation on dorsal margin, ventral margin with a row of short setulae along most of its length, a few setulae
dorsally near the posterior apex. Cerci very small, not sclerotised, bearing a row of short setulae along dorsal
margin. Surstyli almost completely enclosed within epandrium apart from a small, rounded anterior projection
on the inner surface, with a continuous row of fourteen small teeth lying parallel to the ventral margin, the
most posterior of these projecting posteriorly beyond shell of epandrium. Aedeagus with basal part relatively
broad with a semi-circular excavation dorsally, outer portion long and narrow, half way along with a 45° bend,
apex slightly flared.