Silba inimvua
Description. Male: Head: Eyes bare. Frons 0.6x the width of an eye, subshining black, dulled by microsculpture,
frontal and interfrontal setulae less than 0.25x length of orbital seta. Orbital plates shining black. Lunule with
brownish ground colour, covered in silver pollinosity as to a lesser extent are the parafacials and face. Anterior
genal setulae in a single row of 6 along mouth margin, these slightly separated from the other setulae. Antennae;
1st flagellomere black, brownish orange colouration at the base of the medial surface more extensive than in the
other species described here, length to depth ratio 2.8:1. Arista plumose, ratio of plumosity at maximum extent to
depth of 1st flagellomere 1.1:1.
Thorax; mesonotum subshining blue black. Anepisternum with 2 anterior and 2 posterior setae. Katepisternum
with 2 setae near the dorsal margin, posterior longer and stronger than anterior. Proepimeron and proepisternum
each with 1 seta. Scutellum with disc heavily grey dusted, on margin between lateral and apical setae with two
setulae on each side, none between apical setae. Calypteres and fringes pale golden. Wings clear, wing length
3.5mm. Legs entirely black, basal tarsomeres yellow/brown, apical segments darkened.
Male terminalia (Figs. 13–14): epandrium and associated structures of the standard S. admirabilis group type.
Phallus: Basal plate a thin transparent structure, in ventral view only slightly widening towards apex where there is
a v-shaped excavation. In lateral view basal plate, shorter than phallus, apex blade-like. Basiphallus swollen
laterally, bearing a few spicules ventrally.