Silba upemba
Description. Male: Head : Eyes bare. Frons 0.5x width of an eye, slightly brown with aging, dulled by
microsculpture, frontal and interfrontal setulae less than 0.25x length of orbital seta, longer setulae present
anteriorly above lunule. Orbital plates shining black, bare apart from the orbital seta.. Lunule with black ground
colour, covered in silver pollinosity as to a lesser extent are parafacials. Anterior genal setulae rather short in a
single row of 6 along mouth margin, these slightly separated from the other setulae. Antennae; 1st flagellomere
black apart from an obscure brownish area at extreme medial base, length to depth ratio 3:1. Arista plumose, ratio
of plumosity at maximum extent to depth of 1st flagellomere 1:1.
Thorax: mesonotum subshining blue black. Anepisternum 2 anterodorsal 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 the lateral and apical setae with 4
setulae on each side, none between apical setae. Calypteres and fringes distinctly golden. Wings clear, wing length
3.6mm. Legs entirely black, basal tarsomeres yellow/brown, apical segments darkened.
Male terminalia (Figs. 25–26): epandrium and associated structures of the standard S. admirabilis group type.
Phallus: Basal plate, in ventral view widening only slightly from base, almost parallel sided but with a pair of
lateral serrations at half way point, apically without any obvious incision, lateral margins more produced than the
centre, the entire apical margin being covered in a loose row of spinules