Silba mbuti
Description. Male : Head : Eyes bare. Frons 0.5x width of an eye, subshining black, 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. Lunule with dull orange ground colour, covered in silver pollinosity as to a lesser
extent are parafacials and face. Anterior genal setulae in a single row of 6 along mouth margin, these slightly
separated from and slightly stronger than the other setulae. Antennae; 1st flagellomere black apart from an obscure
brownish area at extreme medial base, length to depth ratio 3.2:1. Arista long plumose, ratio of plumosity at
maximum extent to depth of 1st flagellomere 1.4:1.
Thorax: mesonotum subshining blue black. Anepisternum 3 anterodorsal and 3 posterior setae. Katepisternum
with 2 setae near the dorsal margin, the posterior longer and stronger than the anterior. Proepimeron and
proepisternum each with 1 seta. Scutellum with disc almost as subshining blue black as the thoracic disc, on margin
between lateral and apical setae with two setulae on each side, none between apical setae. Calypteres and fringes
slightly yellowish white. Wings clear, wing length 3.7mm. Legs entirely black, basal tarsomeres yellow/brown,
apical segments darkened.
Male terminalia (Figs. 17–18): epandrium and associated structures of the standard S. admirabilis group type.
Phallus: basal plate, in ventral view kite-shaped, widening steadily for basal two thirds, then narrowing to apex,
apical incision a rather deep U-shape. In lateral view basiphallus rather broad, bearing spicules, basal plate as long
as phallus.