Silba bakongo
Description. Male: Head: Eyes bare. Frons 0.6x width of eye, subshining black, dulled by microsculpture, frontal
and interfrontal setulae less than 0.25x length of orbital seta. 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 6–7 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 3.5:1. Arista plumose, ratio
of plumosity at maximum extent to depth of antennal postpedicellus 1.1:1
Thorax: Mesonotum subshining blue black. Anepisternum with all setae either broken or obscured by the
mounting pin and glue. Katepisternum with 2 setae near dorsal margin, the posterior longer and stronger than
anterior. Proepimeron and proepisternum each with 1 seta. Scutellum with disc grey dusted, on margin between
lateral and apical setae with one setula on left side, none between apical setae. Calypteres white with white fringes.
Wings clear, wing length 3.2mm. Legs entirely black, basal tarsomeres slightly darker orange than in other species,
apical segments darkened.
Male terminalia (Figs. 3–4): epandrium and associated structures of the standard S. admirabilis group type.
Phallus: basal plate, in ventral view widening evenly from base to apex, at apex forming two parallel sided
processes separated by a deep, wide U-shaped incision. In lateral view basal plate extending past the apex of the
phallus, apices expanded and laterally flattened, resembling paddles. Basiphallus of normal size, with only a few
small spicules.