Silba virescens 1851
Descrip=tion of S. pectita (junior synonym)
Medium sized; rather dull black species, with whitish calyptrae
and fringes, and black tarsi. Face full and flat. Frons with a transverse depression.
Orbital plate bare above orbital bristleMale.—Size and color as in >8. amitan. sp. Head slightly wider than high (11.3:9.0).
Compound eye bare. Frons slightly longer from anterior ocellus to lunule than wide
at former (6.1:5.75); narrowing slightly to a point below middle, then broadening
to lunule; thinly greyish pollinose, rather sparsely hairy; with a distinct transverse
depression in front of anterior ocellus and orbital bristles, this depression deepest
and broadest in middle. No hairs arising dorsad of orbital bristle. Postocellar bristles
as in amita. Postocular setulae longer than in that species. Lunule orange-brown;
with three or four setulae on each side; whitish pollinose. Face full and flat; with
little or no median carma above and scarcely concave immediately above the oral
margin. Cheek, in lateral view, almost linear; in ventral view, wider than third
antennal segment; with a single row of oral setulae, upper setula distinctly vibrissalike.
First and second antennal segments dark brown. Third antennal segment
,ostly dull brown; orange at inner base; slightly more than three times as long as
wide (7.1 :2.3). Plumosity of arista slightly more than half as wide as third antennal
segment. Palpus approximately as wide as third antennal segment; more than twice
as long as wide.
Thorax, wings, calyptrae, legs and tarsi as described for amita. Apex of scutellum
usually bare, rarely with a pair of weak setulae in female.
Genitalia (Figs. 89, 93). Surstylus deeply incised in middle; posterior lobe raised,
with a comb-like row of teeth arranged in a semicircle, in side view resembling a
cat's paw with claws exposed. Aedeagus unjointed; base bearing scale-like spicu¬
les.
Female.—Similar to male with usual sexual differences. Frons parallel-sided;
wider than long (7.0:6.0).
Ovipositor short and broad as in apodesma n. sp. (Fig. 108). Sides of penultimate
segment almost parallel in dorsal and ventral views. Apical segment similar to that
of fraterna McA. (Figs. 114, 115); bases of proximal dorsal hairs much farther apart
''"an in fraterna; slightly longer and stronger than subapical lateral hairs. Spermao^
ieca somewhat longer and more slender than in fraterna
Egypt - recorded reared from roots of sugar cane
Sudan - "from dura"
Tanzania - bred from Pennisetum purpureum also known as Napier grass, elephant grass or Ugandan grass which is a species of perennial tropical grass native to the African grasslands