1986] Wiggins & Richardson — Onocosmoecus 191 
warts with pale setae, not as dense or long as in Dicosmoecus spp. 
(except D. obscuripennis Banks); mesepisternum lacking second 
setal wart. 
Male genitalia (Figs. 2, 4, 11, 12). Segment IX broader laterally 
than in Dicosmoecus , sternum not extended posteromesally. Seg- 
ment X with external branches broad, flattened, longer than basal 
segment of inferior appendages, fused to segment IX close to mid- 
dorsal line dorsad of internal branches; internal branches variably 
fused together dorsally, inferior branches lacking or occasionally 
represented by small process, or well developed and prominent; 
subanal plate cleft mesally, truncate apically. Phallus bearing pair of 
stout spines ventrally at base of aedeagus; parameres partially and 
variably fused with aedeagus, each expanded into membranous 
apex bearing 1-6 stout spines, the arrangement, number and length 
of these spines extremely variable and in more than 50 per cent of 
specimens examined spines differ on each paramere of a single 
individual. 
Female genitalia { Figs. 3, 5, 6, 7, 13). Highly variable in structural 
detail. Segment VIII variably sclerotized ventromesally. Segment 
IX with massive rounded tergal lobes extending ventrolaterally to 
sternum IX which is here interpreted as reduced to a very small lobe 
or fold on each side of flattened vulval lobe; vulval lobe subdivided 
into three parts apically but continuous basally, median part varia- 
ble in shape, lateral parts concave mesally and variable in shape. 
Segment X elongate, forming anal tube, open ventrally, variably 
cleft dorsomesally; in ventral aspect, basal shoulders of segment X 
highly variable in shape even within single series, frequently 
extended into angulate ledge or tooth at each side. 
Larva. (Fig. 8). Broad, light coloured median band extending 
from coronal suture, over pronotum and mesonotum; sclerites of 
head, pronotum and mesonotum with dense, minute spines. Prono- 
tum lacking stout spines along anterior margin, but with row of 
12-16 long, black setae just behind anterior margin, pair closest to 
mid-dorsal line distinctly shorter, space between these setae and 
next seta on either side narrower than that between remaining setae 
of row (character valid at least to LIII); pronotum and mesonotum 
with sparse, short yellowish and longer dark setae. Metanotal setae 
confined to setal areas, variable: sal 4-15, sa2 3-13, sa3 9-26; metep- 
imera each with approximately 8-15 setae. Setae on or near ventral 
