178 P. E. S. WHALLEY 



Key to the Subspecies of CECIDOTHYRIS PEXA Hampson 



1 Dark brown pattern on median and basal area of fore and hind wings p. guttulata (p. 179) 

 - Pale brown pattern on median and basal areas of fore and hind wings . p. pexa (p. 178) 



Cecidothyris pexa pexa (Hampson) comb. n. 



(PI. 2, N; PI. 23, figs 125, 126; PL 46, fig. 264; PI. 68, figs 438, 439) 



Rhodoneura pexa Hampson, 1906 : 117. 

 Rhodoneura pexa Hampson; Dalle Torre, 1914 : 30. 

 Oxycophina pexa (Hampson) Gaede, 191 7 : 369. 

 Oxycophina pexa (Hampson); Gaede, 1929 : 494. 



o\ Wing, 10-5-18 mm. Vertex brown, irrorate with white, frons rounded, usually narrower 

 than long, occasionally enlarged. Antennae strongly bipectinate. Labial palps with second 

 segment slightly longer than first, short, not reaching vertex. Thorax brown, irrorate with 

 white. Outer spur of hind tibia slightly shorter than inner. First hind tarsal segment more 

 than 2 X length of tibial spur. Fore wing, pattern as in PI. 2, N, pale brown with darker brown 

 markings. Fore wing pattern slightly obscured by a light dusting of scales. Underside, pattern 

 of median and basal areas very dark brown with prominent reticulations. Terminal and 

 subterminal areas as on upperside. Radial veins usually from cell. Veins iA and 2A forming 

 loop at base, joining to form single vein to wing margin. Frenulum with one bristle. Hind 

 wing, median and basal areas darker than terminal with prominent reticulate pattern. Under- 

 side with median fascia darker. Sc+Rt and Rs free. 



Genitalia <J (PI. 46, fig. 264). Uncus simple, gnathus present, valve simple. Juxta with 

 spiny lateral lobes. Aedeagus with vesica covered with minute spines. 



$. Wing, 12-5— 19 mm. Colour and pattern as male, sometimes a darker brown. Frenulum 

 with 3 or 4 bristles. 



Genitalia $ (PI. 68, figs 438, 439). Anal papillae short. First part of duct lightly sclerotized. 

 No signum. 



Discussion. This subspecies is separated from C. pexa guttulata Aurivillius 

 by its paler colour and more obscured pattern on the fore wing. Even a series of 

 very small specimens from Blauwkop (S. Africa), in which the pattern is very faint, 

 is otherwise morphologically similar to the rest of the specimens of pexa pexa. In 

 Rhodesia, where both subspecies occur, there is a tendency for intermediates to 

 occur which are difficult to assign to either subspecies. The shape of the frons 

 varies, in most specimens of p. pexa the frons is fairly narrow and not swollen whereas 

 in p. guttulata the frons is usually swollen and much enlarged. This seems to be 

 fairly constant in p. guttulata although small specimens of this subspecies from Tan- 

 zania have a narrower than average width frons. There seems to be a trend to 

 produce a less bulbous frons in the subspecies p. pexa than in p. guttulata. The 

 enlarged frons is also found in C. tyrannica Whalley but not in C. chrysotherma 

 Hampson. C. p. pexa has been bred from Terminalia sericea, where it forms galls 

 on the twigs (PI. 23, fig. 126), see p. 19. 



Distribution. Map 73. Rhodesia; South West Africa; Botswana; Lesotho; 

 South Africa. 



Material examined. 



Holotype c?, South Africa: C[ape] Colony, 99-336, BM slide no. 9041, in BMNH. 



Rhodesia: i $, Bulawayo, iii.1925 (Higgins), in CMP; 2 $, Khami, nr Bulawayo, 



