THYRIDIDAE OF AFRICA AND ITS ISLANDS 73 



species differs from the others in the strigifera-group only by the lack of fusion of some 

 of the radial veins in the fore wing. 



This species-group is characterized by the fusion of Sc + R 1 and Rs in the hind 

 wing for part of their lengths, the eyes are without interfacetal hairs and the tarsi 

 have rows of spines on each segment. The African species of this group are very 

 similar externally and can be separated only by differences in the genitalia. 



Striglina strigifera (Strand) comb. n. 



(PI. 8, fig. 31; PI. 31, fig. 166; PI. 53, figs 310-312; Text-fig. 10) 



Plagiosellula strigifera Strand, 1913 : 62. 

 Plagiosella strigifera (Strand) Gaede, 1917 : 372. 

 Plagiosella strigifera (Strand) ; Gaede, 1929 : 496. 

 Plagiosellula strigifera Strand; Whalley, 1964a : 124. 



<J. Wing, 12-14 rnm. Vertex light brown, frons flattened between eyes. Antennae 

 minutely ciliate. Labial palps projecting just beyond frons, slightly longer than diameter of 

 eye, third segment 1/3 length of second. Eyes without interfacetal hairs. Thorax light sandy 

 brown. Hind tibia with proximal pair of spurs shorter and more slender than distal pair. 

 Outer spur of distal pair more than half length of inner spur. Tarsi with spines along length 

 of 1st tarsal segment and 4-6 apical spines on remaining tarsi of hind leg. Fore wing, pattern 

 as in PI. 8, fig. 31, yellowish brown, prominent median brown line and subterminal line which 

 joins or approaches median fascia near costa, pattern strongly reticulate. Indistinct discal 

 spot. Vein R 4 and i? 5 anastomose for a short distance near base. R 3 and i? 4 widely separated. 

 7.A absent. Underside, pattern as upperside but discal spot prominent. Hind wing, pattern 

 as fore wing. Sc+R 1 and Rs join near base for a short distance. 



Genitalia <$ (PI. 31, fig. 166). Uncus with two lateral spines, with small tuft of hairs at base, 

 lateral finger-like process (socii ?) with hairs. Gnathus with slender arms and central process 

 with peg-like teeth. Valves with numerous long hairs, particularly along posterior margin. 

 Valves produced to strong process at apex, variably spined costa of valve at base produced into 

 rounded papilla with long hairs. Juxta with two prominent lateral arms, saccus reduced, 

 aedeagus with two groups of cornuti. VHIth sternite of abdomen with sclerotized plate, 

 posterior margin of characteristic shape (Text-fig. 10). Prominent coremata. 



$. Wing, 15-18 mm. Labial palps 2 X diameter of eye, projecting beyond frons. Patterns 

 as in male, generally darker brown colour. Veins R 3 and i? 4 free, i? 4 and R s widely separated. 



Genitalia $ (PL 53, figs 310-312). Prominent toothed signum in bursa. Anal papillae 

 short, Vlllth sternite and tergite modified. 



Discussion. Some variation was found in the number of spines on the terminal 

 valve process and in the number of cornuti. It is possible that the cornuti are, in 

 part, deciduous, but there is no direct evidence of this. Some of the specimens 

 from Efulen (Cameroon) are a paler brown than the others, but generally there is little 

 variation in colour. This species is one of a group of closely allied species, all of 

 which are similar externally (although with some variation) but which have differences 

 in the male genitalia. Intraspecifically there is little variation in the male genitalia. 

 It would be possible to regard strigifera as a single species with "s. strigifera" as the 

 nominate subspecies with the others as subspecies on the edge of its range. How- 

 ever, in Kivu (Democratic Republic of the Congo) specimens of several of the species 

 have been collected near one another. It is not possible to say, on existing data, 

 that they actually fly together although the data on the few specimens available 



