THYRIDIDAE OF AFRICA AND ITS ISLANDS 47 



be separated from this by the prominent brown spot at the apex of the cell in the 

 hind wing of cerussus, and the genitalia are quite distinct. From N. mysticus, to 

 which it is most closely related, it can be separated by the structure of the male 

 genitalia. 



Distribution. Map 4. Democratic Republic of the Congo. 



Material examined. 



Holotype <$, Democratic Republic of the Congo: Prov. Orientale, Opala, 

 Lomami R., iii.1959 (Carcasson), BM slide no. 10481, in BMNH. 



Paratype. Democratic Republic of the Congo : 1 <J, data as holotype. 



Neochrysotypus mysticus sp. n. 

 (PL 23, fig. I2i, PL 27, fig. 145) 



cf. Wing, 15 mm. Vertex white. Antennae minutely ciliate. Proboscis very small. 

 Labial palps upturned, not reaching vertex, third segment 1/3 length of second. Thorax brown. 

 Hind tibia with two pairs of spurs, outer spur of distal pair half length of inner. Fore wing, 

 pattern as in PI. 23, fig. 121, translucent white with black and yellowish brown transverse 

 reticulations. Underside similar. Vein i? 4 and i? 6 joined, coming out of common stem of 

 R 3 +R l +R b . Hind wing, as fore wing. Sc+R t and Rs free. 



Genitalia <J (PI. 27, fig. 145). Uncus short, pointed. Gnathus lightly sclerotized. Basal 

 part of costal margin of valve and transtilla sclerotized and modified, extending posteriorly 

 as two sclerotized arms. Valve broad, with prominent median process, slightly subterminal 

 in position. Process sclerotized and slightly bifurcate. Juxta arms lightly sclerotized with 

 two small basal lobes. Aedeagus with small lateral projection. 



$. Unknown. 



Discussion. Although only a single specimen of this species is known, it is 

 sufficiently distinct from N. cerussus to be regarded as a good species. Externally 

 the pattern is different, while in the genitalia the form of the uncus and the shape of 

 the elongate transtilla separate cerussus from mysticus. This species is also described 

 because it is only the second known species in the genus, which appears to be a 

 development of Chrysotypus. 



Distribution. Map 4. Ivory Coast. 



Material examined. 



Holotype <J, Ivory Coast: Adiopodoume, ix.1963 (Piart & Griveaud), BM slide 

 no. 10392, in MNHN. 



PACHYTHYRINAE 



The subfamily characters are given on p. 15. Only one genus of this subfamily 

 is known from Africa. 



DYSODIA Clemens 



Dysodia Clemens, i860 : 349. Type-species, Dysodia oculatana Clemens, by monotypy. 

 Dysodia Clemens; Whalley, 1964a : 119. 

 Dysodia Clemens; Whalley, 1968 : 3. 



Since the publication of a revision of the African species of the genus (Whalley, 

 1968) additional material has been received. The additional information is in- 

 corporated in the following check-list of African species of the genus. For keys to 



