Genera and Sj^ecies of Tabanidae. 29 



Tubaniis xanthumtlas, nom. uov., for 



Tabtmus leuca.*pis, \. d. Wiilp, 'Notes from the Leyden Museum,' 

 Vol. vii. p. 74, pi. o. tifr. 3 (l8fto) (tiec Wiedemann, 1828) — nomen 

 bis lectum. 



^faterial received from various parts of Africa during the 

 last two years shows tliat Tabanus leucaspis, v. d. Wulp [nee 

 Wied.), which was formerly considered by the present 

 writer to be identical with T. pluto, Walk.*, is after all 

 distinct from that species. The name leucaspis having 

 previously been employed by AViedemann for a Tabanus 

 from I^razil, the designation of van dcr AA ulp's species must 

 be changed. 



Tabanus xanthomelas can be distinguished from T. pluto, 

 Walk., by its abdominal markings. In the case of the 

 former species, the yellowish area, clothed with chrome- 

 yellow hairs, on each side of the dorsal surface of the 

 abdomen terminates abruptly on the hind margin of the 

 tbird segment, while in that of the latter the corresponding 

 area is continued on to the fourth segment, usually as 

 far as the hind margin, and sometimes even extends on 

 to the fifth segment. In T. pluto, too, the black median 

 longitudinal stripe separating the two yellow areas is much 

 broader and has sharply defined edges, -while in T. .vantho- 

 melas the intervening stripe is less than half the width of 

 that in T. pluto, besides being more or less ill-defined and 

 incomplete, the areas clothed with chrome-yellow or Xaples- 

 yellow hair having a marked tendency to fuse together. In 

 fact, in well-preserved specimens of T. xanthomelas, the 

 median stripe may be reduced to a triangular or elongate 

 black spot on the hind margins of the second and third 

 segments, or even to a single spot on the hind margin of 

 the former segment. 



Tabanus xanthomelas, the type of which -was stated to be 

 from the Gold Coast, is represented in the National Col- 

 lection by specimens from Portuguese Congo, the Congo 

 Free State, the Anglo-Egyptian Sudan (^lougalla Province), 

 and the Uganda and Nyasaland Protectorates, Tabanus 

 pluto, Walk., the Museum examples of which are from Sierra 

 Leone and the Sierra Leone Protectorate, Liberia, and 

 Xortheru and Southern Nigeria, would, so far as present 

 knowledge goes, appear to be purely West African. 



* Cf. Austen, ' Illustrations of African Blood-sucking Flies/ p. 92 

 (lt>09). 



