1940] 
The Genus Echestypus 
87 
is incomplete; other veins are indicated by depressed (con- 
cave) lines; only one cross-vein, between the supposed third 
and fifth longitudinals, therefore probably a fusion of an- 
terior basal cross-vein (M 3 ), anterior cross-vein (r-m) and 
portion of fourth longitudinal (M ) ; the third longi- 
tudinal ends in the tip of the costa at an acute angle and 
without knob-like swelling; the costa is thickened only at 
the extreme base and between the tips of the first and third 
longitudinals. The alula is rudimentary; the halter well 
developed and shaped as in Lipoptena. The membrane bears 
uniformly scattered, exceedingly minute microtrichia. 
It may be noted that the external morphology is extremely 
similar to that of the European Lipoptena cervi (Linnaeus) 
and the Cingalese L. efovea (Speiser), particularly in the 
arrangement of the sclerites of the abdomen and in the 
venation of the wing. 
Echestypus is known at present only from the Ethiopian 
portion of the African continent (south of the Tropic of 
Cancer), where it occurs on various antelopes, viz., on bush- 
buck and nyala (Tragelaphus) , reedbuck (Redunca) , oribi 
(Ourebia) , waterbuck ( Kobus ), duiker ( Cephalophus and 
Sylvicapra) , steinbok (Raphicerus) , springbok (Antidor- 
cas ) and kudu (Strepsiceros) . The host relationships are 
more fully discussed under each species. 1 
To some extent Echestypus is the Ethiopian representa- 
tive of Lipoptena, although I have seen a true species of 
Lipoptena (with well-developed ocelli) off bushbuck and 
duiker in Uganda and the eastern Belgian Congo. 
Four “species” of Echestypus have been described; but, 
after studying some 600 specimens, from 90 different lots 
and off more than a dozen hosts, collected throughout tropi- 
cal and South Africa, I am able to recognize three species 
only. These are, moreover, very similar, as will be seen 
from the subjoined key. As I was unable to examine the 
types of the four described forms and as the original descrip- 
tions are scattered and inaccessible to the average entomolo- 
gist, I have reproduced them in full. 
1 Throughout this paper the nomenclature of the hosts is that of 
Glover M. Allen’s recent “Checklist of African Mammals” (1939, Bull. 
Mus. Comp. Zool., LXXXIII) . 
