56 R. W. CROSSKEY 



Helena). Nothing is yet known of the biology of S. atlanticum but morphological 

 features of the female suggest that the species is haematophagous, ornithophilic and 

 anautogenous. 



Subgenus EUSIMULIUM Roubaud 



Eusimulium Roubaud, 1906 : 521. Type-species : Simulia aurea Fries, 1824, by monotypy. 

 (As subgenus of Simulium Latreille, 1 802) . 



Cnetha Enderlein, 1921 : 199. Type-species : Atractocera latipes Meigen, 1804, by original 

 designation. 



Nevermannia Enderlein, 1 92 1 : 199. Type-species : Simulium annulipes Becker, 1908 [ = Simul- 

 ium ruficorne Macquart, 1838], by original designation. 



Stilboplax Enderlein, 1921 : 199. Type-species : Simulium speculiventris Enderlein, 1914, by 

 original designation. 



Friesia Enderlein, 1922 : 69. Type-species : Nevermannia tristrigata Enderlein, 1921, by 

 original designation. 



Pseudonevermannia Baranov, 1926 : 164. Type-species : Atractocera latipes Meigen, 1804, by 

 original designation. (As subgenus of Nevermannia Enderlein, 1921). Junior objective syn- 

 onym of Cnetha Enderlein, 1921. 



Ckelo cnetha Enderlein, 1936a : 117. Type-species : Chelocnetha biroi Enderlein, 1936 [ = Simul- 

 ium ornatipes Skuse, 1890], by original designation. 



Cryptectemnia Enderlein, 1936a : 114. Type-species : Cryptectemnia laticalx Enderlein, 1936 

 [preoccupied in Simulium by laticalx Enderlein, 1934, =orsovae Smart, 1944, replacement 

 name], by original designation. 



Miodasia Enderlein, 19366 : 39. Type-species : Miodasia opalinipennis Enderlein, 1936, by 

 original designation. 



Diagnosis, $? : Basal section of radius haired. Pleural membrane bare. Katepisternum 

 bare (a few exceptions in aureum-group and latipes -group) . Fore tarsus slender, fore basitarsus 

 about 6-8 times as long as its greatest breadth. 9 : cibarium unarmed (rarely few minute 

 denticles) . Tarsal claws almost always with very large basal tooth, rarely basal tooth small and 

 pointed or reduced to inconspicuous blunt spinule, very rarely absent altogether. Scutum 

 without silver-grey anterior pattern or definite dark vittae. Abdomen evenly covered with 

 pale scales. Seventh sternite sometimes well developed. Gonapophyses simple bluntly 

 rounded or truncate lobes. Paraprocts normal. Spermatheca often with conspicuous reticulate 

 pattern, without internal hairs, q* : scutum without definite pattern. Genitalia with styles of 

 varied form, usually broad and truncate or large and tapering and a little shorter than coxite, 

 sometimes as long as coxite, in aureum-gvoup very small in relation to coxites and with angular 

 twist ; style with one apical spinule ; coxite not produced beyond base of style ; ventral plate 

 not toothed, nearly always in form of large transverse plate with haired median keel and short 

 forwardly-directed basal arms, in aureum-group small and elongate-triangular with very large 

 widely divergent and outwardly directed basal arms ; median sclerite normally narrow and 

 elongate, sometimes bifurcate with splayed ends, rarely short and broad ; parameres of varied 

 form, usually of hinged type with one very large parameral hook and one or two small secondary 

 hooks at base of main hook, in some forms numerous strong subequal hooks. Pupa : Gill 

 usually with four long sinuous filaments directed mainly forwards, filaments sometimes divergent 

 or thickened basally, very rarely the four filaments arising from long thick trunks, one or two of 

 the filaments sometimes reduced thumb-like or lost completely so that gill has three filaments ; 

 gill in some forms with 6-14 filaments ; gill typically as long as or longer than body of pupa. 

 Abdomen with normal onchotaxy, sometimes with supernumerary pair of hooks each side 

 ventrally on segment 4 and sometimes with row of four small hooklets each side dorsally on seg- 

 ment 2 ; abdominal segments 6-8 (sometimes only 7 and 8) dorsally with spine-combs. Cocoon 



