the Genua Aorus, Schh. 339 



Exarcus, Pascoe, Ann. k Mag. Nat. Hist. (5) xix. 1880, p. 372 (syn. 



nov.). — Type, A. hearseyi, Pasc. 

 Stenodema, Faust, Ent. Nachr. xi. 1885, p. 16— Type, A. castanem, 



Gerst. (=ferruyinei(s, Fst.). 



Gerstaecker assigned the genus to the Baridinge, from 

 which, however, it must be excluded owing to the structure 

 of the mesepimera; whereas Faust placed it in the ErirrhininiB, 

 and this seems the most satisfactory conclusion. 



Key to the Species of Aorus. 



1 (14). Second joint of front tarsi as broad as or 



broader than long ; prothorax coarsely 

 punctate at the sides. 



2 (5). Prothorax coarsely punctate throughout ; 



intervals of elytra each with a single 

 row of distinct widely spaced punc- 

 tures. 



3 (4). Punctures on the prothorax much broader 



than the interspaces between them ; 

 punctures in the striae of the elytra 

 subquadrate and as broad as or 

 broader than the intervals spadiceus, Gyl. 



4 (3). Punctures on the prothorax narrower 



than the interspaces ; punctures on 

 the elytra round and narrower than 

 the intervals , castaneus, Gerst. 



5 (2). Prothorax finely punctate on the disk 



and much more coarsely so at the sides 

 and base ; intervals of elytra impunc- 

 tate or with minute irregular punc- 

 tures. 



(! (13). Prothorax not or but very slightly 

 broader than long ; length 7-10 mm. 



t (10). Form more elongate, the elytra nearly 

 three times as long as the prothorax ; 

 second joint of fuuicle longer, the 

 third as long as broad ; colour red- 

 brown. (Asiatic species.) 



8 (9). Anterior tibiae with a very strong an- 



gular process internally in the middle, 

 bearing a. tooth that is directed ob- 

 liquely forwards; the width of the 

 tibia to the tip of this tooth as great 

 as at the apex including the uncus ; 

 the basal external angles of the elytra 

 acute hearseyi, Pasc. 



9 (8). Anterior tibiae only slightly and roundly 



produced internally, the teeth small, 

 vertical, and not projecting more than 

 half as far as the apical uncus; the 

 basal external angles of the elytra 



rounded fem/yineus, Boh. 



10 (7). Form stouter, the elytra only a little 



25* 



