September, 191fi. ) 193 



STUDIES IN HELOPHORINI. 



BY D. SHARP, M.A., F.B.S. 



(PLATES III— VI.) 



U.—ATRACTHELOPHORUS and CYPHELOPHORUS. 



Atracthelophorus Kuw. 



Although the character of the shape of the palpus appears hut. a 

 slight one, I believe AfractJielophorus to be a natural genus. The 

 labial palpi always have a comparatively small terminal joint, the 

 epipleuron is usually smaller than in Helophortis, the hind tarsi are 

 shorter and more rigid, and the flexile hairs on both thorax and legs 

 are always much reduced and very difficult to detect. The elytra are 

 always impressed, and the flanks visible beneath. All the flelophorini 

 are but imperfectly aquatic, and I believe that the species of Atract- 

 helophorns are even less aquatic than those of Helophorus. In fact 

 they haunt the neighbourhood of water, but only occasionally enter it. 

 A. hrevipalpis is, however, more closely similar in habits to Heloptlnnts 

 than the other species of the genus. A. glacialis is, on the whole, the 

 species that comes nearest to H eloplwrus ; while the Helophorus that 

 most approaches Atradhelnphorus is H. corsicanus. If Deville's 

 H. imncticolUs be really corsicanus as he states it to be, it would 

 seem that corsicanus and glacialis are found together in Corsica. 



The species are much easier of distinction than those of the genus 

 HelopJior^ts. As regards the position of the genus, cf. Cyphelophorvs. 



1. — Atracthelophorvs hrevipalpis Bedel. 



This abundant species is very variable. Lenprth 2^-3^ mm. Thorax 

 usually brilliant, always metallic, coppery, sometimes purple-metallic with the 

 grooves coppery ; sculptiire rather coarse, grantilar, even on the median 

 intervals ; sides not much outstanding, a little sinuate and slightly narrowed 

 behind, sometimes narrowly yellow. Elytra testaceous, maculate with black 

 in a very variable manner ; punctuation coarse, but variable, interstices usually 

 narrow and but slightly elevated. Legs yellow, tarsi generally a little darker 

 at the extremity, and less flexible than in most of the species of Helophorits. 

 Aedeagus (fig. 63) short and broad, the lateral lobes a little sinuate externally, 

 the struts short. In some individuals the aedeagus is distinctly narrower 

 than normal. 



Very narrow and very broad individuals are found in this species. The 

 most remarkable variety is the var. hulbipalpis of Kuwert, which occui's 

 occasionally on the banks of the rivers of Scotland ; it is of very pale colour, 

 and the terminal joint of the palpi is unusually broad and short. This variety 

 is connected with more ordinary forms by numerous aberrations. 



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