NO. II LARVAE OF THE ELATERID BEETLES GLEN 1/9 



suit that single specimens are taken and reared to adults leaving only 

 the larval exuviae for examination. Additional material and further 

 study are required for sound selection of key characters and for the 

 definition of "species groups" within the genus. 



A single larva of Hemicrepidius sp. was collected from a decaying 

 Cottonwood stump on the banks of the Old Man River at Lethbridge, 

 Alberta. Decaying wood may be the typical habitat of this species, 

 but the larvae of the other species are known to be primarily soil 

 inhabiting, preferring moist soils such as woodland meadows and 

 only rarely occurring in forest litter or in decaying wood. 



H. memnonhts (Herbst) has been reared from a New Brunswick 

 garden, and from leaf litter in Pennsylvania. However, the species is 

 recorded as far west as Alberta. H. bilobatus (Say) and H. hemipodus 

 (Say) appear to be more truly eastern, not being recorded from west 

 of the Great Lakes. 



H. hemipodus is the only species commonly encountered in the 

 larval stage. It has been taken from cornfields and other cultivated 

 or pasture land from Maine to Illinois, but apparently it does not 

 cause very severe crop injury. Forbes (1892, p. 39) suggests that 

 this may be due in part to the early date at which larval activity ceases, 

 pupation occurring normally in May or June. The newly formed 

 adults appear to leave their pupal cells immediately. Similar habits 

 of pupation and adult emergence are reported (Henriksen, 191 1, 

 p. 274) for Athous niger, and rearing records of other Hemicrepidius 

 larvae indicate that pupation normally occurs relatively early in the 

 summer. This biological character is common to Hemicrepidius, Lep- 

 turoides, several American species of Athous, and possibly Elathous. 

 However, Blatchley (1910, p. 770) reports finding adults of H. mem- 

 nonius in Indiana from June 8 to December 2y, hibernation occurring 

 beneath the bark of red oak logs. 



On the basis of larval structure, Hemicrepidius is very closely re- 

 lated to Athous. Distinction is most readily obtained through the 

 absence of eyes in Hemicrepidius. Other important characters are: 

 Dorsum yellowish brown, never dark brown ; large caudal notch ; uro- 

 gomphal prongs (fig. 37, c) subequal, or outer prongs slightly longer ; 

 abdominal mediotergites (fig. 37, b) with conspicuous transverse 

 rugae, and with impressions reaching to middorsal suture in some 

 segments. The urogomphal prongs show considerable individual varia- 

 tion ; in typical specimens each prong has a short, sharp tip, but this 

 is frequently worn away, especially on the outer prongs, giving them 

 the smooth, rounded appearance found in Athous cucullatus (Say) 

 and its allies. 



