NO. II LARVAE OF THE ELATERID BEETLES GLEN I73 



far as is known this material was not associated with reared speci- 

 mens, but the species has been reared in Europe and the material 

 available was similar to that figured by Henriksen (1911, figs. 72-74) 

 as A. subfuscus. (C.N.C. and U.S.N.M.) 



THE ATHOUS RUFIFRONS GROUP 



Figure 34, d-f 



PROVISIONAL KEY TO SPECIES 



I. Abdominal mediotergites (fig. 34, e) with coarse, conspicuous, transverse 



rugae ; central and eastern United States and Canada 2 



Abdominal mediotergites with shallow, less conspicuous rugae; along the 



coast and mountains from Alaska to California 



A, pallidipennis Mannerheim 



2.15 Urogomphi (fig. 34, d) with inner prongs (ipr) somewhat ensiform; 



usually in decaying wood, rarely in leaf litter.. A. rufifrons (Randall) 

 Urogomphi (fig. 34, /) with inner prongs (ipr) more subquadrate; 

 known only from damp decaying forest litter. . . .A. brightwelli (Kirby) 



This group is described from the larvae of three North American 

 species. Larvae of A. rufifrons have been collected in New Bruns- 

 wick, Canada, and in Minnesota, Maryland, and Delaware, but larvae 

 of A. brighhvelli have been taken only in Pennsylvania although the 

 adults are known as far west as Indiana (Blatchley, 1910, p. 759). 

 Larvae of the western A. pallidipennis are known only from Walla 

 Walla, Wash. 



These are all forest species and probably are chiefly predaceous. 

 Rearing notes for rufifrons show that larvae collected in April have 

 matured to adults in May, suggesting that the normal time of pupa- 

 tion is early summer. 



Larvae of this group are characterized by the yellow-brown color, 

 the small caudal notch, urogomphi (fig. 34, d, f) with outer prongs 

 much longer than inner prongs, and abdominal mediotergites (fig. 

 34 ^) with an abundance of transverse rugae. 



Mature larvae may exceed 20 mm. in length. Ninth abdominal 

 segment with 4 "teeth" (the most posterior "tooth" usually large and 

 sharp) on each side of dorsum, and distance between caudal notch 

 and pleural area about one-fifth to one-fourth total length of segment. 



15 The characters used for separating rufifrons and hrightivelli are entirely 

 provisional. Only larval exuviae of brightzvelli were available for examination 

 and further study of whole larvae is necessary before better key characters can 

 be given. The data on habitats probably are insufficient to serve as a basis of 

 separation. 



