170 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. Ill 



Lepturoides fulvus (Motschulsky) ( ?) : Only one larva was ex- 

 amined. This specimen was from Alaska and the identification was 

 made entirely on the basis of locality. (U.S.N.M.) 



Genus ATHOUS Eschscholtz 1* 



Figures 12, a, c ; 34-36 



Larvae of 14 species of Athous have been studied. These are pri- 

 marily forest forms, living in the litter and decaying wood, and 

 probably are chiefly predaceous. A few European species are found 

 in woodland meadows and cause injury to plants when such areas 

 are brought under cultivation. Larvae of this genus have not been 

 recorded as crop pests in North America. 



In America, Athous larvae collected in May and June frequently 

 have pupated within a few days after being brought indoors. These 

 findings suggest that some species of Athous normally transform to 

 adults in June or early July. However, with species of the vittatus 

 group, pupation is reported to occur in late July and August and the 

 adults overwinter in their pupal chambers. Very little is known about 

 the duration of larval life; for A. haemorrhoidalis (Fabricius), 

 Roberts (1922, p. 316) suggests 3 or 4 years; for the common 

 American species, there is evidence that indicates a shorter life 

 cycle. 



The undivided prosternum {prst, fig. 31, c), places Athous near 

 Hemicrepidius, Lepturoides, Elathous, Limonius, and certain species 

 of Ludius. Generic distinction is most readily obtained if the larvae 

 of Athous are considered in two artificial groups as follows : Group I, 

 caudal notch large (figs. 34, h; 35, c; 36, a) ; eyes present. Group II, 

 caudal notch small (fig. 34, c, d) ; outer prongs of urogomphi much 

 longer than inner prongs ; dorsum yellow or yellowish brown. Group I 

 resembles the larvae of Hemicrepidius, but is distinguished by the 

 presence of eyes. Group II differs from Lepturoides larvae in color, 

 and from the larvae of Elathous, Limonius, and allied Ludius by the 

 long outer prongs. Larvae with large, deep pits or prominent trans- 

 verse rugae on the abdominal mediotergites (figs. 34, e; 35, e; 36, c ; 

 37, h) are either Athous or Hemicrepidius, depending upon the pres- 

 ence or absence of eyes. The Asiatic Pleonomus has been reported 

 by Ghilarov (1937, p. 635) as inseparable in the larval stage from 

 the European Athous, but specimens were not available for examina- 

 tion in the present study. 



^* On the basis of larval characters the European Athous niger (Linnaeus) 

 and a larva believed to be Athous hirtus (Herbst) are typical Hemicrepidius and 

 are discussed under that genus. 



