1 62 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. Ill 



LIMONIUS CONFUSUS LeConte (?) 



A few larvae of this species have been collected at Urbana and Dan- 

 ville, 111., and at Arnprior, Ontario. This is a typical forest species, 

 the larvae occurring in decaying wood and in moist, well-decayed leaf 

 litter. 



The identity of these larvae is unknown, but it is most likely to be 

 either L. coufusus LeConte or a closely allied species. W. J. Brown, 

 of Ottawa, informs the writer that coufusus LeConte is found in the 

 woods and is the most common Limonius at Arnprior. Blatchley 

 (1910, p. 758) reports that the adults of confusus are found beneath 

 the bark of oak and other trees, but that the species is scarce in 

 Indiana. 



It is possible that there is some error in the reference by J. J. Davis 

 (1911, p. 251) to L. confusus larvae damaging truck crops in Illinois. 

 I have examined the larval exuvium of a specimen collected by 

 Mr. Davis, the reared adult of which was identified by J. A. Hyslop 

 as Limonius confusus LeConte. This larval skin bears structures of 

 great similarity to those of the larva of L. dubitans LeConte, and on 

 this basis Mr. Davis' species would be placed in the caniis group, which 

 includes L. canus and L. dubitans and their close allies. However, 

 Mr. Brown, of Ottawa, informs me that, on the basis of adult char- 

 acters, confusus and dubitans belong in distinct species groups. 

 Blatchley (1910, p. 762) states that L. dubitans "resembles so closely 

 Limonius griscus that it can with difficulty be separated." Both of 

 these species occur commonly in Indiana and undoubtedly in Illinois. 

 Davis' larva is more likely to be one of these soil-inhabiting species 

 than the woodland confusus. It is unfortunate that the adults reared 

 by Mr. Davis are either lost or misplaced and Mr. Hyslop's original 

 identification cannot be checked. 



The larva which is provisionally named confusus LeConte in the 

 present study belongs to that group of Liinonius that have very small 

 outer urogomphal prongs. Its other chief characteristics are the 

 presence of a mediodorsal groove on the ninth abdominal segment ; 

 prominent setae unpaired on abdominal mediotergites ; eyes present ; 

 and paranasal lobes without a definite cluster of pores. 



The largest larva examined measured 18 mm. in length. The ninth 

 abdominal segment bears 2 very small (inconspicuous) setae anteriorly 

 on dorsal plate ; small, blunt "teeth" on lateral aspect of dorsum ; and 

 distance between caudal notch and pleural area approximates one-fifth 

 total length of segment, exclusive of urogomphi. Nasale with tip 



