A review of the species of Geraeus Pascoe and Linogeraeus Casey found in the continental United States (Coleoptera: Curculionidae: Baridinae)

Authors: Prena, Jens

Submitted to: The Coleopterists Bulletin
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/18/2009
Publication Date: 6/24/2009
Citation: Prena, J. 2009. A review of the species of Geraeus Pascoe and Linogeraeus Casey found in the continental United States (Coleoptera: Curculionidae: Baridinae). The Coleopterists Bulletin. 63(2):123-172.

Interpretive Summary: Weevils are one of the largest families of beetles with many agricultural pest species that cause millions of dollars in damage yearly. The present paper reviews the U.S. fauna of a very diverse group of New World weevils, which includes numerous species considered as agricultural pests, for example, on corn and its relatives. A total of 21 species is recognized, ten of them representing new U.S. records. The majority of the latter species had been collected over 80 years ago and some are not native. The lack of taxonomic expertise in the U.S. hampered the monitoring of introductions, the distinction between native and exotic species, and between agriculturally detrimental and benign species. This study will be of interest to scientists and action agencies that need to identify weevils.

Technical Abstract: The baridine weevils with a smooth inner mandibular face and unmodified antenna are reviewed for the continental U.S. Toxeres Germar 1829, a new synonym of Geraeus Pascoe 1889, is suppressed as nomen oblitum and Geraeus is conserved as nomen protectum. Pycnogeraeus Casey 1920 is a new synonym of Geraeus; Pachygeraeus Casey 1920 is a new synonym of Linogeraeus Casey 1920. Ten species of Geraeus and 11 species of Linogeraeus are recognized in the study area. Geraeus coarctatus Champion, G. nimbatus (Casey), Linogeraeus crucifer (Champion), L. squamirostris (Champion), L. tonsilis (Boheman), and L. urbanus (Boheman) represent new U.S. records. Geraeus minor Prena, G. pannuceus Prena, G. petilior Prena, and Linogeraeus appalachensis Prena are described as new species. Several species appear to have been dispersed by man since the early 1900s, but lack of taxonomic expertise prevented the systematic monitoring of their range expansions. New combinations are Linogeraeus crucifer (Champion), L. squamirostris (Champion), L. tonsus (Champion), and Oligolochus bracatoides (Blatchley) (all from Geraeus). The following new synonymies are proposed: Geraeus modestus (Boheman) (= Centrinus striatirostris LeConte, C. tortuosus Casey); G. penicillus (Herbst) (= Balaninus pistor Germar, Centrinus dilectus Harris, Centrinaspis tomentosa Casey, C. rhomboida Blatchley); G. picumnus (Herbst) (= Centrinaspis perpusilla Casey, C. argentis Blatchley); Linogeraeus capillatus (LeConte) (= Centrinus clientulus Casey, Geraeus submaculatus Champion, G. puerulus Champion, Centrinaspis repens Casey, C. segregans Casey, C. hilaris Casey); L. crucifer (Champion) (= Geraeus octomaculatus Champion); L. finitimus (Casey) (= Centrinus clarescens Casey, Centrinaspis aequalis Casey, C. furtiva Casey, C. debilis Casey, C. nacta Casey, C. profecta Casey, C. tenuicula Casey); L. laevirostris (LeConte) (= Centrinus punctirostris LeConte, Pachygeraeus aesopus Casey); and L. neglectus (Casey) (= Centrinus grisescens Casey, Centrinaspis proxima Casey, C. vitula Casey). Lectotypes are designated for Centrinus capillatus LeConte, C. neglectus LeConte, Geraeus puerulus Champion, and G. submaculatus Champion. Habitus images, maps of distribution, and a key for identification are provided.