Geraeus picumnus (Herbst)

Prena, Jens, 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), pp. 123-172 : 150-152

Geraeus picumnus (Herbst)

( Figs. 3, 4 , 29, 30 , 71 )

Curculio picumnus Herbst 1797:30 . Described from Herschel Collection; 8 syntypes in MNHUB .

Baridius picumnus ; Say (1831).

Centrinus picumnus ; Schönherr (1844).

Geraeus picumnus ; Champion (1908); Kuschel (1983).

Centrinaspis picumnus ; Casey (1920).

Centrinus olivaceus Gyllenhal 1836:763 . Type material in NHRS; not examined. Synonymy by Gyllenhal (1836:763).

Centrinus perscillus Gyllenhal 1836:762 . Type material in NHRS; not examined. Synonymy by Kuschel (1983:38).

Geraeus perscillus ; Champion (1908).

Centrinaspis perscilla ; Casey (1920).

Centrinus sutor Harris 1836:81 . Type material not located. Synonymy by LeConte (1876:311).

Centrinus albotectus Casey 1892:582 . Syntypes, 7 males, 3 females, labeled (1) ‘‘Fla,’’ ‘‘σ,’’ ‘‘Casey/ bequest/ 1925,’’ ‘‘Type USNM/ 37827 ,’’ Casey’s handwriting ‘‘albotecta/ Csy.’’; (2–10) ‘‘Fla,’’ ‘‘Casey/ bequest/ 1925,’’ ‘‘albotectus-2 [other specimens numbered 3, 4, 5, 6, 8, 9, 10, 11]/ Paratype USNM/ 37827 ’’ (USNM). Synonymy by Kuschel (1983:37).

Geraeus albotectus ; Champion (1908).

Centrinaspis albotecta ; Casey (1920).

Centrinus lentus Faust 1896:117 . Syntypes, 1 male, 1 female, labeled ‘‘σ Caracas / E Simon.,’’ ‘‘lentus/ Faust,’’ Coll. J. Faust / Ankauf 1900,’’ ‘‘TYPE,’’ dissected (SNSD); ‘‘ Caracas / E. S.,’’ ‘‘lentus/ Faust,’’ ‘‘ Type’ ’ (SNSD). Synonymy by Kuschel (1983:37).

Centrinaspis compacta Casey 1920:399 . Holotype female, labeled ‘‘Columb/ 28.7 Tex,’’ ‘‘Casey/ bequest/ 1925,’’ ‘‘Type USNM/ 37830 ,’’ Casey’s handwriting ‘‘compacta/ Csy.’’ Paratype male, labeled ‘‘Columbus, Tex/ Wickham.,’’ ‘‘σ,’’ ‘‘Casey/ bequest/ 1925,’’ ‘‘compacta-2/ Paratype USNM/ 37830 ’’ (USNM). Synonymy by Kuschel (1983:37).

Centrinaspis floridensis Casey 1920:398 . Holotype female, labeled ‘‘Fla,’’ ‘‘Casey/ bequest/ 1925,’’ ‘‘Type USNM/ 37826 ,’’ Casey’s handwriting ‘‘floridensis/ Csy.’’ Synonymy by Kuschel (1983:37).

Centrinaspis lasciva Casey 1920:398 . Holotype female, labeled ‘‘Alpine, Tex/ July 20–22/ 4,400–6,000 ft / Wickham,’’ ‘‘Casey/ bequest/ 1925,’’ ‘‘Type USNM/ 37889 ,’’ Casey’s handwriting ‘‘lascivus/ Csy.’’ Synonymy by Kuschel (1983:37).

Centrinaspis paulula Casey 1920:399 . Syntypes, 3 males, 3 females, labeled (1) ‘‘Ariz,’’ ‘‘Casey/ bequest/ 1925,’’ ‘‘Type USNM/ 37828 ,’’ Casey’s handwriting ‘‘paululus/ Csy’’; (2–5) ‘‘Ari.,’’ ‘‘Casey/ bequest/ 1925,’’ ‘‘paulula-2 [other specimens numbered 3, 4, 5]/ Paratype USNM/ 37828 ’’; (6) ‘‘Ariz,’’ ‘‘Casey/ bequest/ 1925,’’ ‘‘paulula-6/ Paratype USNM/ 37828 ’’ (USNM). Synonymy by Kuschel (1983:38).

Centrinaspis perpusilla Casey 1920:400 . Holotype female, labeled ‘‘Columb/ 20.8 Tex,’’ ‘‘Casey/ bequest/ 1925,’’ ‘‘Type USNM/ 37831 ,’’ Casey’s handwriting ‘‘perpusillus/ Csy.’’ New synonymy.

Geraeus perpusillus ; O’Brien and Wibmer (1984).

Centrinaspis argentis Blatchley 1925:102 . Syntypes ‘‘several,’’ Crawford Co., IN (PURC), not examined. New synonymy.

Geraeus argentis ; O’Brien and Wibmer (1984).

Recognition. Geraeus picumnus is a small, 1.9–2.9 mm long species with uniform vestiture and a rather long, slender rostrum. It is common and widespread in the United States, where no other similar species occurs. In Central and South America, G. picumnus can be confused easily with G. timidus (Casey) . Male G. picumnus differ in having a ventrodistal spine on the middle tibiae, the body of the aedeagus deeply trough-shaped and its apex abruptly bent; female G. picumnus differ in having the scape not more than twice as long as the first desmomere ( Figs. 68, 69 ).

Distribution. This species occurs in the central and eastern United States ( Fig. 71 ) and reaches Canada in southern Ontario (McNamara 1991). The distribution seems to be discontinuous in the dry zones of western Texas and New Mexico. Specimens were collected throughout Central America and in Venezuela. Some of Champion’s (1908) records refer to G. timidus .

Type locality. North America , site not specified .

Material examined. United States: Alabama ( CWOB 6, USNM 352), Arizona ( CMNC 66, CWOB 57, USNM 48), Arkansas ( CMNC 1, USNM 8), Connecticut ( CWOB 1, USNM 1), Delaware ( CWOB 5, USNM 7), District of Columbia ( USNM 8), Florida ( CMNC 12, CWOB 67, USNM 47), Georgia ( CMNC 3, CWOB 10, USNM 33), Illinois ( CMNC 3, CWOB 12, USNM 53), Indiana ( USNM 3), Iowa ( USNM 1), Kansas ( CMNC 1, CWOB 13, USNM 51), Kentucky ( CMNC 1, USNM 4), Louisiana ( USNM 41), Maryland ( CMNC 3, USNM 258), Massachusetts ( BMNH 1, CMNC 1, UNSM 1, USNM 12), Michigan ( USNM 2), Mississippi ( USNM 27), Missouri ( UNSM 2, USNM 22), Nebraska ( UNSM 1), New Jersey ( BMNH 2, CWOB 1, USNM 30), New Mexico ( CWOB 1, USNM 2), New York ( CWOB 3, USNM 4), North Carolina ( BMNH 1, CMNC 27, CWOB 3, USNM 37), Ohio ( UNSM 1), Oklahoma ( CMNC 3, USNM 13), Pennsylvania ( BMNH 2, UNSM 2, USNM 22), Rhode Island ( USNM 1), South Carolina ( CMNC 10, CWOB 3, UNSM 1, USNM 64), Tennessee ( CMNC 4, USNM 12), Texas ( CMNC 58, USNM 88), Virginia ( USNM 58), West Virginia ( CMNC 3, USNM 2) Belize ( CWOB 61), Costa Rica ( USNM 2), El Salvador ( USNM 1), Honduras ( CWOB 26, USNM 11), Mexico ( CMNC 1, CWOB 5, JPPC 4, USNM 21), Nicaragua ( BMNH 1, USNM 3), Panama ( CWOB 1, USNM 11), Venezuela ( SNSD 2, USNM 2). Total 1,834 specimens.

Temporal occurrence. April to September.

Plant associations. Blatchley and Leng (1916:381) stated that G. picumnus infests the stems of foxtail grass, Chaetochloa glauca L. [5 Setaria pumila (Poir.) Roem. and Schult. ]. A handwritten note in R. Warner’s copy ( USDA, SEL) states that this observation refers to Centrinopus , which probably is based on Buchanan’s identification of specimens in the larval collection of the USNM. Despite being a common species with a wide distribution, the host plant of G. picumnus seems to be unknown.

Note. Blatchley (1922) described Centrinaspis argentis relying on Casey’s opinion, which is cited in the description. Based on the information provided in the description and specimens standing under this name in collections, I consider C. argentis a new synonym of Geraeus picumnus (Herbst) . The Blatchley material could not be accessed.

Figures

Figs. 1–8. Geraeus and Linogeraeus species, anterior portion of prosternum. 1) G. modestus, male; 2) G. modestus, female; 3) G. picumnus, male; 4) G. picumnus, female; 5) L. finitimus, male; 6) L. finitimus, female; 7) L. laevirostris, male; 8) L. urbanus, male.

Figs. 25–32. Geraeus and Linogeraeus species, dorsal and lateral aspects; scale bar 1 mm. 25, 26) G. minor, male; 27, 28) G. petilior, male; 29, 30) G. picumnus, male; 31, 32) L. crucifer, male.

Figs. 71–72. Map of United States (without northwestern part) and Central America showing distributions of G. coarctatus, G. modestus, G. penicillus, and G. picumnus.

Figs. 61–70. Geraeus and Linogeraeus species; 61–63, aedeagus, dorsal aspect of apical portion; 64–67, rostrum, dorsal aspect; 68–70, antenna. 61) L. finitimus; 62) L. neglectus; 63) L. tonsilis; 64) L. finitimus, male; 65) L. finitimus, female; 66) L. neglectus, male; 67) L. neglectus, female; 68) G. picumnus, female; 69) G. timidus, female; 70) L. capillatus, female.