Orchestes, IN

Sweeney, Jon, Anderson, Robert S., Webster, Reginald P. & Neville, Ron, 2012, First Records of Orchestes Fagi (L.) (Coleoptera: Curculionidae: Curculioninae) in North America, with a Checklist of the North American Rhamphini, The Coleopterists Bulletin 66 (4), pp. 297-304 : 302-303

KEY TO THE SPECIES OF ORCHESTES IN

NORTH AMERICA

This key is modified from that by Anderson (1989) with the addition of O. alni and O. fagi . Note that Anderson (1989) considered Rhynchaenus Reitter as the valid generic name, but recent refinements to the generic concepts in Rhamphini have resulted in a shift in placement of all these species to Orchestes ; true Rhynchaenus comprise only a few widespread species that feed on Asteraceae , none of which occur in North America. Please consult Anderson (1989) for illustrations of the important characters, which are not repeated here.

1. Scutellum with dense, white, silver-gray or yellow, broad, appressed scales that contrast with vestiture of elytra. Mesepisternum and metepisternum with scales denser and broader than on metasternum, some scales bifurcate. Larval hosts: Betulaceae ...............................2

1′. Scutellum with indistinct golden to dark brown or black, hair-like scales, similar in vestiture to elytra. Mesepisternum and metepisternum with scales similar in density and form to those on metasternum, all scales simple, hair-like. Larval hosts: Betulaceae , Ulmaceae , Rosaceae , Fagaceae ........................................ 3

2. Front and middle femora each with ventral margin with small seta set in slightly developed denticle. Eyes separated by distance of 0.35–0.60X width of eye in anterior view. Pronotum and basal part of elytra lacking laterally directed, long, erect, hair-like scales. Antenna with scape 1.05–1.45X length of article one of funicle. Larval hosts: Alnus , Betula (Betulaceae) ..... O. testaceus (Müller)

2′. Front and middle femora each with ventral margin simple, lacking spines or denticles. Eyes separated by distance of 0.20–0.40X width of eye in anterior view. Pronotum and basal part of elytra of most specimens with laterally directed, long, erect, hair-like scales on lateral margins. Antenna with scape 1.50–1.90X length of article one of funicle. Larval hosts: Alnus (Betulaceae) .................... ....................................... O. griseus (Sleeper)

3. Body color variously black and red.............4

3′. Body color entirely black.............................5

4. Elytra and abdomen vivid red. Pronotum and basal portion of elytra lacking long, erect, hair-like scales. Larval host: Betula (Betulaceae) ......................... O. betuleti Horn

4′. Elytra, pronotum, legs, and apical portion of abdomen red (may be spotted or infused with black). Pronotum and basal portion of elytra with laterally directed, long, erect, hair-like scales. Larval host: Ulmus (Ulmaceae) .......... ..................................................... O. alni (L.)

5. Head with eyes not protruding, in lateral view with profile of head evenly rounded. Vestiture of body uniformly moderately dense, golden in color. Elytra proportionally long, length of elytra 4.1–4.7X pronotal length. Larval host: Fagus (Fagaceae) ............... O. fagi (L.)

5′. Head with eyes protruding, in lateral view with profile of head distinctly swollen at eyes. Vestiture of body uniformly moderately dense, white in color (rarely golden in some specimens). Elytra proportionally more robust, length of elytra 3.3–3.7X pronotal length. Larval host: Betulaceae , Ulmaceae , Rosaceae ....................................................................6

6. Male: hind femur moderately to markedly expanded, length 2.25–2.90X maximum width; aedeagus in lateral view thin and flat, internal sac in dorsal view with “bell-shaped” sclerite at midlength and pair of coarsely setose areas anterior to, or in part underlying, median sclerite. Female: hind femur markedly expanded 2.25–2.60X maximum width; apical portion of vagina with large, median, “cone-shaped” sclerite. Larval host: Crataegus , Prunus , Pyrus , Amelanchier (Rosaceae) .......... ............................................... O. pallicornis Say

6′. Male: hind femur slightly to moderately expanded, length 2.75–3.10X maximum width; aedeagus in lateral view robust, internal sac in dorsal view with pair of elongate, slightly sinuate, dark sclerites at more or less midlength. Female: hind femur moderately to markedly expanded, length 2.30–2.95X maximum width; apical portion of vagina with anterolateral margins and median area of basal margin darkly sclerotized. Larval host: Alnus , Betula , Carpinus , Corylus (Betulaceae) ; Ulmus (Ulmaceae) ............ O. mixtus Blatchley