Orchestomerus

Yoshitake, Hiraku & Anderson, Robert S., 2015, A Review Of The Genus Orchestomerus Dietz (Coleoptera: Curculionidae: Ceutorhynchinae: Cnemogonini) Of The Usa, The Coleopterists Bulletin 69 (4), pp. 565-578 : 576-577

KEY TO THE SPECIES OF ORCHESTOMERUS

IN THE USA

1. Body mostly covered with narrow scales, which are truncate apically. Median paired prominences on pronotum ridged................2

1′. Body mostly covered with hair-like to linear scales, which are narrowed apically. Median paired prominences on pronotum not ridged...................................................................3

2. Ridges on median paired prominences on pronotum sharp. Male mid-tibiae mucronate, hind tibiae not mucronate in either sex. Lateral impressions on abdominal ventrite 5 shallower. Median impression on male abdominal ventrite 5 smaller, covered with oval to elliptic scales. Aedeagus with apical setae and lacking broad laminate apical projection ..................... ..................................................... O. wickhami

2′. Ridges on median paired prominences on pronotum obtuse. Male mid- and hind tibiae mucronate. Lateral impressions on abdominal ventrite 5 deeper. Median impression on male abdominal ventrite 5 larger, covered with lanceolate to acicular scales. Aedeagus with broad laminate apical projection and lacking apical setae.................. O. eisemani

3. Body mostly black. Prothorax roundly narrowing from middle to subapical calli. Median paired prominences on pronotum weak and obtuse. Elytral intervals mostly minutely granuate. Sides of elytra definitely bisinuate on basal half of each side. Mid- and hind tibiae mucronate in males ...................... O. marionis

3′. Body mostly dark brown. Prothorax with sides narrowing straight from middle to subapical calli. Median paired prominences on pronotum stronger and sharper. Elytral intervals with larger and sharper granules. Sides of elytra hardly bisinuate on basal half of each side. Mid-tibiae mucronate in males, hind tibiae not mucronate in either sex............... O. whiteheadi