Scullen groups for Cerceris

 

 

Key groups for females from the Review of the Genus Cerceris In America North of Mexico, Herman A. Scullen 1965. Amazingly only one species in this genus in the east has been defined since Scullen's paper (C. nitoides). He grouped the females and males into five subgroups for his key with characters as noted below.  Note that females without a group were in the first portion of the key and did not fit his divisions well apparently.

 

Group I

a) small size

b) very dark stigma

c) punctation usually very crowded

d) anterior abdominal segments and propodeum often more or less reddish

e) mandibles of females with two denticles

f) mesosternal tubercle on the female

g) small and widely separated hair lobes on the male

h) apical segment of the antenna normal in the male

 

 

Group II

a) there is no prominent elevation on the surface of the medial lobe of the clypeus; however two small papilliform structures are just above the clypeal border

b) the second abdominal segment is much broader than the first, especially noticeable on the female

c) the mesosternal tubercle is absent from both sexes

d) the terminal segment of the male antenna is distorted slightly

e) the males have relatively inconspicous denticles on the clypeal border or none at all

f) the male hair lobes are normal in width

g) Buprestidae are used as prey

 

Group III

a) a distinct lamella or lamellae appears on the free margin of the medial clypeal process

b) the extension of the medial clypeal lobe on the male is noticeably narrow, with three or more less distinct denticles on its margin

c) mesosternal tubercles are absent from both sexes or are very small

d) the terminal segment of the male antenna is distorted slightly

e) Chrysomelidae are used as prey

 

Group IV

a) the females have a prominent cone-shaped process on the medial clypeal lobe, which is flanked on each side by a much smaller process attached to the lateral clypeal lobe

b) the males have the medial denticle on the clypeal margin bicuspidate

c) the pygidium of the male is very broad, almost oval

d) the hair lobes of the male are very broad, almost meeting medially

e) Tenebrionidae are used as prey

 

Group V

a) the females have a low cone-like clypeal elevation, which may be reduced to little more than a pronounced convex surface

b) the hair lobes of the male are very broad, almost meeting medially

c) the male pygidium is much longer than broad

d) there are no known prey records for this group (at the time of the paper's publication)