137 
1975 ] Lawrence Stephan — Cerylonidae 
Key to the Genera of North American Cerylonidae 
1. Frontoclypeal suture present; terminal segment of maxillary palp 
at least 2 X as long as and more than 0.5 X as wide as segment 
3, which is shorter than or subequal to segment 2; last ventrite 
not or very finely crenulate 2 
— Frontoclypeal suture absent; terminal segment of maxillary palp 
aciculate, shorter than and less than 0.5 X as wide as segment 3, 
which is longer than segment 2; apex of last ventrite always 
strongly crenulate ( fig. 1). 7 
2. Procoxal cavities closed behind; length at least 2 mm.; body oval 
and highly convex, with smooth, even, lateral edges and no 
antennal cavities Hypodacne LeConte 
— Procoxal cavities open behind; length less than 1.5 mm.; with- 
out other characters in combination. 3 
3. Prothorax without antennal cavities; lateral edges of pronotum 
crenulate or serrate; metasternum and first ventrite without 
femoral lines; tarsi 3-segmented; body more elongate, TL/EW 
more than 1.75 4 
— Prothorax with antennal cavities; lateral edges of pronotum 
smooth; metasternum and first ventrite with femoral lines; tarsi 
4-segmented; body round or oval in outline, TL/EW less than 
1-75 5 
4. Lateral margins of pronotum crenulate ; eyes absent ; body elon- 
gate, TL/EW about 2.5 ; elytra with 7 rows of punctures bear- 
ing very short, fine hairs; procoxal cavities very narrowly sep- 
arated, the intercoxal process depressed and less than 0.2 X a 
coxal width. Anommatus Wesmael 
— Lateral margins of pronotum serrate; eyes present; body oblong, 
TL/EW less than 2.0; elytra with 10 rows of punctures bear- 
ing longer, suberect hairs; procoxal cavities more widely sep- 
arated, the intercoxal process not depressed and at least as wide 
as one coxa. Ostomopsis Scott 
5. Antennal cavities of prothorax dorsal, easily visible from above 
(fig. 21); antennae 10-segmented ; body strongly convex and 
elytral punctation seriate. Murmidius Leach 
— Antennal cavities of prothorax ventral, not visible from above; 
antennae with less than 10 segments; body flattened or elytral 
punctation confused. 6 
6. Body distinctly flattened; antennae 9-segmented; elytral punc- 
tation seriate; mesosternum truncate anteriorly; metasternal su- 
ture present. Mychocerus Erichson 
