1975] 
Lawrence & Stephan — Cerylonidae 
157 
Cerylon Latreille 
Cerylon Latreille, 1802: 228. Type species, by subsequent monotypy (La- 
treille, 1810: 431), Lyctus histeroides Fabricius. 
Aphardion Gozis, 1886: 11. 
This genus is distinguished by the broadly closed procoxal cavities 
and apically expanded prosternal process (fig. io) and by the io- 
segmented antennae with a I -segmented club. In addition, the body 
is usually elongate and more or less parallel-sided, and the tegmen is 
reduced to a small ring at the base of the median lobe (figs. 13-14). 
Although the mouthparts in Cerylon are less modified than in Philo- 
therrnus or Lapethus, the elongate, rigid body form, with complete 
posterior coxal closure, the extremely reduced tegmen, and the highly 
modified larval head all appear to be derived characters. There are 
about 75 species, but a number of them may have to be transferred 
to other genera with further study. The majority of species occur in 
the Holarctic, Ethiopian, and Oriental regions, while the group is 
poorly represented in the New World tropics and Australia. In 
North America, the genus is represented by two widely distributed, 
primarily northern and eastern species, and three western endemics. 
Key to the North American Cerylon 
1. Intercoxal process of mesosternum twice as wide as a mesocoxal 
cavity; prosternal process slightly concave; basal impressions of 
pronotum large and distinct; clypeus shallowly emarginate in 
both sexes; Arizona. d is tans, n. sp. 
— Intercoxal process of mesosternum barely wider than a mesocoxal 
cavity; prosternal process flat or slightly convex; basal pronotal 
impressions obscure or absent. 2 
2. Elytra! vestiture distinct, easily visible at 10 X magnification; 
size larger, length usually 3.0 mm. or more; elytral intervals 
flat or slightly convex; clypeus deeply notched in male; Cali- 
fornia calif ornicum Casey 
— Elytral vestiture consisting of very short hairs, which are barely 
visible at 50 X magnification; size smaller, length usually less 
than 2.7 mm. 3 
3. Sides of pronotum (figs. 18-19) subparallel or slightly diverging 
for three- fifths of their lengths, strongly converging apically; 
antennal segment 3 more than 1.5 X as long as 4; body less 
elongate, TL/EW usually less than 2.42 ; clypeus shallowly 
emarginate in both sexes; widespread in the east and on the 
Pacific coast. unicolor (Ziegler) 
