SMICRONYX WEEVILS—ANDERSON 238 
SMICRONYX INSTABILIS GROUP 
Description: Body oblong ovate, moderately stout (fig. 13). 
Rostrum stout, moderately curved (figs. 14-15), usually faintly 
striate. Prothorax broadly rounded on the sides, narrowed and 
sometimes slightly constricted toward the apex; disk evenly, but not 
closely, punctate, closely punctulate between punctures (fig. 13). 
Elytra broadest at base, declivities usually distinct; scales evenly 
covering surface, their colors forming patterns in some species. 
Median lobe of male genitalia lightly sclerotized at middorsum; a pair 
of sclerites present on internal sac; internal sac usually not exceeding 
median lobe in length (figs. 62-66). 
Discussion: The species of this group resemble the species of the 
S. cinereus group in general body form and proportions. However, 
their prothoraxes are not as deeply punctate and shining as in the 
species of the latter group, and there are no pairs of sclerites on the 
internal sacs of the male genitalia of the species of the S. cinereus 
group, as there are in the species of the S. anstabilis group. 
Map 3 gives the distribution of this group. 
Map 3.—Distribution of the specimens examined of the instabilis group (except S. rhodopus 
Dietz) of Smicronyx. ©, S. defricans; A, S. posticus; @, instabilis; A, S. pusillus; 
®, S. languidulus; %, S. silaceus. 
