SMICRONYX WEEVILS—-ANDERSON 243 
Smicronyx silaceus Casey 
Ficure 65 
Smicronyz silaceus Casey, Ann. New York Acad. Sci., vol. 6, pp. 392, 393, 1892. 
Lectotype, here designated: Male, Arizona, USNM 36704 (T. L. Casey 
collection). 
Description: Rostra of both sexes moderately curved, black, sub- 
striate dorsally, thinly squamose from base to shortly before antennal 
insertions; finely punctate from base to apex; shining before the 
antennal insertions. Head black, finely alutaceous, densely squamose 
above base of rostrum. Antennae piceous throughout. Prothorax 
black, moderately rounded at sides, moderately narrowed and slightly 
constricted near apex; disk sparsely but evenly covered with shallow 
rounded punctures, interspaces densely punctulate; scales pale to 
medium yellowish brown, or white, elongate or ovate, sparse, mostly 
elongate on disk except along midline; prosternum moderately emar- 
ginate and concave. 
Elytra black; intervals closely covered with ovate, subtruncate, 
white, pale yellow, or medium yellowish brown scales; dark scales 
arranged in an irregular, blotchy pattern; setiform scales of each inter- 
val a medium brown. Femora moderately clavate, rufopiceous, cov- 
ered with elliptical and elongate white scales. Tibiae piceous, cov- 
ered with elongate white scales. Tarsi piceous, third segment 
distinctly broader than first two; fourth segment extending consider- 
ably beyond third; claws nearly parallel, connate for approximately 
half their length. Sides of median lobe of male genitalia nearly par- 
allel; internal sac covered with fine spines (fig. 65). 
MeaAsuREMENTs: The following measurements were taken from 1 
male and 4 females from Tucson, Ariz. (USNM), 1 male from Catalina 
Springs, Ariz. (USNM), 1 male from Mesa, Ariz. (USNM), 2 males 
and 2 females from El Paso Co., Tex. (USNM), and 1 female from 
Laredo, Tex. (USNM). All measurements are in millimeters: 
Males Females 
Mean Extremes Mean Extremes 
Body length 1. 52 1.50-1.60 1.65 1. 50-1. 80 
Elytra length 0. 95 0.90--1.00 1.10 1. 00-1. 20 
Elytra width at base 0. 59 0. 50-0. 66 0. 65 0. 60-0. 73 
Prothorax length 0. 42 0. 40-0.48 0. 45 0. 43-0. 53 
Prothorax width 0. 45 0. 43-0.48 0. 49 0. 46-0. 56 
Rostrum length 0. 51 0. 50-0.56 0.61 0. 56-0. 66 
Rostrum length before antennal 0.17 0.16-0.20 0. 23 0. 20-0. 26 
insertion 
Funicular segment 2 length 0. 034 0. 034 
Funicular segment 3 length 0. 034 0. 034 
Broutocy: At present, no information is available on the biology of 
this species. 
