52 PROCEEDINGS OF THE NATIONAL MUSEUM vol. iis 



pronotal surface witli a shallow anterolateral depression on each side 

 and a vague central-posterior depression; pubescence fine, sparse, 

 recumbent, retrose posteriorly, yellow. Pronotal shape obovate with 

 sides convergent posteriorly, somewhat constricted posterior to the 

 center; punctation moderate, space between punctures slightly less 

 than tlie diameter of the puncture; interspaces microreticulate. 

 Scutellum pale, concolorous with pronotiun. Legs fuscus, femora pale 

 except for "knee" area; claws simple. 



Elytra fuscus; pubescence fine, reciunbent, moderate in density, 

 yellow; elytral costae evident, sutural and lateral area concolorous 

 with elytral disk; surf ace rugose-punctate, interspaces microreticulate ; 

 elytra somewhat flattened, apices rounded, sutural angles obtuse. 



Abdomen with sterna fuscus. 



Male genitalia agree with those of the genus ; penis broadly expanded 

 apically with a subapical dorsal enlargment in the area of the ejacu- 

 latory duct (fig.2c) ; internal sac with evident spicules. Paramere 

 (fig. 2d) with apical bifurcation greater than ji the length. (The 

 figures are not of the holotype, but from a specimen from Del Rio, 

 Texas). 



Body shape moderately elongate; length 9.2 mm.; head length/- 

 width ratio .8837; pronotiun length/width ratio 1.0681; elytral 

 length/width ratio 3.0476. 



Allotype: Female, same data as holotype. There is no significant 

 sexual dimorphism. Body measurements: length 10.8 mm.; head 

 length/width ratio .8958; head length/interocular distance ratio 

 1.9090; pronotum length/width ratio 1.1041; elytra length/width 

 ratio 3.000. 



Paratypes: Texas: Del Rio, Apr. 25-26, 1959, 2; Big Bend National 

 Park, Boquillas, May 17, 1959, 2; same data as holotype, 5; same 

 data as holotype except May 20, 1959, 1 ; Oak Spring, 4000 ft. May 8, 

 1959, 2; May 22, 1959, 3; Santa Elena, 3200 ft.. May 4, 1959, 2; 

 Maverick, 2700 ft., May 4, 1959, 2; Chisos Basin (pi. 4 top). May 19, 

 1959, 1; May 22, 1959, 1; May 27, 1959, 1 (afl collected by Edward 

 Becker and Henry F. Howden.) 



Additional specimens examined: In addition to the type series, the 

 following specimens are not made a part of the type series because of 

 the scarcity of specimens and the lack of data to show that they are a 

 part of the type population: Mexico: Tlahualilo, Durango, July 28, 

 1935, 1 (Texas A. and M. Univ. collection). Texas: Brownsville, 2; 

 Chisos Mts., May 10, 1949, 1 (U.S. Nat. Mus. collection); Starr Co., 

 Mar. 20, 1952, 1; Chisos Mts., May 27, 1959, 1 (Ohio State Univ. 

 collection). 



Variation: The color pattern of these beetles is rather distinctive. 

 They resemble somewhat certain populations of Xanthochroina hicolor 



