OEDEMERIDAE FROM TEXAS — ARNETT 49 



9. General color reddish orange, elytra stained at base with piceus to entirely 

 piceus; mandibles usually large; pronotum distinctly marked with centi'al 

 piceus stripe, and a piceus patch on each side. 



Oxacis trimaculata Champion 



Elytra purple piceus, often with very narrow pale sutural and marginal stripe, 



rarely with vague submarginal pale stripe; pronotum orange, usually with 



piceus markings Oxacis cana (LeConte) 



The folloAving list of Big Bend National Park species is complete 

 as of this writing. Although other collections have been made in 

 the Park previously and since, including collections made by the 

 author, only one additional species has been taken which was not 

 collected by Howden and Becker. Only this additional record is 

 included. No doubt additional collecting at other times during the 

 season will reveal stUl more species. 



No extensive ecological characterization of the area has been made. 

 Webb (1950) and others (e.g., Peterson, 1960) refer to the area as the 

 Trans-Pecos community which corresponds to Dice's (1943) 

 Chihuahuan Biotic province. Plant succession in the area has been 

 described to some extent by Muller (1940). Some of the more 

 striking plants are described in McDougall and Sperry (1951). The 

 geology of the region is reported by Udden (1907). Howden (1960) 

 has published a map of the area, which is reproduced here, and a list 

 of the Scarabaeidae. All of the Big Bend National Park localities 

 mentioned in the following discussion are located on this map (fig. 1). 



Sparedrus depressus (Champion) 



This species was taken at Chisos Basin May 1-8 by beating gray 

 oak and at light. At Tornillo Flat specimens were taken on May 12 

 by beating Acacia species. This is the first record of the species in 

 the United States. 



The species was described from a single male specimen taken at 

 Mexico City. It has not been again reported until this collection of 

 13 specimens. As in other species of this genus, the fifth visible 

 sternum of the male is deeply emarginate in contrast to the slightly 

 emarginate condition in the female. 



Vasaces elongatus Amett 



The type locality of V. elongatus is Chisos Basin (pi. 1, top). Until 

 this collection of six specimens, the species was known only from the 

 female holotype. The specimens reported here were collected at 

 light between May 23 and 29. The description of the male follows: 



Male: Chisos Basin, Big Bend National Park, Tex., May 29, 1959 

 (collected by Howden and Becker). The male agrees with the 

 female holotype except as follows: front of head coarsely punctate, 

 depressed somewhat behind antennae. Pronotum longer than broad 



