12 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 123 



Triplax mesosternalis Schaeffer 



Triplax mesosternalis Schaeffer, 1905, p. 145. 

 Triplax monostigma Casey, 1916, p. 1G5. 

 Triplax coloradana Casey, 1924, p. 179. 



Diagnostic description: Piceous black color, the prothorax (ex- 

 cept three black pronotal spots, one medio-apical and a smaller one 

 on each side), head, mesosternum, mesepisterna, and appendages red- 

 dish yellow; mesepimera and hind coxae piceous; lateral piceous spots 

 of pronotum only slightly smaller than median apical spot, placed far 

 laterally, slightly anteriad of middle, and about equidistant from 

 apex and side of pronotum, median apical spot always present, lateral 

 spots often weak, rarely not detectable; antenna beyond segments 1 

 and 2 darker than head; body moderately nitidous. Antennae rela- 

 tively long, length equal to about nine-tenths of width of pronotal base, 

 club 3-segmented. Postmandibular lobes short, lateral edges some- 

 what rounded and subparallel; terminal segments of maxillary palpi 

 moderately widened, width slightly more than twice length (Boyle, 

 1956, fig. 78, p. 165). Pronotal punctures coarse, becoming larger and 

 denser laterally where they are mostly separated by about the distance 

 of their diameters or slightly less; cephalic punctures small and dense 

 medially and apically, sparser and approximately as large as pronotal 

 punctures laterobasally near eyes; elytral intervals bearing minute 

 punctules more numerous than strial punctures and a weak meshwork 

 of fine fissures; elytra moderately nitidous, distinctly margined 

 basally. 



Variation: Boyle (1956) states the variation of the 230 specimens 

 he examined to be 3.31 to 5.11 mm in length and 1 52 to 2.35 mm in 

 width. The measurements of the one specimen examined in this study 

 are: length 3.77 mm; width 2.03 mm. 



Male genitalia: The anterior end of the internal sac is illustrated 

 by Boyle (1956, p. 166, fig. 94). 



Type: Boyle (1956) chose a lectotype from a series of 5 cotypes 

 at the USNM and labelled it "Lectotype, Boyle, 1952." The material 

 examined in this study included one specimen from Chiapas, Mexico. 



Triplax rediviva Gorham 



Figures 5, 6 

 Triplax redivia Gorham, 1888, p. 79, pi. 4 (fig. 19). 



Diagnostic description: Elytra ferrugineous to piceous; scutellum 

 testaceous to ferrugineous; head and pronotum testaceous; metathorax 

 and abdomen ferrugineous; rest of underside, including legs, testace- 

 ous; antennae wholly testaceous; metacoxae usually ferrugineous. 

 Body moderately nitidous. Body shape elongate- elliptical, anterior 



