324 NEOTROPICAL PSELAPHIDAE 



are lightly punctulate and antennal club which is subgranulate. Pubescence 

 yellowish-brown, long, silky, and abundant. 



Head as in castanalus save for the following: vertex not unusually vaulted 

 but is medianly depressed; the small antennal tubercles are distinctly separated 

 by a longitudinal sulcus instead of a median depression ; eyes of about 88 facets. 

 Front, clypeus, labrum, ventral surface of head, and maxillary palpi as in 

 costaricensis. 



Antennae 0.87 mm. long; I to X as in castanalus; XI distinctive, being 

 three-fourths as wide as long, and as long as the preceding five segments united. 



Pronotum slightly transverse with the sides nearly parallel ; three antebasal 

 pubescent foveae, of which the median is slightly smaller and more circular. 



Each elytron with two large, circular, pubescent basal foveae; an un- 

 usually broad, deep, sulcoid sutural stria; a relatively long dorsal sulcoid 

 impression extending from outer fovea through basal third of elytral length. 



Wings long and well-developed. 



Abdomen with five visible tergites in a length ratio of 5/3.5/2/1.5/2 

 having the first three margined as usual. The last tergite is sexually dis- 

 tinctive, being broadly subtriangular. 



Six sternites in a length ratio of 1/3/2.5/1/.8/.8 with the last four slightly 

 flattened. The penis is exserted between the last sternite and tergite, establish- 

 ing the sex of the type. 



Metastemum as in alleei. Intermediate coxae separated by less than one- 

 third, and posterior coxae separated by slightly more than one-half, the median 

 metasternal length. Legs as for genus; posterior tibiae each with an apical 

 spur. This spur is sharply angulate at base, thick, subtruncate, and composed 

 of six very stout setae. 



Described on nine specimens, all from Vera Cruz, Mexico, as follows: 

 type male and four paratypes from Tezonapa, one paratype from Penuela; 

 two paratypes from Tuxpango collected by Henry Dybas in July and August, 

 1941, and one male paratype from Cordoba on July 20, 1936, collected by 

 C. H. Seevers. 



The female sex has the eleventh antennal segment as long as the preced- 

 ing four united; the sternites normally convex; the last tergite broadly 

 trapezoidal with the apical margin concave. The form of the terminal tergite 

 rapidly sexes the species, while the sexual variation in the distal antennomere 

 is a good illustration of a quantitative differential, in contrast to the qualitative 

 differences in the club of veracruzensis. There is some variation in the third 

 antennal segment, some specimens having this segment as long as wide and 

 others wider than long, but never longer than wide, which, therefore, quickly 

 separates aztekus from ursulus, simplex and other species with a distinctive 

 elongate third antennomere. From its nearest allies aztekus differs in the long 

 distal antennal segment of the male. The relatively short second sternite and 

 elytra are also diagnostic. 



In the following descriptions of three new species of the subgenus 

 Hamotoides I have given a tolerably full account of one species and contrasted 



