90 NEOTROPICAL PSELAPHIDAE 



Panama, Guatemala, Mexico, and up the Mississippi and Ohio river valleys. 



This genus is very well-marked. The eyes are well-formed, large and with 

 coarse facets as a rule. The eleven-segmented antennae have a large two to 

 three-segmented club, of which the distal segment is characteristic. This 

 eleventh segment is formed in two portions, as in Eutyphlus, but not so sharply 

 differentiated as the latter. The basal piece is large, more or less cylindrical, 

 but the apical piece is pyramidal or conical and much smaller, being set within 

 the circular distal face of the basal piece. The ninth and tenth obviously and 

 increasingly transverse, the eleventh much longer than wide, longer than ninth 

 and tenth combined, not much wider than tenth segment. Vertexal foveae large 

 and pubescent. Pronotum with lateral margins crenulated ; disc with a median, 

 longitudinal ovate puncture of varying proportions and size among the species; 

 base with a large pubescent lateral fovea each side, connected more or less 

 indefinitely with a median, nude impression by a transverse sulcus; basal margin 

 with a brief, longitudinal carina which does not reach the median impression. 

 The elytra have three basal pubescent foveae each, a sutural, median, and 

 lateral. The sutural and median foveae of each elytron are characteristically 

 enclosed by the strong sutural stria which passes anteriorly, parallel with the 

 mesial elytral margin, to a point anteriad of the sutural fovea, where it curves 

 laterally to pass above and over the anterior margins of the sutural and median 

 fovea, enclosing them, and then curving posteriorly, sharply, just lateral of the 

 median fovea, and ending before the middle of the elytra. The lateral basal 

 fovea is by itself and also more or less enclosed in a discal stria which ends 

 posteriorly before the middle of the elytron. In addition, the humeri are well 

 marked, set off by an oblique humeral line, and below this, on the subhumeral 

 flank, is a large pubescent subhumeral fovea and long stria which extend pos- 

 teriorly nearly to the apex of the flank. The prosternum is longitudinally and 

 medianly carinate. The abdomen has no apparent basal carinae, and is sexually 

 differentiated: males with seven sternites, the seventh being a circular, simple, 

 one-piece, asymmetrically articulated pygidium ; females with six sternites. The 

 metathoracic coxae are broadly subconical, and consequently the first sternite 

 is seen between them medianly as a triangular field, and laterally well shown 

 where the coxae narrow markedly near the elytral flanks. 



Key to the Species 

 Vertex with three foveae across middle, between the eyes; size rela- 

 tively large, nearly two millimeters long impressifrons 



(1.85 mm.; 4000-5000 ft., Cerro Zunil, Guatemala) 

 Vertex with two foveae on the middle of the vertex, between the eyes ; 

 size smaller, not longer than one and one-third millimeters 2 



2. Head relatively large, as wide through the eyes as the pronotum .... 3 

 Head relatively small, including the eyes, distinctly narrower than the 



pronotum; pronotum very transverse, about one-third wider than 

 long 5 



3. Eighth antennal segment strongly transverse, almost as wide as ninth 



antennal segment 4 



