306 NEOTROPICAL PSELAPHIDAE 



features are approached by Hamotus: the abdominal margin, the relative 

 lengths of the first two tergites, and the extent of the palpal sulcus vary among 

 the species and, as will be seen, this variation is taken advantage of in the keys 

 to species. The development of the palpal sulcus seems to be the best criterion: 

 in Apharus this sulcus never extends for more than the apical half of the internal 

 face, while in those Hamotus with a shortened sulcus, this latter extends into 

 the basal third of the internal face. 



The maxillary palpi of Apharus are four-segmented; first segment very 

 small as usual among Tyrini; second elongate, basally slender and arcuate, grad- 

 ually expanding to an oblique apex; third short, triangular; fourth much the 

 longest and widest, elongate-ovoidal, obliquely truncate at base, rounded at 

 apex, the internal face with an elongate-oval fovea or sulcus occupying the an- 

 terior half of the segment, with the palpal cone set within the apex of this palpal 

 sulcus at an oblique angle (PL XX). 



The males, where known, have the anterior trochanters each armed with a 

 tooth. Both sexes have the metastemum variously sulcate, impressed and tu- 

 berculate. The posterior tibiae are without spurs in the male of mulleri and 

 armipes, have the spurs well developed in the female of armipes and lacking in 

 the female of colombiensis. 



The following key to species does not account for clavicornis Raffray with 

 which I am unfamiliar, and the reference to which I have been unable to check. 



Anterior trochanters armed with a tooth .... Males 2 



Anterior trochanters unarmed. . . .Females 3 



2. Metasternum simply impressed at apex; occiput gradually formed; 



pronotum with length and width subequal ; length 2.0 mm. . . mulleri 

 Metasternum medianly sulcate, with a large tuberculate tooth each 



side; occiput abruptly and sharply formed; length 1.85 mm 



armipes 



3. Posterior tibiae without spurs ; occiput abruptly and sharply formed ; 



pronotum transversely subglobose, being one-third wider than long; 

 disc of elytron with a dorsal depression for basal third ; metastemum 



medianly sulcate and tuberculate each side; length 1.20 mm 



colombiensis new species 



Posterior tibiae each with a strong arcuate spur; pronotum subglobose; 

 disc of elytron lacking a dorsal depression; occiput and metasternum 

 as above ; length 1.85 mm armipes 



Apharus colombiensis new species 



Type Female. 1.20 mm. long x 0.60 mm. wide through elytra. Shining 

 reddish-brown, convex, 40 per cent smaller than the allied armipes, and with 

 long, coarse, semierect, flavous pubescence. Head, pronotum and abdomen 

 lightly punctulate; elytra with a few very large coarse punctures; femora and 

 antennal club scabroid. 



