Staphi/linidcB of the Amazon Valley. 225 



Labrum breve, medio sinimtiim. Mandibulre robustse, 

 medio trideutata?. Maxillas mala interiore lata, barbata, 

 exteriore siibelongata, apice dense longeque barbata. Palpi 

 maxillai-es articulo primo secundo duplo breviore, hoc sat 

 elongato, basi angustiore ; tertio secundo longiore, valde 

 incrassato, basi constricto. Labium* paraglossia valde 

 elongatis, acuminatis. Palpi labiales articulo primo 

 secundo fere duplo breviore, hoc elongato, cylindrico ; 

 tertio brevi, angustissimo, secundo fere quadruple breviore 

 et angustiore. Antennae crassiusculjB, elongate, vix 

 fract^. Thorax angustus, elongatus, basi apiceque at- 

 tenuatus ; presternum magnum, convexum. Elytra trun- 

 cata. Abdomen apicem versus leviter incrassatum ; penis 

 magnus, latus, oblongo-ovalis. Pedes sat elongati ; tibiis 

 anticis basi dilatatis, medio subito constricto ; tarsis om- 

 nibus simplicibus, articulo primo secundo duplo lon- 

 giore. 



Habitus singularis, capitis forma Ophitidem referens, a 

 quo oris partibus, antennis subfractis, tibiarumque auti- 

 carum structura singulari, discedit. 



1. Sphceronum opacum, n. sp. Elongatum, opacum, 

 capite, thorace, antennisque nigris, pedibus testaceis, elytris 

 abdomineque obscure rufescentibus ; dense subtilissimeque 

 punctulatum, subtilissimeque griseo-pubescens. Long. 

 Corp. 5 1 lin. 



Mas : abdomine segmento 6" ventrali apice medio de- 

 presso, semicirculariterque exciso; segmento 7° late im- 

 presso, apice emarginato excisoque. 



Antenna3 nearly as long as head and thorax, black, not 

 in the least thickened towards the extremity; 1st joint 

 more than twice as long as 2nd, 4 — 10 differing but 

 little from one another ; last joint rather longer than the 

 10th. Head black, about as broad as the elytra, closely 

 and finely pvmctured and pubescent, produced behind into 

 a stout, ti'icarinate neck, the hind margin of which is 

 truncate. Thorax considerably narrower than the elytra, 

 twice as long as broad, much narrowed to the base and to 

 the front, its greatest width at about two-thirds of the 



• The ligula is distorted in the preparation I have made of the trophi, 

 but as far as I can see it appears to be entirely corneous ; if this be the case, 

 it will add another remarkable character to this very distinct genus. 



TRANS. ENT. SOC. 1876. — PART II. (jUNE.) Q 



