118 - HETEROMERA. 
A single species, of small size, from Costa Rica. This genus may be separated from 
Haplandrus and Isicerdes, apart from other differences, by the oblique intermediate 
coxee and the scarcely visible trochantin ; in this latter respect more nearly approaching 
the group “ Ulomides.” The comparatively short thorax (the hind angles of which are 
acute and divergent), long elytra, the antenne very distinctly widening outwardly (the 
apical joint very large), and the almost obovate form will enable Idus to be readily 
recognized amongst its allies. 
1. Ilus apicicornis. (Tab. VI. fig. 3.) 
Obovate, moderately convex, rather depressed above, black, shining. Head finely and distinctly punctured, 
the epistoma separated from the front by an impressed transverse line, and with a shallow rounded 
impression on each side before the eyes; prothorax short, strongly transverse, as wide in front as behind, 
the sides rounded, narrowed and sinuate before the base, hind angles acute, outwardly directed, and 
prominent, anterior angles broadly rounded and slightly produced, feebly emarginate in front, base strongly 
bisinuate, shallowly, finely, and not very closely punctured ; elytra very long, a little wider than the 
thorax, widening gradually from the base to the widest part some distance beyond the middle, beyond 
which broadly rounded to the slightly produced apex, the base shallowly depressed about the scutellum 
and on each side within the slightly prominent obtuse humeri, with regular rows of shallow coarsish 
impressions placed upon shallow obsolete strie, the impressions becoming coarser outwardly and finer and 
closer towards the suture. 
Length 9 millim. 
Hab. Costa Rica, Cache (Rogers). One example. 
CHOASPES. 
Choaspes, F. Bates, in litt. 
Mentum narrow, about as broad as long, strongly inflexed on each side, longitudinally convex and much raised 
in the middle, anterior angles rounded; antenne short, stout, widening outwardly, third joint short, 
fourth about the length of the third, eighth to tenth broader than long, eleventh large and broad, and 
almost as long as the united ninth and tenth; inner lobe of the maxille with a few spiny hairs at the 
apex; apical joint of maxillary palpi securiform; head short, broad, the epistoma broadly rounded in 
front in the female, subtruncate in the male; sides of the front (antennary orbits) slightly divergent, 
rounded, and prominent ; eyes distant, transverse, moderately large and prominent, coarsely granulated ; 
labrum not prominent; prothorax transverse, flattened above, base strongly bisinuate, deeply emarginate 
in front, lateral margins reflexed and prominent, angles produced and prominent, closely embracing the 
elytra; scutellum large, triangular; elytra broader than the thorax, convex, comparatively short and 
broad, about two and a half times as long as the thorax, and with a short scutellar and eight regular rows 
of coarse longish impressions placed upon feebly impressed strie, transversely impressed on each side before 
the base ; humeri obtuse; epipleurz broad, smooth, feebly concave, narrowed gradually from the base 
and ending abruptly just beyond the last ventral suture, and separated from the elytra by a very distinct 
keel; prosternum horizontal, the apex produced and sublanciform, longitudinally impressed on each side, 
the sides distinctly raised, the middle more or less longitudinally convex ; mesosternum raised into a distinct 
tubercle on each side in front, deeply excavated within ; legs short ; the tibize distinctly channelled on their 
outer edge, slightly curved, short, the spurs obsolete or indistinct ; anterior and intermediate femora slightly 
swollen in the middle, sinuate or emarginate before the apex; posterior femora in both sexes swollen and 
with a large triangular blunt tooth on the inner side near the middle, between which and the apex 
emarginate ; tarsi rather stout, short, basal joint of the hinder pair as long as the two following joints 
united. Winged. Species submetallic in colour ; form comparatively broad, convex. 
