TETRAGONOMUS.—MEGALOSTYLUS. 24 
pond 
Hab. Panama, Bugaba (Champion). 
Four specimens, one (apparently female, with a very short claw to the middle 
tibie) free from incrustation, and showing the sculpture and vestiture much better 
than the others, which are certainly males. 
MEGALOSTYLUS. 
Megalostylus, Schénherr, Gen. Cure. vi. 1, p. 114 (1840); Lacordaire, Gen. Col. vi. p. 111. 
Megalostylus agrees with Cyphus in having the posterior tibiz laminate and squamose 
at the apex, and their articular surface ascending, and the rostrum deeply, triangularly 
emarginate at the tip (so that there is no definite bare nasal plate) and sides; the 
outer strie of the elytra are entire; and the scape of the antennee of the male is very 
stout, as in Platyomus. It is related to the Antillean Apotomoderes, which has toothed, 
strongly clavate anterior femora and the corbels of the posterior tibize small and open, 
and to the new genus described below, in which the intermediate and posterior femora 
are so deeply excavate near the apex as to appear toothed. ‘The species, so far as at 
present known, are all confined to Mexico*, ‘They are extremely variable in size and 
in the colour of the scales (there being both green and cinereous forms f in at least 
three species); and the prothorax sometimes differs in shape in the two sexes, as in 
certain Steirarrhinus. The males may be known by their longer and stouter antennal 
scape, the broader third tarsal joint, the unguiculate apex of the intermediate tibie, 
and the more or less hollowed first ventral segment; the females are broader, and 
often have the prothorax less sinuate at the base and the hind angles more extended 
outwards than in the males. The anterior tibie are toothed at the outer apical angle 
in both sexes. The smallest specimens seen, as in Megalostylodes, are females. 
Unfortunately, nothing has been recorded of the habits of these insects, 
a. Eyes very prominent, rounded. 
a’, Prothorax with base deeply bisinuate and sides rounded; upper 
surface villose. 
a’. Scales green . 6. 1 1 ew ee we ew ew we ee Sturmt, Boh. 
b?. Scales cinereous . . . . ww we eee ew ee ee) Sturm, Boh., var. 
6’. Prothorax with base moderately or feebly bisinuate. [ villosus, Chevr. 
ce’, Prothorax more or less conical. 
a’. Legs rufescent. 
a‘. Upper surface villose: scales metallic golden-green. . . . tomentosus, sp. n. 
b*. Upper surface not villose, elytra setose along the suture 
posteriorly : scales greenish or cinereous . . . . - « ~ rhodopus, Boh. 
* M. albicans has been recorded from California, probably in error, and M. renggerz, Labr. et Imhoff, from 
Paraguay, must belong to a different genus, 
+ Asin Hadromerus, Cyphus, Atactogenus, &c. 
BIOL. CENTR.-AMER., Coleopt., Vol. IV. Pt. 3, October 1911. 2 II 
