THINOBIUS. 705 
Group THINOBIINA. 
It is necessary to separate Thinobius and its immediate allies from the other groups 
of the subfamily “Oxyteline,” as they possess a different structure of the prothoracic 
side-pieces and of the front coxe, making some approach in these respects to the 
subfamily ‘“ Aleocharine.” 
THINOBIUS. 
Thinobius, Kiesenwetter, Stett. ent. Zeit. 1844, p. 855; Leconte, Tr. Am. Ent. Soc. vi. p. 239 
(1877). 
This genus comprises at present about twenty species, all from the European and 
North-American region, with the exception of one from Chili. They are amongst the 
most minute of Coleoptera, and it is quite probable that the genus will prove to be rich 
in species and widely distributed. The different species are found in muddy places, 
and especially about the sandy banks of rivers and streams. 
1, Thinobius tenuis. (Tab. XVIII. fig. 22.) 
Fusco-piceus, antennis pedibusque sordide testaceis; antennis longissimis, fere ad elytrorum apicem attingentibus; 
omnino subtilissime punctulatus, opacus. 
Long. 13 millim. 
Hab. Guatemata, San Gerénimo (Champion). 
Antenne slender and elongate; third joint more slender and much shorter than the 
second ; terminal three joints very elongate, scarcely perceptibly thicker than those 
preceding them. Thorax obscure red, nearly straight at the sides, rather strongly 
transverse. Elytra one and a half times as long as the thorax. Hind body distinctly 
pubescent. 
This insect is about the size of the European T. longipennis, but has a more elongate 
head and thorax and remarkably long antenne. Five examples. In our figure the 
antenne are represented as very much thicker than they should be. 
2. Thinobius thripsoides. 
Fascus, antennarum basi pedibusque sordide testaceis; antennis tenuibus, modice elongatis; omnino subti- 
lissime punctulatus. 
Long. 13 millim. 
Hab. Guatemata, San Gerénimo (Champion). 
Antenne with the terminal joints slender, though slightly broader than the others; 
none of the joints transverse, the terminal joint short. Head very narrow, the eyes 
very small. Thorax about twice as long as broad. Elytra about twice as long as the 
thorax, very dehiscent at the apex. ‘Two examples. 
This species is extremely similar to the European 7. longipennis, but is not half the 
size, and has a narrower head and smaller eyes. 
BIOL. CENTR.-AMER., Coleopt., Vol. I. Pt. 2, February 1887. 4AXX 
