Colliuris DeGeer, 1774

Bousquet, Yves, 2010, Review of the Nearctic, Mexican and West Indian (Greater Antilles) species of Colliuris Degeer (Coleoptera: Carabidae: Odacanthini), Zootaxa 2529, pp. 1-39 : 3-4

Genus Colliuris DeGeer, 1774

Colliuris DeGeer, 1774: 79 . Type species: Attelabus surinamensis Linné, 1767 , by monotypy. Collyris Agassiz, 1846: 94 . Unjustified emendation for Colliuris DeGeer, 1774 .

Diagnosis. The proportionally narrow and elongate pronotum in combination with the vertex being clearly narrowed posteriorly make adults of this genus very characteristic within the carabid fauna of the area covered in this work.

Description. Dorsal integument glabrous (except for fixed macrosetae) in most species. HEAD. Vertex markedly narrowed posteriorly. Frons with two supraorbital setae on each side, though one or more similar setae present also laterally on frons in a few species. Eye protruding, markedly so in some species. Anterior edge of labrum transversely truncate or with a short median, rounded projection. Antenna pubescent from antennomere 4; antennomeres filiform. Apical labial and maxillary palpomeres fusiform; penultimate labial palpomere bisetose. Mentum with median tooth, tooth acuminate apically, its anterior edge not emarginate; paramedian pits absent. PROTHORAX. Pronotum more or less cylindrical, distinctly longer than wide; lateral side poorly defined, with one or more setae in almost all species seen; anterior and posterior angles poorly defined; posterior angle without seta. Proepipleura visible from above. Prosternal apophysis not marginated. METATHORACIC STERNITES. Metepisternum elongate. ELYTRA. Subbasal ridge absent. Humerus widely rounded. Apical edge obliquely subtruncate to emarginate. Epipleuron without subapical plica. LEGS. Tarsomere 4 with apical edge slightly emarginate, not deeply cleft; tarsomere 5 with setae underneath. Tarsal claws smooth, not pectinate.

Geographical distribution. The genus Colliuris as presently conceived is represented over most of the warm temperate, subtropical and tropical regions of the New World only, including the West Indies. All Old World taxa included by Liebke (1938) in the genus Colliuris are now grouped under different genera (see Lorenz 1998).

Bionomics. Very little is known about the biology of these species. Even the habitat requirements are virtually unknown for several species. However, the biology of one species ( Colliuris batesi Chaudoir ) was study in central Amazonian inundation forests by Adis et al. (1997). The diurnally-active adults live on the surface of the forest floor and are excellent climbers. During the aquatic phase, they are capable of moving on the water surface and can be collected on branches and trunks above the waterline. They feed on a variety of small, preferably soft-bodied invertebrates, mostly arthropods. Larvae are nocturnal and live in tunnels constructed near the soil surface at moist sites. Their development last for 26 more or less 4 days in the laboratory at 24o C or 27/21o C. The species is bivoltine. Females glued their eggs singly onto stones or pieces of wood close to the soil surface, each enveloped in a cover of fine-grained soil particles. The species is wingdimorphic with a much greater percentage of brachypterous specimens.

Note. The name Casnonia , credited to Latreille [in Latreille and Dejean] (1822), an incorrect subsequent spelling of Cosnania Dejean, 1821 , was used for a long time as the name of this genus. Latreille (1822) used the name Casnonia because he did not recognize the Colliuris of DeGeer. DeGeer’s name remained unused until the work of Liebke (1930, 1938).

Liebke (1930, 1938) recognized an array of subgenera of Colliuris . I have preferred to use informal species groups instead of subgenera because this work covers a relative small portion of the species and several of Liebke’s subgenera are probably polyphyletic. A modern revision of all species is necessary to set the limits of the subgenera.