Taxonomic review of New World Tachyina (Coleoptera, Carabidae): descriptions of new genera, subgenera, and species, with an updated key to the subtribe in the Americas Author Boyd, Olivia F. Author Erwin, Terry L. text ZooKeys 2016 626 87 123 http://dx.doi.org/10.3897/zookeys.626.10033 journal article http://dx.doi.org/10.3897/zookeys.626.10033 1313-2970-626-87 3DE781B6D48B432B97846703EA6B280B Taxon classification Animalia Coleoptera Carabidae Genus Polyderidius Jeannel, 1962 Figs 2B, 3B, 4B, 5B Type species. Polyderidius rapoporti Jeannel, 1962 by original designation. Diagnosis. Mentum with paired, circular foveae; head with three pairs of supraorbital setae (Fig. 3B), antennae submoniliform; elytral apices rounded/truncate (Fig. 2B), apical recurrent groove hooked anteriorly (Fig. 4B). Many species have reduced eyes and some are brachypterous. Description. Size. ABL = 1.0-1.2 mm; SBL = 1.1-1.3 mm; TW = 0.45-0.5 mm. Form. Minute, delicate, dorsolaterally compressed. Color. (Fig. 2B) Uniformly flavous, flavous with darker head, or uniformly testaceous. Microsculpture. Varied, from coarse/scaly/isodiametric to fine/linear/transverse. Head. Head with three pairs of supraorbital setae (Fig. 3B); mentum with paired circular or oval-shaped foveae, or with pair of shallow impressions; eyes reduced in most members; antennae submoniliform and densely setose; subapical labial palpomere conspicuously large and bulbous. Prothorax. (Fig. 3B) Basal section of pronotum triangular; posterior angles of pronotum bluntly square to rounded and slightly obtuse; procoxae narrowly separated by apically pointed prosternal process; male without dilated basal protarsomere(s). Pterothorax. Elytral interneurs (if visible) punctate to striatiopunctate and very faintly impressed; i1 often entire, striatiopunctate; no trace of i8; apical recurrent groove (Fig. 4B) thin, well-impressed, and hooked anteriorly; elytral apex (Fig. 2B) rounded and truncate; flight wing with fringed margin, or reduced to a minute pad. Abdomen. Terminal ventrite with two (male) or four (female) elongated setae. Genitalia. See Jeannel 1962 . Distribution. Known from across South and Central America, Mexico , the southeast United States (Alabama, Mississippi), Hawaii, and islands of the Caribbean (Puerto Rico, Cuba) with the greatest species diversity in the Amazon basin ( Adis et al. 1986 ).