ELMIDAE Author: John F. Lawrence, 2001. Classification Suborder Polyphaga, Series Elateriformia, Superfamily Byrrhoidea. Description Antenae with 7-11 segments, filiform or clavate, or with a 5 or 6 segments club. Antennal insertions exposed. Visible portion of procoxa transversae to globular with the trochantin concealed to at least partly exposed. Procoxal cavity externally open and internally open. Mesocoxae separated by 0.4 to more than 1 coxal width, with mesocoxal cavity laterally open. Tarsal formula 5-5-5. Numberof ventrites 5 with 3 connate. Body length 1-7 mm. Ovate to elongate. Legs long, with large claws. Undersurface often with silvery sheen (plastron). Quick identification Typical Elmidae (right) can usually be recognized by their glabrous upper surface, long legs with simple tarsi, glabrous, filiform antennae. Most members of Larainae (first and second figure) have a pubescent upper surface, shorter, pubescent antennae, and shorter tarsi. Most elmids also have a silvery sheen beneath the body caused by specialized hairs used in capturing a water bubble. Genera occurring in Costa Rica Larainae: Disersus, Hexanchorus, Phanocerus, Pharceonus, Pseudodisersus. Elminae: Austrolimnius, Cylloepus, Heterelmis, Hexacyllopeus, Macrelmis, Microcylloepus, Neocylloepus, Neoelmis, Notelmis, Onychelmis, Portelmis, Stenhelmoides, Xenelmis. © CSIRO Emtomology, 1999 Larainae: Disersus © CSIRO Emtomology, 1999 Larainae: Phanocerus © CSIRO Emtomology, 1999 Elminae: Stenelmis (exotic) Derechos Reservados INBio. Copyrights INBio