Molorchus bimaculatus Classification Family Cerambycidae > Subfamily Cerambycinae > Tribe Molorchini > Genus Molorchus Diagnostic Features of Larvae Larva. Form depressed, elongate, tapering posteriorly; integument thin, shining, sparsely covered with fine whitish hairs. Head as in Obrium rufulum, but thicker in front; one indistinct ocellus; genal setae more numerous and longer; first and second antennal joints transverse, subequal, third longer; last joint of maxillary palpi as long as two transverse basal ones; process of palpifer distinct. Pronotum about twice as wide as long, posteriorly reticulate, shining, then dull granulate; sternum coarsely granulate, shining. Mesonotum and metanotum granulate, shining. Legless. Ampullae coarsely granulate, shining. Pleural discs indistinct. Spiracles very minute, inconspicuous, orbicular, peritreme thin. Pupa. Three transverse groups of long setae on pronotum; mesonotum and metanotum glabrous; several finer setae on second abdominal tergum, third, fourth, fifth and sixth abdominal terga bearing two groups of from three to six small chitinous setiferous points; two recurved points and several setae on seventh; eighth bearing many long setae. Adapted from Craighead (1923). Biology and Economic Importance This species attacks a variety of recently dead trees, mining the smaller branches. The larvae practically mature beneath the bark, making irregular mines 8 to 10 inches long. On entering the wood a long curved pupal cell is made, often 3 inches in length. At the posterior end the larva pupates behind a wad of fibrous frass. One generation occurs each year, but the larvae mature very rapidly. From eggs laid in April pupae and adults can be found in late August. The adults hibernate in the cells. Adapted from Craighead (1923). Selected References to Larvae Specimens Craighead, 1923