PROC. ENTOMOL. SOC. WASH. 108(4), 2006, pp. 878-884 MESOPHYLETIS C4L//0(/A7(MESOPHYLETINAE), A NEW GENUS, SPECIES, AND SUBFAMILY OF EARLY CRETACEOUS WEEVILS (COLEOPTERA: CURCULIONOIDEA: ECCOPTARTHRIDAE) IN BURMESE AMBER George Poinar, Jr. Department of Zoology, Oregon State University, Corvallis, OR 97331, U.S.A. (e-mail: [email protected]) Abstract. — A new subfamily, genus and species of weevils (Coleoptera: Curculio-noidea; Eccoptarthridae: Mesophyletinae: Mesophyletis calhouni Poinar) are de-scribed from Cretaceous Burmese amber. This fossil differs from all previously described Cretaceous weevils in having definite geniculate antennae with an elongate scape and antennal scrobes, prolonged trochanters, toothed tarsal claws, and long pedunculate lobes on the third tarsal segment. The presence of the latter characters suggests that its life style was arboreal. Key Words: Eccoptarthridae, Mesophyletinae, new subfamily, Mesophyletis.. new genus, Mesophyletis calhouni, new species, Burmese amber. Early Cretaceous, Curculionoidea Mesozoic weevils are uncommon and almost all belong to the primitive weevil Division Orthoceri, which include species with straight antennae (Alonso-Zarazaga and Lyal 1999; Gratshev and Zherikhin 2003; Ponomarenko 1995; Zimmerman 1993, 1994a). Thus it was of interest when a weevil in Early Cretaceous Burmese amber was discovered with definite geniculate antennae. The present study describes this weevil and discusses its possible biological affiliations based on functional morphology. Materials and Methods The amber piece containing the fossil is roughly square in outline, measuring 8 mm long by 7 mm wide and 3 mm in depth. Observations, drawings, and photographs were made with a Nikon SMZ-10 R stereoscopic microscope and Nikon Optiphot compound microscope with magnifications up to 600 X. Amber from Burma occurs in lignitic seams in sandstone-limestone deposits in the Hukawng Valley. Nuclear mag-netic resonance (NMR) spectra of amber samples taken from the same locality as the fossil indicates an araucarian (possi-bly Agathis) source of the amber (Lam-bert and Wu, unpublished research 2002). Palynomorphs obtained from the amber beds where the fossil piece originated have been assigned to the Upper Albian of the Early Cretaceous (100-110 mya) (Cruickshank and Ko 2003). The Burmese amber weevil is well preserved and complete, with all its appendages still attached (Fig. 1). Since it could not be placed in any extant or extinct genus, it is described below in a new subfamily of the family Eccoptar-thridae. Systematic treatment of families and subfamilies is based, in part, on that of Alonso-Zarazaga and Lyal (1999).