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Oxycorynini are a tribe of American belids, primitive weevils of the family Belidae. Like in other belids, their antennae are straight, not elbowed as in the true weevils (Curculionidae). In contrast to other Belidae, Oxycorynini larvae feed on flowers or several types of fruit.〔 The Oxycorynini contain 7 genera, the bulk of the subfamily Oxycoryninae. But while they are highly diverse, they are not particularly speciose, with nearly 20 described and a few undescribed species compared to the more than 150 Hawaiian species of ''Proterhinus'' of the Aglycyderini.〔 The fossil record shows that the three Oxycoryninae tribes were well distinct by the mid-Paleogene, about 50 million years ago (mya). The belids as a whole are of Jurassic origin, and the Oxycorynini must thus have evolved in the Late Cretaceous or perhaps Paleocene, roughly some 100-60 mya.〔Marvaldi ''et al.'' (2006), Ming ''et al.'' (2006)〕 ==Description== The adult Oxycorynini have a number of fairly characteristic traits, but they are not present in all members of this tribe. Many have a pronotum whose hind margin is at least as wide as the elytra bases, often wider. Except in the rather primitive ''Oxycraspedus'', the first tarsomere is smaller than the second, and microscopically the lack of spermatheca, with the spermathecal duct directly inserting on the common oviduct, is conspicuous.〔 Adults of ''Parallocorynus'' and ''Rhopalotria'' are peculiarly soft-bodied and possess several characteristic traits: their gular sutures are fused to a single suture, their elytra cannot be locked in open position and have round tips between which the pygidium can be seen. The sternite of their mesothorax slants forward, but the part protruding between the second leg pair is not raised. Finally, their spermathecal gland and spermathecal duct form a common tube. ''Alloxycorynus'' and ''Hydnorobius'' adults have two gular sutures which form a semicircle at the head base and end in distinct tips; their elytra are ribbed lengthwise. Adults of ''Balanophorobius'' and ''Oxycorynus'' have a flattened hindside of the metathoracal sternite.〔 More characteristic are the larvae. Their labrum has two sensilla at the base and two more towards the center of the forward maring. They have a typical body shape with recurved hindparts; the anus opens on the underside. Except in ''Oxycraspedus'', the dark forehead is bordered by a ridge towards the back, where the cuticle attaches, and the body is widest in the middle of the abdomen. And of course, Oxycorynini larvae differ from other belids in that their larvae do not feed on dead or decaying wood but on flowers and fruits.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Oxycorynini」の詳細全文を読む スポンサード リンク
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