圖6-29BoysidiagracilisHaas,1937Arch.Moll.,69:7,f.18-20BoysidiagracilisYen,1939Abh.Senckenb.Naturf.Ges.,444:76,pl.6,f.43.模式標(biāo)本產(chǎn)地湖北巴東。形態(tài)特征貝殼微小,殼質(zhì)薄,呈細(xì)長(zhǎng)圓錐形。有61/2個(gè)螺層,前幾個(gè)螺層增長(zhǎng)稍快,各螺層略膨脹,螺旋部呈圓錐形,體螺層 (共 691 字) [閱讀本文] >>