Fine structural observations on coccolithophorids from south alaska in the genera papposphaera tangen and pappomonas manton and oates

Abstract

Representatives of two unusual genera of coccolithophorids have been recognized in the New World for the first time, in whole mounts set up at Homer, South Alaska, in June 1975 and subsequently examined electron microscopically. A new species of Papposphaera Tangen is described in a preliminary way (P. sagittifera sp. nov.) and structural observations on both known species of Pappomonas Manton & Oates have amplified existing information, more especially on the base-plates of the coccolith appendages. In both species of Pappomonas, the resemblance between Alaskan specimens and those from West Greenland is close, but differences between one of these and the equivalent from the southern hemisphere are much greater. It is therefore concluded that this species may find it easier to migrate directly from ocean to ocean via an arctic route, than to cross the equator from the north to the south Atlantic. The morphological findings are recognized taxonomically by the erection of a new variety (P. ftabellifera var borealis) which is defined. © 1976 Taylor & Francis Group, LLC.