Original descriptions of taxa. For coccolithophores, and many calcispheres, these are pages from the Farinacci & Howe Catalog of Calcareous Nannofossils. In other cases (e.g. non-calcifying haptophytes) the data is directly compiled on this site. The "Catalogue of Calcareous Nannofossils" was originally compiled by Prof A. Farinacci 1969-1989, since 2000 it has been updated and extended by Richard Howe - see The Farinacci and Howe Catalog - an Introduction.
Taxa are sorted alphabetically for simple browsing, or you can use search boxes at the top & bottom of the page
Citation: Chrysochromulina rotalis Eikrem&Throndsen 1999Taxonomic rank: speciesType sample (& lithostrat): isolated from a serial dilution culture (Throndsen 1978) inoculated with sur face water collected in the Skagerrak (58° 11'N, 09°06'E; off Hirtshals, Denmark) on 30 June 1990.Farinacci catalog page (& compiler): n/a Current citation: Chrysochromulina rotalis Eikrem and Throndsen 1999
Original Description Cells saddle shaped measuring 4-6 µm with two chloroplasts. Two flagella, usually equal 8-18 pm. Haptonema 22-80 µm long, coiling. Periplast covered with dimorphic scales, in two layers; outer layer scales slightly elongate, 450-570 x 350-470 nm, with spine supported by four decurrent struts, spine approximately equalling the scale radius; inner layer scales slightly elongate, 400-550 x 320-460 nm, without protrusions. Proximal scale faces with concentric fibrils and distal faces with radiating ribs. Extra details from original publication The cells of C. rotalis are typically saddle shaped with two golden brown parietal chloroplasts. Each chloroplast has a pyrenoid (not illustrated) which can barely be seen in the light microscope. The outline of the cell is apple shaped in ventral or dorsal views (Figs 1, 3 & 4), the length and width being almost equal, measuring 4-6 µm. In lateral view (Fig. 2) the outline is bean shaped, the dorsiventral axis being approximately half of the cell length. As can be seen in Fig. 2, the cell axis is kept at an angle of approximately 30° to the plane of the haptonema and flagella. The two flagella are usu ally equal to subequal in length, measuring 8-18 pm. The haptonema is long, normally 22-80 µm when ex tended (Figs 1-3), and easily visible also when coiled (Fig. 4 arrowhead). During normal swimming the flagella beat homodynamically along the sides of the cell, pushing the cell with the haptonema pointing for ward (Figs 2 & 3), or they are reversed while the hapto nema is dragged behind the cell (Fig. 1). This is also the case when the haptonema attaches temporarily to the cover slip surface.
The periplast is covered with two types of scales; plate scales and spine scales (Figs 5-8). The distal faces of both types have concentric fibrils which may be revealed in negative stained (Fig. 7) or shadow cast preparations (Fig. 6). The proximal faces have radiating ribs most easily seen in shadow cast preparations (Figs 5 & 6), but also evident in sections; in Fig. 9 showing a glancing section of an embedded scale both the concentric pattem of the proximal side and the radial pattem of the distal side can be seen. The scales ofthe outer layer bear short spines approximately equal to or shorter than the radius of the scales (Figs 6 & 8). The spines are supported by four decurrent struts.
References:
Eikrem, W. & Throndsen, J. (1999). The morphology of Chrysochromulina rotalis sp. nov. (Prymnesiophyceae, Haptophyta), isolated from the Skagerrak. Sarsia. 84: 445-449. gs
Chrysochromulina rotalis: Catalog entry compiled by Jeremy Young. Viewed: 17-2-2025