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.
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Citation: Prymnesium nemamethecum Pienaar&Birkhead 1994Taxonomic rank: speciesType specimens: Holotype: Figure 9. Culture Q 16 in the phycology culture collection of the University of the Witwatersrand.Type locality: Seawater (35ppt) from the sediment of the tidal pool at St. James, Cape Town, South Africa, collected in September 1988Farinacci catalog page (& compiler): n/a Current citation: Prymnesium nemamethecum Pienaar and Birkhead 1994
Original Description Cells elongate (8-18.5 µm x 6-11 µm), not compressed, being obliquely truncate anteriorly and posteriorly metabolic. Appendages subapically inserted in a depression and comprise two hererodynamic, subequal to unequal flagella (16-25 µm and 9.5-20 µm) and a short, noncoiling, but flexible. haptonema (2.5-6.3 µm). Cells covered by numerous. randomly scattered, muciferous bodies, and by three scale types. Up to six layers of proximal body scales occur. These proximal body scales are large, oval plate scales (0.84 µm x 0.6 µm), with proximal radiating ridge (about 30 per quadrant), and distally an inflexed rim and secondary coronate ornamentation on top of the radiating fibrils. The single distal scale layer consists of elliptical scales (0.65 µm x 0.34 µm) with proximal radiating ridge (about 20 per quadrant), which are also evident on the distal surface. The distal surface is further elaborated by a peripheral, upright wall and a long, central thickening that gives rise to alternating side branches. The third scale type is a simple plate scale (0.61 µ x 0.31 µm) with radiating ridges both proximally and distally (abut 20 per quadrant), but distally also having an inflexed, narrow rim and a small, central thickening. These cales may be distally concave along their long axis and occur only in the anterior region of appendage insertion, around the haptonema. Cells exhibit a smooth swimming behavior with the flagella directed posteriorly. Cells move forward revolving around the long axis with the anterior pole describing a wider helix. Two golden-orange, lobed chloroplasts, each with an obvious pyrenoid, lie parietally along the length of the cell. Other cell contents include the median nucleus between the chloroplasts, the parabasal Golgi body. an anterior vacuole, and scattered lipid droplets. Size: Cells elongate 8-18.5 µm x 6-11 µm Etymology: Greek nema (from haptonema) meaning thread, and me + theca with a sheath.
References:
Pienaar, R. N. & Birkhead, M. (1994). Ultrastructure of Prymnesium nemamethecum sp. nov. (Prymnesiophyceae). Journal of Phycology. 30: 291-300. gs
Prymnesium nemamethecum: Catalog entry compiled by Jeremy Young. Viewed: 17-2-2025