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: Chrysochromulina apheles Moestrup&Thomsen 1986Taxonomic rank: speciesDescribed on page(s) : 594-601Standardised type level: 160_HOLOCENEType locality: Fig.6, from a culture based on a surface water sample from the Isefjord (55'44' N, 11'50' E) collected 15 November 1983 (22%, S, 5.5°C).Farinacci catalog page (& compiler): n/a Current citation: Chrysochromulina apheles Moestrup and Thomsen 1986
Original Description Cells variable in shape; some spherical and 3-4 µm in diameter (Figs. 2-4), others broadened (4-6 X 3 µm ) and at the same time flattened, concave on one side, convex on the other (Figs. 7, 8). The two flagella of unequal length (Fig. 5), the shorter flagellum 7-10 µm , the longer flagellum 11-15 µm , and inserted subapically on the ventral (concave) side of the cell. The haptonema substantially longer (20-40 µm ) and with a substructure of 6 microtubules. When coiled up, the haptonema forms approximately 10gyres. Two lateral chloroplasts, each with an immersed pyrenoid (Fig. 9). Periplast with two lunds of plate scales (Fig. 17) (Table 1). The larger scales circular, 0.20-0.25 µm in diameter; because of an irregular folding up of the diminutive raised rim these scales appear feebly angular in whole mounts. The scales show 19-21 radial ridges regularly arranged around a central area. This area contains four (occasionally two or three) larger per- forations separated by a cruciform thickening, the arms of which do not appear to be continuous with any of the radial ridges. Three or four concentric rings present between the peripheral rim and the central ring delimiting the four holes. The concentric rings closely packed, leaving slightly larger open areas near the central ring and at the scale periphery. The second type of plate scale very similar, but smaller, diameter 0.16-0.21 µm , and not angular in whole mounts (no raised rim present). Number of radial ridges 15- 17, with fewer concentric rings between the peripheral rim and the four central Size: Cells some spherical 3-4 µm, others broadened 4-6 X 3 µm. Larger scales circular, 0.20-0.25 µm in diameter. Smaller scales 0.16-0.21 µm. Etymology: Greek apheles, unostentatious Extra details from original publication Scales The scales of C. apheles are among the smallest hitherto described from any species of Chrysochromulina. Close examination has established the presence of two different types. Scale fields like that of Fig. 17 were therefore examined, and 100 scales of each type were measured. The results are given in Table 1 and Fig. 64. They show a slight overlap in scale size (Dmax is the largest diameter of the scale), the smaller scales measuring from 0.16 to 0.21 µm (mean 0.186 µm), the larger 0.20 to 0.25 µm (mean 0.224 µm). The scales from Thailand (Fig. 17B) are similar, while the few New Zealand scales found (Fig. 17A) were slightly bigger (0.23-0.26 and 0.26-0.27 µm, respectively). Whether this difference is real remains to be clarified (the New Zealand material was photographed on a different electron microscope).
The larger scales of C. apheles are not fortuitously arranged on the cell surface (Fig. 17). Each scale is encircled by six other scales positioned along three sets of lines which cross each other at an angle of approximately 60". The distance to the other scales (centre to centre) is approximately 0.3 µm. The smaller scales, some of which are pointed out in Fig. 17, do not form such regular patterns.
References:
Moestrup, Ø. & Thomsen, H. A. (1986). Ultrastructure and reconstruction of the flagellar apparatus in Chrysochromulina apheles sp. nov. (Prymnesiophyceae = Haptophyceae). Canadian Journal of Botany. 64: 593-610. gs
Chrysochromulina apheles: Catalog entry compiled by Jeremy Young. Viewed: 17-2-2025