Nannotax3 - ntax_Farinacci - Chrysochromulina campanulifera

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 campanulifera Manton&Leadbeater 1974

Farinacci catalog page (& compiler): n/a

Current citation: Chrysochromulina campanulifera Manton and Leadbeater 1974

Cellula circiter 10µm diam. vel ultra, ephippiomorpha, haptonemate in statu retracto inter lobos apicales incurvos abscondito. Flagella aequalia, circiter 25 μm longa. Haptonema multo longuis, ut in C. strobilo aliisque speciebus eae affinibus 6 microtubulis percursum. Chloroplasti duo laterales, quisque pyrenoides internum binis thylacoidibus contractis transectum fovens. Periplastus duo strata squamarum mucilagine copiose induta praebens: squama strati exterioris campanuliformis, margine credo, Iateribus praeterea subcurve divergentibus fenestris translucidis in duas (raro tres vel unam) series dispositis una linens transversas pellucidas efficientibus ornatis, basi plana vel rotundata non conica nullum stipitem praebente sed medio incrassata intra protuberante, plerumque 0.18 x 0.18 μm magna, interdum major (ad 0.22 μm lata, 0.18 μm alta) vel minor (0.18 µm lata, 0.12 μm alta); squama strati interioris plana, ovalis, 0.28 x 0.22 µm magna, carinula paulum incrassato-elevata taeniam tenuem marginalem radiatim striatam limitante cincta, medio nota cruciformi incrassata manifesta ornata. Vacuola alimentaria frequentia, plerumque materiem detritam continienta.

Species mense. Julio anni 1971 ut anni 1972 in utroque mari ultimam paeninsulam Jutlandicam alluente crebra (practrea adhuc nusquam inventa), figuris hic appositis 70-73 omnibus eandem cellulam monstrantibus typificata.

Cells approx 10 x 10 µm; flagella 25 µm long; outer layer of bell-shaped scales ca 0.2 µm; inner layer of body scales oval 0.28 x 0.22 µm.

This description is incomplete in certain details. Thus the exact length of the haptonema can only be specified in general terms. A section such as that in Fig. 72 includes no more than part of the helix and though the whole mount in Figs. 68, 69 is complete, the preservation is not good enough to permit definitive counting of the number of gyres though a rough estimate of "not less than 20" can be made. This is nonetheless sufficient to indicate a haptonema substantially longer than the flagella, as in the closely related C. strobilus, C. cymbium and C. camella (LEADBEATER & Manton 1969a, 1969b), though further observations, preferably on living cells, are still needed to confirm and establish this more accurately.

Some uncertainty also pertains to the cell size since there is the usual discrepancy between measurements on dried cells (8 x 8 μm in Fig. 67 and 7 x 7 μm in Fig. 68) compared with those on sections. Even the latter could be too small since it is rarely possible to know whether a given section is exactly median and therefore registering the widest possible dimensions or not. The measurements actually included in the diagnosis (10 x 10 μm) may therefore eventually need to be emended in the upward direction. On the other hand, the range of sizes among scales, as illustrated in Figs. 82-84, represent genuine differences between individual specimens of a kind that can sometimes be encountered in adjacent cells in one preparation (Fig. 76). Our reason for including them all within one taxonomic diagnosis is that in spite of these differcnces they share the characteristic shape distinguishing them from other members of the group present in the same blocks, as for example C. strobilus illustrated in Figs. 82-84. Moreover in spite of their observed differences of size all the scales attributed here to C. campanulifera fall within a size range not previously represented in the group all being smaller than the scales of C. camella but larger than those of C. cymbium or C. strobilus. This suggests that in spite of clonal differences in surface patterning (summarised in text-fig. 2), which may or may not prove to be genetically stable, there is no reason to attribute the taxonomically significant characters to the action of transient environmental factors.

The relatively large cell size is in this case perhaps associated with active predation since traces of relatively intact alien protoplasts, that seem likely to have been alive before ingestion, can sometimes be found in food vacuoles. Detritus is nevertheless more usual and pellets up to 0.4 µm in diameter have been sectioned. The particular food vacuole included in Fig. 71 on the other hand contains a partly decomposed alien haptonema, doubtless ingested as organic detritus.

The very copious mucilage present all over the cell surface-is a serious impediment to observation of scale patterning in whole mounts. These usually appear as in Fig. 75 in which only the outer edges of cups can he discerned through the mucilage, without any sign of the presence of underlying plates. To remove the mucilage requires more vigorous washing than was applied when we were concerned to retain intact cells still showing their appendages, a task which for some reason proved difficult. A renewed search for this species in the type locality with this need in mind might therefore prove rewarding.

References:

Manton, I. & Leadbeater, B. S. C. (1974). Fine-structural observations on six species of Chrysochromulina from wild Danish marine nanoplankton, including a description of C. campanulifera sp. nov. and a preliminary summary of the nanoplankton as a whole. Biologiske Skrifter, Kongelige Danske Videnskabernes Selskab. 20: 1-26. gs O

CATALOG - Chrysochromulina campanulifera

References:

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