Nannotax3 - ntax_Farinacci - Imantonia

CATALOG - Imantonia

Folder trail: ntax_Farinacci -> Haptophytes -> Imantonia
Folders this level: Chrysocampanula, Chrysocapsa, Chrysochromulina, Chrysochromulinaceae, Chrysoculter, Corcontochrysis, Corymbellus, Diacronema, Dicrateria, Exanthemachrysis, Haptolina, Hyalolithus, Imantonia, Isochrysis, Monochrysis, Pavlomulina, Pavlomulinales, Pavlova, Pavlovaceae, Pavlovales, Petasaria, Phaeocystaceae, Phaeocystales, Phaeocystis, Platychrysis, Prymnesiaceae, Prymnesiales, Prymnesium> >>

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

Imantonia rotunda Reynolds 1974
= Dicrateria rotunda

Current identification/main database link: Dicrateria Parke 1949

Compiled data

Citation: Imantonia Reynolds 1974
Rank: Genus
Type species: Imantonia rotunda Reynolds 1974
Farinacci catalog page (& compiler): n/a
Current citation: Dicrateria Parke 1949

Original Description

Cells motile, not metabolic. Flagella two, smooth, homodynamic; haptonema not found. Chloroplasts parietal, golden brown, with embedded pyrenoids. Cell body bearing more or less circular scales with coarse radial fibrils on their proximal faces.


The name Imantonia,/i> was suggested by Dr M. Parke, in recognition of the very valuable contribution made by Professor Irene Manton, F.R.S., to our knowledge of the flagellates, and of the Haptophyceae in particular.

Extra details from original publication
Discussion: In its internal structure Imantonia agrees with the general concept of a haptophycean cell except for the absence of a haptonema. This is perhaps offset by the presence of the "peculiar" thickenings of the Golgi body which appear to be characteristic of this class. It closely resembles Dicrateria inornata Parke (Parke, 1949), but the chloroplasts are a little better defined and there is a tendency towards an indentation in the region of the flagella bases that is not evident in Dicrateria. Separation of the one from the other would be difficult with the light microscope, especially as they share the habit of the cells rotating while swimming and travelling in a constant direction for relatively long distances with the flagella more or less parallel behind the cell. Under the electron microscope Imantonia is immediately identified by its scales.

This flagellate appears to be differentiated from Isochrysis by the absence of a haptonema and of metaboly, and also the considerably difference in the type of scales. It is suggested that it should be placed in the Isochrysidales as a separate genus. 

Editors' Notes


Reynolds, N. (1974). Imantonia rotunda gen. et sp. nov., a new member of the Haptophyceae. British Phycological Journal. 9: 429-434. gs V O


Imantonia: Catalog entry compiled by Jeremy Young. Viewed: 7-10-2022

Taxon Search:
Advanced Search

Short stable page link: Go to to create a permanent copy of this page - citation notes
Link to WoRMS (World Register of Marine Species)

Comments (0)

No comments yet on this page. Please do add comments if you spot any problems, or have information to share

Add Comment

* Required information
Captcha Image
Powered by Commentics