Copepod-infested Bathonian (Middle Jurassic) echinoids from northern France

Titre Copepod-infested Bathonian (Middle Jurassic) echinoids from northern France
Titre court Copepod-infested Bathonian (Middle Jurassic) echinoids from northern France
Type de document article
Auteur(s) Radwanska, U.
Poirot, E.
Date 2010
Titre de la publication Acta Geologica Polonica
Volume vol. 60
4
N° de page(s) 549-555
Résumé New examples of Bathonian (Middle Jurassic) parasitic exocysts on acrosaleniid echinoid tests are recorded from northern France. These exocysts can be attributed to the life activity of copepod crustaceans and are considered to have been formed as a result of copepod larval settlement in these echinoids by way of the gonopores. Sexual dimorphism is recognised in copepod-infested Acrosalenia spinosa L. Agassiz, 1840, on the basis of size and position of gonopores, those in females being larger and wider apart, those in males smaller and situated subcentrally. The previous stratigraphic range of copepod cysts of this type (i.e., Middle Oxfordian to Middle Kimmeridgian) can now be extended down to the base of the Bathonian (convergens Subzone).
ISSN 0001-5709
Langue Anglais
Collection Notre bibliothèque
Radwanska, U. and Poirot, E., 2010. Copepod-infested Bathonian (Middle Jurassic) echinoids from northern France. Acta Geologica Polonica. vol. 60 n° 4. p. 549-555. ISSN : 0001-5709.

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