TY - JOUR
T1 - ULTRASTRUCTURE OF GYMNODINIUM AUREOLUM (DINOPHYCEAE): TOWARD A FURTHER REDEFINITION OF GYMNODINIUM SENSU STRICTO
AU - Hansen, Gert
N1 - KEYWORDS
dinoflagellates • flagella • flagellar apparatus • Gymnodinium • nucleus • peduncle • phylogeny • ultrastructure
PY - 2001
Y1 - 2001
N2 - Examination of the ultrastucture of the unarmored dinoflagellate Gymnodinium aureolum (Hulburt) G. Hansen (syn: Gyrodinium aureolum Hulburt) revealed the presence of nuclear chambers, which are specialized differentiations of the nuclear envelope, similar to those described in the type species of Gymnodinium, G. fuscum (Ehrenberg) Stein and certain other Gymnodinium species. The nuclear pores were restricted to these chambers. In the flagellar apparatus a nuclear fibrous connective linked the longitudinal microtubular root and the nucleus. This structure had so far been observed only in Gymnodinium spp. and in the heterotrophic species Actiniscus pentasterias (Ehrenberg) Ehrenberg, Nematodinium armatum (Dogiel) Kofoid et Swezy and Polykrikos kofoidii Chatton. Another unusual feature of G. aureolum was the presence of a striated fiber in the longitudinal flagellum, a feature previously only found in Ceratium furca (Ehrenberg) Claparède et Lachmann and C. tripos (O.F. Müller) Nitzsch. Gymnodinium aureolum also possessed a prominent ventral protrusion associated with the peduncle and containing electron opaque material. It is concluded that G. aureolum belongs to the Gymnodinium sensu stricto group. This may be a temporary classification, however, because G. aureolum and its allies differ from the type species G. fuscum by the presence of a transverse striated root, striated collars, trichocysts, and a peduncle.
AB - Examination of the ultrastucture of the unarmored dinoflagellate Gymnodinium aureolum (Hulburt) G. Hansen (syn: Gyrodinium aureolum Hulburt) revealed the presence of nuclear chambers, which are specialized differentiations of the nuclear envelope, similar to those described in the type species of Gymnodinium, G. fuscum (Ehrenberg) Stein and certain other Gymnodinium species. The nuclear pores were restricted to these chambers. In the flagellar apparatus a nuclear fibrous connective linked the longitudinal microtubular root and the nucleus. This structure had so far been observed only in Gymnodinium spp. and in the heterotrophic species Actiniscus pentasterias (Ehrenberg) Ehrenberg, Nematodinium armatum (Dogiel) Kofoid et Swezy and Polykrikos kofoidii Chatton. Another unusual feature of G. aureolum was the presence of a striated fiber in the longitudinal flagellum, a feature previously only found in Ceratium furca (Ehrenberg) Claparède et Lachmann and C. tripos (O.F. Müller) Nitzsch. Gymnodinium aureolum also possessed a prominent ventral protrusion associated with the peduncle and containing electron opaque material. It is concluded that G. aureolum belongs to the Gymnodinium sensu stricto group. This may be a temporary classification, however, because G. aureolum and its allies differ from the type species G. fuscum by the presence of a transverse striated root, striated collars, trichocysts, and a peduncle.
U2 - 10.1046/j.1529-8817.2001.037004612.x
DO - 10.1046/j.1529-8817.2001.037004612.x
M3 - Journal article
SN - 0022-3646
VL - 37
SP - 612
EP - 624
JO - Journal of Phycology
JF - Journal of Phycology
IS - 4
ER -