Les ostracodes de l'Albien-Turonien moyen de la région d'Antsiranana (Nord Madagascar) : systématique, paléoécologie et paléobiogéographie [Albian-Middle Turonian ostracodes from the Antsiranana region (northern Madagascar): systematics, palaeoecology and palaeobiogeography]

Abstract

Ostracode associations from the Antsiranana region, formerly Diego-Suarez, in northern Madagascar have been studied at a taxonomic level. In the Albian-middle Turonian interval, 29 species belonging to 21 genera have been recognized, 10 new species, one new genus (Malagasyella) and a new sub-genus (Hemiglenocythere) have been erected. From a palaeoecological stand point, the succession of ostracode faunas shows a progressive shallowing trend, from basin-slope during Albian times to outer shelf during the Turonian. During these periods, the ostracode faunas of Madagascar show strong affinities with those of India (Rajasthan). This leads to a proposal for the existence of an indo-malagasy ostracode faunal province.

Keywords

• Ostracodes
• Madagascar
• Albian
• Cenomanian
• Turonian
• systematics
• palaeoecology
• palaeobiogeography