title: Miocene Shark and Batoid Fauna from Nosy Makamby (Mahajanga Basin, Northwestern Madagascar).
abstract: Madagascar is well known for producing exceptional fossils. However, the record for selachians remains relatively poorly known. Paleontological reconnaissance on the island of Nosy Makamby, off northwest Madagascar, has produced a previously undescribed assemblage of Miocene fossils. Based on isolated teeth, ten taxonomic groups are identified: Otodus, Carcharhinus, Galeocerdo, Rhizoprionodon, Sphyrna, Hemipristis, Squatina, Rostroraja, Himantura and Myliobatidae. Six are newly described from Madagascar for the Cenozoic (Galeocerdo, Rhizoprionodon, Sphyrna, Squatina, Rostroraja and Himantura). In association with these specimens, remains of both invertebrates (e.g., corals, gastropods, bivalves) and vertebrates (e.g., bony fish, turtles, crocodylians, and sirenian mammals) were also recovered. The sedimentary facies are highly suggestive of a near-shore/coastal plain depositional environment. This faunal association shares similarities to contemporaneous sites reported from North America and Europe and gives a glimpse into the paleoenvironment of Madagascar's Miocene, suggesting that this region was warm, tropical shallow-water marine.
authors.affiliation: Département de Paléontologie et d'Anthropologie Biologique, Faculté des Sciences, Université d'Antananarivo 101, Antananarivo, Madagascar.
authors.forename: Tsiory H
authors.initials: TH
authors.lastname: Andrianavalona
authors.affiliation: Département de Paléontologie et d'Anthropologie Biologique, Faculté des Sciences, Université d'Antananarivo 101, Antananarivo, Madagascar.
authors.forename: Tolotra N
authors.initials: TN
authors.lastname: Ramihangihajason
authors.affiliation: Département de Paléontologie et d'Anthropologie Biologique, Faculté des Sciences, Université d'Antananarivo 101, Antananarivo, Madagascar.
authors.forename: Armand
authors.initials: A
authors.lastname: Rasoamiaramanana
authors.affiliation: Department of Earth Sciences, The Natural History Museum, Cromwell Road, London, SW7 5BD United Kingdom.
authors.forename: David J
authors.initials: DJ
authors.lastname: Ward
authors.affiliation: Department of Earth Sciences, University of Hong Kong, Pokfulam Road, Hong Kong, China.
authors.forename: Jason R
authors.initials: JR
authors.lastname: Ali
authors.affiliation: Department of Biological Sciences, Northern Illinois University, DeKalb, Illinois, United States of America.
authors.forename: Karen E
authors.initials: KE
authors.lastname: Samonds
mesh_terms: D000818:Animals; D005580:Fossils; D008270:Madagascar; D012754:Sharks / Q000033:anatomy & histology; D013112:Spiders / Q000033:anatomy & histology