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Recent exploration of Miocene-age deposits at Nosy Makamby, a small island ~50 km southwest of Mahajanga city in northwestern Madagascar, has led to the recovery of a large sample [82] of isolated barracuda teeth (Sphyraena sp.). in a tropical marine fauna that also includes diverse marine invertebrates, chondrichthyans, bony fishes, turtles, crocodylians, and sirenians. Characteristically for barracudas, the teeth are labiolingually flattened and fang-like with a broadly triangular and blade-like acuminate outline and sharply edged but unserrated cutting margins. These barracudas inhabited an environment that included coral reefs (based on fossil scleractinians) and seagrass beds (evidenced by the epiphytic benthic foraminifera Elphidium sp.). The relatively common occurrence of Miocene barracuda at Nosy Makamby corroborates the presence of a tropical marine ecosystem encircling Madagascar by the Miocene, likely similar overall to the environment found there today.

The Upper Cretaceous deposits of Madagascar have produced a rich terrestrial vertebrate fauna. Studies of Madagascar's endemic fossils and recent fauna have led to multiple hypotheses surrounding the origin of these clades on the island following its complete isolation 88 m.y.a. This report is the first published description of several representatives of fossil Elopomorpha (Teleostei) from the Late Cretaceous of Madagascar. Elopomorphs are primarily marine fishes and one of the most morphologically diverse groups within teleosts. Fragmentary fossil elopomorph elements often consist of tooth plates and vertebrae. The tooth plates and dentary reported here are diagnostic and identifiable to the generic classification of Albula, Egertonia, and Paralbula. The vertebrae are numerous and morphologically variable, which indicates the abundance and importance of elopomorphs in the coastal environment of Madagascar during the Late Cretaceous. Most Cretaceous elopomorphs are from localities in the Northern Hemisphere. While several species of Cretaceous elopomorphs are also found in the Southern Hemisphere, there are not as many in number or kind. These Madagascar fossils represent the oldest Albula and Paralbula fossils recorded from Gondwana, increasing their known spatial range. The Egertonia material described here represents one of the earliest occurrences of the genus, adding to its record during the Cretaceous of Gondwana. The presence of these fishes supports a more global distribution of these genera during the Late Cretaceous and a higher diversity of Elopomorpha in the Southern Hemisphere during the Mesozoic than previously documented.

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