Morphology and biology of the Miocene butterflyfish Chaetodon ficheuri (Teleostei: Chaetodontidae)

Abstract

A detailed morphological analysis of the Miocene butterflyfish Chaetodon ficheuri Arambourg, 1927 is provided. The description is based on six specimens collected from the Upper Miocene (Messinian) diatomites of the Chelif Basin, in the vicinity of Oran, north-western Algeria. Based on the new information presented here, this species represents the only member of a new subgenus Arambourgchaetodon . This new subgenus is diagnosed by a unique combination of characters and belongs to the large clade formed by the Indo-Pacific subgenera of the genus Chaetodon . A morphofunctional analysis of the feeding structures suggests that C. ficheuri was an omnivore that probably browsed on a wide variety of benthic prey. Stratigraphical and palaeoenvironmental studies of the type localities of C. ficheuri indicate that this fish inhabited a wide variety of environments, from coral systems to deep coastal basins. The placement of C. ficheuri in the large Indo-Pacific clade of Chaetodon subgenera suggests that this fish represents a descendant (relict) of the Tethyan biota that survived in the Mediterranean up to the Messinian. The occurrences of butterflyfishes in the fossil record are listed and commented upon. © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 146 , 251‐267. ADDITIONAL KEYWORDS: Algeria ‐ fossil record ‐ Messinian ‐ osteology ‐ palaeobiogeography ‐ palaeoecology.