Reassessment and Relationships of †Scutatuspinosus itapagipensis (Teleostei, Clupeomorpha, †Ellimmichthyiformes) from the Neocomian of Recôncavo Basin, Northeastern Brazil

AUTOR(ES)
FONTE

An. Acad. Bras. Ciênc.

DATA DE PUBLICAÇÃO

06/02/2017

RESUMO

ABSTRACT Clupeomorphs are found in many assemblages of the northeastern Brazil, whose ages range from the Neocomian to Paleogene. Ten species were described. Among them †Scutatuspinosus itapagipensis, a torpedo-like fish found in shales of the Marfim Formation from Bahia, remains poorly known. At first it was positioned within †Scutatuspinosinae and indicated as closely related to †Diplomystus. Diagnoses for the subfamily and genus were based on certain characters masking relationships. Recently it was placed in †Ellimmichthyiformes, but its systematic position remains controversial. We furnish additional data and restorations together with a parsimony analysis with TNT program, using 60 unordered and unweighted characters from selected species of 13 genera. Our analysis produced 12 trees with 158 steps, a consistency index (CI) of 0.44 and retention index (RI) of 0.52. Low support indices still indicate insufficient data for many taxa and uncertain status for clades. According to the majority rule consensus, †Scutatuspinosus itapagipensis is placed within a “†paraclupeine” group with †Ezkutuberezi carmenae, †Ellimma branneri, †Ellimmichthys longicostatus, and †Paraclupea chetunguensis. Its minimum age and position among †paraclupeids indicate an early history of the group older than it was thought to be, supporting a biogeographical hypothesis based on generalized track from China to northeastern Brazil during the Lower Cretaceous.

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