An Eocene anchovy from Monte Bolca, Italy: The earliest known record for the family Engraulidae

Abstract

AbstractEngraulids, also known as anchovies, are a distinctive group of clupeoid fishes characterized by a series of derived morphological features of the snout and infraorbital bones, suspensorium and branchial arches. Although anchovies are very abundant today, they are scarcely represented in the fossil record. A new genus and species of anchovy, †Eoengraulis fasoloigen. et sp. nov., is described from the Eocene (late Ypresian,c. 50 Ma) locality of Monte Bolca, Italy. It is based on a single well-preserved articulated skeleton that exhibits a unique combination of characters that supports its recognition as a new genus of the family Engraulidae, including: nine branchiostegal rays; 40 preural vertebrae and 17 pairs of pleural ribs; pleural ribs – preural vertebrae ratio 0.42; seven supraneurals; dorsal-fin origin at about mid-length of the body; about 16 dorsal-fin rays; anal-fin origin slightly behind the base of the last dorsal-fin ray; 19 anal-fin rays; seven pelvic-fin rays; and small needle-like pre-pelvic scutes. The morphological structure of the single available specimen suggests that †Eoengraulis fasoloiis the sister taxon of all other engrauline taxa. †Eoengraulis fasoloiis the oldest member of the family Engraulidae known to date. This taxon suggests that the earliest phases of diversification of engrauline anchovies probably occurred in the coastal palaeobiotopes of the western Tethys during Eocene time.