First Record of a Coelacanth Fish from the Middle Triassic Meride Limestone of Monte San Giorgio (Canton Ticino, Switzerland)

Paleontologists have uncovered the first fossil evidence of a coelacanth fish, specifically from the genus Heptanema, in the Middle Triassic Meride Limestone Formation at Monte San Giorgio. This discovery marks the first recorded occurrence of an actinistian (a lobe-finned fish) in this formation, offering new insights into the evolutionary history of these ancient vertebrates. The specimen, identified as Heptanema sp., shares key anatomical features with the previously described H. paradoxum from Northern Italy but exhibits differences likely attributable to ontogenetic stages. The study also attempts to elucidate the phylogenetic relationships of Heptanema, contributing to our understanding of coelacanth evolution during the Triassic period.

RENESTO, S. I. L. V. I. O., & STOCKAR, R. U. D. O. L. F. (2018). FIRST RECORD OF A COELACANTH FISH FROM THE MIDDLE TRIASSIC MERIDE LIMESTONE OF MONTE SAN GIORGIO (CANTON TICINO, SWITZERLAND). Rivista Italiana Di Paleontologia e Stratigrafia (Research In Paleontology and Stratigraphy), Vol 124, No 3 (2018). https://doi.org/10.13130/2039-4942/10771