Scythes, sickles and other blades: Defining the diversity of pectoral fin morphotypes in Pachycormiformes

Publication date

2019-11-07

Authors

Liston, Jeff J.
Maltese, Anthony E.
Lambers, Paul H.
Delsate, Dominique
Harcourt-Smith, William E.H.
Van Heteren, Anneke H.

Editors

Advisors

Supervisors

Document Type

Article
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License

cc_by

Abstract

The traditional terminology of 'scythe' or 'sickle' shaped is observed to be flawed as an effective descriptor for pectoral fin shape in pachycormids. The diversity of pachycormid pectoral fin shapes is assessed across the 14 recognised genera that preserve complete pectoral fins, and improved terms are defined to more effectively describe their form, supported by anatomical observation and aspect ratio analysis of individual fins, and corroborated by landmark analysis. Three clear and distinct pectoral fin structural morphotypes emerge (falceform, gladiform, falcataform), reflecting a diversity of pachycormid lifestyles throughout the Mesozoic, from agile pursuit predator to slow-cruising suspension feeder.

Keywords

Aspect ratio, Bonnerichthys, Character creep, Leedsichthys, Lifestyle indicator, Pachycormidae, Pectoral fin morphotype, Planform, Protosphyraena, Saurostomus, General Neuroscience, General Biochemistry,Genetics and Molecular Biology, General Agricultural and Biological Sciences

Citation

Liston, J J, Maltese, A E, Lambers, P H, Delsate, D, Harcourt-Smith, W E H & Van Heteren, A H 2019, 'Scythes, sickles and other blades : Defining the diversity of pectoral fin morphotypes in Pachycormiformes', PeerJ, vol. 7, no. 11, e7675. https://doi.org/10.7717/peerj.7675