2026-10-14T08:18:13Z https://api.figshare.com/v2/oai

oai:figshare.com:article/32132903 2026-09-18T10:38:10Z category_13 category_16 category_24 category_272 category_39 category_734 category_62 portal_87 item_type_3 month_year_09_2026

Taxonomic and morphometric revision of Alopiidae (Lamniformes) shark family: a qualitative holistic approach based on dental characters Danillo Santos Granzotti (23816450) Yuri Modesto Alves (25071633) Hugo Bampi (23816456) Genetics Physiology Evolutionary Biology Environmental Sciences not elsewhere classified Ecology Biological Sciences not elsewhere classified Marine Biology Palaeontology Elasmobranchii dentition Alopiidae geometric morphometrics taxonomy Dr J. Cooper, Swansea University, UK <p>This study investigates the taxonomic boundaries and internal relationships within the family Alopiidae, the thresher sharks, which are distinguished by their elongated upper caudal fins. While only three extant species are recognised, the fossil record suggests greater diversity, though classification remains contentious due to a reliance on isolated and interpreted dental fossils. To address this, the research combines quantitative geometric morphometric analysis of tooth shape with qualitative assessments of diagnostic features across both extant and putative fossil alopiid genera. Analysis of a comprehensive dataset of fossil tooth images reveals that the current taxonomic framework lacks strong morphometric support. Notably, the fossil genus †‘Anotodus’ retroflexus exhibits strong morphometric similarity to the lamnid shark <i>Isurus oxyrhinicus</i>, yet retains key qualitative features that support its placement within Alopiidae, suggesting convergent evolution. Conversely, the Cretaceous genus †Paranomotodon aligns with Alopiidae in both morphometric and qualitative analyses, affirming its familial inclusion. The genus †Trigonotodus displays a unfique combination of traits, placing it ambiguously between Alopiidae and Otodontidae, and is best retained as Lamniformes <i>incertae sedis</i>. This work underscores the critical need for integrating qualitative and quantitative approaches, demonstrating that morphometric similarity alone is insufficient for taxonomic revision without corroborating qualitative evidence.</p> 2026-09-18T10:38:10Z Dataset Dataset 10.6084/m9.figshare.32132903.v2 https://figshare.com/articles/dataset/Taxonomic_and_morphometric_revision_of_Alopiidae_Lamniformes_shark_family_a_qualitative_holistic_approach_based_on_dental_characters/32132903 CC BY 4.0