Análisis morfológico y comparativo de los dentículos dérmicos de cinco especies de tiburones desembarcados en Ecuador

Néstor Javier  Bailón-Vera; Walter Gilberto  Tigrero-González

doi:10.56124/yaku.v8i15.002

Authors

Néstor Javier Bailón-Vera Universidad Estatal Península de Santa Elena, Ecuador.
Walter Gilberto Tigrero-González Ministerio de Producción, Comercio Exterior, Inversiones y Pesca, Ecuador.

DOI:

https://doi.org/10.56124/yaku.v8i15.002

Keywords:

Dermal denticles, Bycatch, Ecuador, Taxonomy

Abstract

Taxonomic identification of sharks in artisanal fishing contexts poses significant challenges, especially when specimens are landed fragmented or lack evident diagnostic structures. This study proposes the morphological characterization of dermal denticles as a complementary tool for species identification of five sharks commonly landed at the Santa Rosa artisanal port, Ecuador: Alopias pelagicus, Alopias superciliosus, Prionace glauca, Isurus oxyrinchus, and Carcharhinus falciformis. Skin biopsies were collected from the mid-dorsal region of commercially sized individuals following standardized protocols. Observations were conducted using stereomicroscopy and optical microscopy, focusing on the morphology of the denticle crown. Distinctive features such as the number and shape of cusps, presence of longitudinal ridges, and surface texture were described. Morphometric parameters such as aspect ratio (AR = length/width) were calculated, revealing significant differences among species. A. superciliosus and I. oxyrinchus showed the highest AR values (>1.1), associated with elongated forms, whereas C. falciformis exhibited broader denticles (AR = 0.86). These morphological variations are related to swimming style and functional adaptations, reflecting patterns consistent with previous reports from other regions. The results highlight the taxonomic value of dermal denticles and their application in inspection, traceability, and control of the illegal trade of shark-derived products, especially when other structures are not available. We recommend incorporating this tool into monitoring and fisheries forensic analysis protocols in Ecuador.

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