Anatomical and molecular markers confirm a new species of Tritonia Cuvier, 1797 from the Humboldt Current System

Uribe R.A.; Mendivil A.; Zavalaga F.; Sepúlveda F. · Marine Biodiversity (2026) · DOI: 10.1007/s12526-025-01616-y

Resumen

The genus Tritonia Cuvier, 1797 belongs to Tritoniidae, a diverse family of predatory nudibranchs found from tropical to Antarctic waters. Despite its ecological and neurobiological relevance, knowledge of this genus remains limited in the southeastern Pacific. Here, we formally describe Tritonia peruviana sp. nov., a common tritonid from the Peruvian coast, documented since 2006 in shallow waters associated with gorgonian corals. We employed an integrative approach combining detailed anatomical examinations and molecular analyses based on three genetic markers: mitochondrial COI and 16S rRNA, and nuclear H3. We also performed species delimitation analyses (ASAP, ABGD and bPTP), which supported T. peruviana sp. nov. as a distinct lineage based on two new COI sequences and three previously published as Tritonia sp 3. Phylogenetic analyses confirmed its separation from other Eastern Pacific congeners, particularly T. odhneri, T. exsulans and T. festiva. This species is distinguished externally by its large size, pinkish to reddish coloration, white longitudinal lines, and ring-shaped markings on the notum. Internally, it possesses smooth masticatory borders in the jaws, radular formula of 73–77 × 103–128.1.128–103 teeth, and a reproductive system with coiled ampulla, short and straight vas deferens, and conical penis. This study underscores the importance of further exploration in the Humboldt Current Ecosystem, where unique but overlooked species play a key role in shaping local marine ecosystems. © The Author(s), under exclusive licence to Senckenberg Gesellschaft für Naturforschung 2025.

Instituciones: Universidad Nacional Mayor de San Marcos