Use of Traditional Tools and Micro-Computed Tomography for the Taxonomy of Carnivorous Bivalves from the Deep Waters of Southwestern Atlantic.

LEONEL PACHECO; VALERIA TESO; GUIDO PASTORINO

ZOOLOGICAL JOURNAL OF THE LINNEAN SOCIETY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2024

0024-4082

This study presents a morphological integrative analysis, incorporating both traditional techniques and micro-CT imaging, focused on species within the group commonly known as Septibranchia. Specimens deposited in malacological collections and samples collected aboard the R/Vs Puerto Deseado and Austral off Mar del Plata (~36°S), San Jorge Gulf (~46°), and MPA Namuncurá/Burdwood Bank area (~54°S), at depths ranging from 200 and 3000 m, are the subjects of this study. The outcomes include the identification of seven species. Among them, Cardiomya cleryana (d’Orbigny, 1846), C. knudseni (Allen & Morgan, 1981), Lyonsiella cf. fragilis Allen & Turner, 1974 and Cetoconcha spinulosa (Thiele, 1912), were previously collected in the study area. Cardiomya fragilissima (E A Smith, 1885), an Antarctic/sub-Antarctic species, extends its distribution up to 36°S. Two new species, Cetoconcha gigas sp. nov. and Lyonsiella tentaculata sp. nov. are described. A detailed description of the anatomical and conchological characters of each species and genera, along with insights into their geographic and bathymetric distribution, are provided. The microCT analysis contributed to a detailed anatomical inspection and revealed the presence of muscle bundles associated with the anterior portion of the visceral mass in the scanned specimens.