Mesoplodon marus Gervais 1850

• Main Authors: Russell A. Mittermeier, Don E. Wilson
• Format: Other/Unknown Material
• Language: unknown
• Published: Lynx Edicions 2014
• Subjects: Biodiversity; Taxonomy; Animalia; Chordata; Mammalia; Cetacea; Hyperoodontidae; Mesoplodon; Mesoplodon marus; Bird Island; Baleine; The Throat; The Beak; North Atlantic
• Online Access: https://zenodo.org/record/6608565; https://doi.org/10.5281/zenodo.6608565

12. True’s Beaked Whale Mesoplodon marus French: Baleine-a-bec de True / German: True-Zweizahnwal / Spanish: Zifio de True Taxonomy. Mesoplodon mirus True, 1913, USA, “stranded in the outer bank of Bird Island Shoal in the harbor of Beaufort, North Carolina.” There are currently no recognized subspecies, but it is possible that the northern and southern forms are sufficiently distinct to be considered subspecies. Monotypic. Distribution. Anti-tropical distribution: N Atlantic Ocean, in a poorly defined region ranging from Ireland to the Canary Is in the E, and from Nova Scotia to Florida in the W, Southern Hemisphere, recorded in S Brazil, South Africa, Madagascar, and S Australia. Nevertheless, due to the small number of records, the full extent of its distribution in the Southern Hemisphere is unclear. Descriptive notes. Total length 480-540 cm; weight 1000-1400 kg. Female True’s Beaked Whales may beslightly larger than males. Body is spindle-shaped, with greatest girth around its midpoint. Flukes are wide in relation to body length, and tailstock is compressed laterally. Dorsal fin is small and set approximately two-thirds the distance between tip of the beak and end of the tail. Coloration differs between True’s Beaked Whales found in the North Atlantic Ocean and those found in the Southern Hemisphere. In the Northern Hemisphere form, individuals are medium to dark gray on top and paler underneath, with a dark patch just behind the eye. In the Southern Hemisphere form, there is an additional white or pale area on each side on the flank from the dorsal fin back toward flukes. Adult males may have a number of long white lines that are unpigmented scars from aggressive male-male interactions. Rostrum and lowerjaw form a short but distinct beak, and there are two grooves on the throat. Adult males have a pair of conical tusks at the tip of the rostrum; these may become heavily worn over time. Habitat. Primarily waters greater than 200 m deep. In common with other species of Mesoplodon, True’s Beaked Whales may ...