(…) Records have been published of three specimens of Phocaena dioptrica, all from the South Atlantic region.
The type was described by Lahille (1912) and was a pregnant and therefore adult female caught near Quilmes on the River Plate. A second female was captured in the Rio Santiago, and the third, a male, was taken at the same place about a year later.
Two more may new be added to the list of known specimens; one, secured by Sir Hubert Wilkins at South Georgia in 1923 during the Quest expedition and the other from the Falkland Islands. The latter was brought to me by a shepherd, G. Butler, who found it on the beach in a practically skeletonized condition. The sex could not be determined and the lower jaw and flippers were missing. The length from the tip of the snout to the notch of the flukes was 185.5 cm. Wilkins‘s animal was only 135.9 cm. (…)