The species have similar physical features - they are small, generally playful, blunt-nosed dolphins - but they are found in distinct geographical locations.
A recent phylogenetic analysis by May-Collado & Agnarsson (2006) indicates that two species traditionally assigned to the genus Lagenorhynchus, the Hourglass Dolphin L. cruciger and Peale's Dolphin L. australis are actually phylogenetically nested among the species of Cephalorhynchus, and they suggest that these two species should be transferred to the genus Cephalorhynchus. There is some acoustic and morphological support for this arrangement, at least with respect to Peale's Dolphin. According to Schevill & Watkins (1971), Peale's Dolphin and the Cephalorhynchus species are the only dolphins that do not whistle (no acoustic data are available for the Hourglass Dolphin). Peale's Dolphin also shares with several Cephalorhynchus species the possession of a distinct white "armpit" marking behind the pectoral fin.
Abundance and Spatial Distribution of Commerson's Dolphin (Cephalorhynchus Commersonii) at a Breeding Site: Ría Deseado, Patagonia, Argentina
Jan 01, 2013; AbstractAbundance and spatial distribution of the Commerson's dolphin (Cephalorhynchus com-mersonii) during spring and...
Using Static Acoustic Monitoring to Describe Echolocation Behaviour of Heaviside's Dolphins (Cephalorhynchus heavisidii) in Namibia
Apr 01, 2011; Abstract Static acoustic monitoring is a cost-effective, low-effort means of gathering large datasets on echolocation click...