Skull shapes of the Lissodelphininae: radiation, adaptation and asymmetry.

摘要: Within Delphinidae, the sub-family Lissodelphininae consists of 8 Southern Ocean species and 2 North Pacific species. is a result recent phylogenetic revisions based on molecular methods. Thus, morphological radiation within taxon has not been investigated previously. The ecologically diverse groups such as (1) Cephalorhynchus genus 4 small inhabiting coastal shelf waters, (2) robust in Lagenorhynchus with La. australis, offshore cruciger, pelagic obscurus obliquidens, (3) morphologically aberrant Lissodelphis. Here, shapes 164 skulls from adults all 10 were compared using 3-dimensional geometric morphometrics. supplemented by samples albirostris Delphinus delphis to obtain context for variation found subfamily. Principal components analysis was used map most important shape phylogeny. first component described an elongation rostrum, lateral dorsoventral compression neurocranium smaller temporal fossa. two Lissodelphis high extreme this spectrum, while cruciger heavisidii at low extreme. Along second component, isolated other its expanded concave facial profile. Shape supports gross relationships proposed studies. However, despite great diversity ecology external morphology subfamily, feeding apparatus modest, indicating similar mode across All their pattern skull asymmetry, but interestingly, narrowband frequency clicks (La. C. hectori) among asymmetric species, contradicting previous interpretations odontocete asymmetry. J. Morphol. 277:776-785, 2016. © 2016 Wiley Periodicals, Inc.