Phylogenetic analysis of Dendronotus nudibranchs with emphasis on northeastern Pacific species

• Published in: Journal of Molluscan Studies
• Main Authors: Stout, Carla C., Pola, Marta, Valdés, Ángel
• Format: Text
• Language: English
• Published: Oxford University Press 2010
• Subjects: Research Papers; Arctic; Pacific; Beringia
• Online Access: http://mollus.oxfordjournals.org/cgi/content/short/76/4/367; https://doi.org/10.1093/mollus/eyq022

Molecular and morphological evidence suggests that the taxonomic status of several eastern Pacific species of Dendronotus needs a reassessment. Dendronotus diversicolor and D. albus are synonymized due to lack of genetic variation in the 16S rRNA gene and of any significant morphological differences. Dendronotus nanus and D. iris are also regarded as synonyms based on a reevaluation of ecological and morphological data. Finally, the name D. venustus is resurrected for eastern Pacific populations previously considered to be D. frondosus . Pacific D. venustus display consistent morphological and molecular differences from Atlantic D. frondosus . The molecular phylogeny presented here is not robust enough to shed light on the evolution and biogeography of Dendronotus , but preliminary evidence indicates that the Pacific species of Dendronotus are not a monophyletic group, because Arctic and Atlantic species are nested within them. The 16S rRNA genetic diversity within Dendronotus is very small compared to that of other related groups. These data, along with the comparatively large diversity of Dendronotus in the Pacific, suggest the possibility that relatively recent Arctic migration and vicariance along Beringia may have been involved in the evolution of this group.