Saturday, September 19, 2020

[Mollusca • 2020] A Synoptic Review of the Family Dendronotidae (Nudibranchia): A Multilevel Organismal Diversity Approach


Dendronotus yrjargul 
Korshunova, Bakken, Grøtan, Johnson, Lundin & Martynov, 2020


Abstract
A synoptic review of the family Dendronotidae is presented based on morphological and molecular data. Three genera are recognized: DendronotusPseudobornella, and Cabangus gen. nov. Two new Dendronotus species are described, D. yrjargul sp. nov. and D. nordenskioeldi sp. nov., which reveal fine-scale differences. Dendronotus yrjargul sp. nov. from mid-Norway and the Arctic regions is a sister species to the North Pacific D. kalikal. These two species are showing clear morphological and ontogenetic differences but are close in genetic distance. In contrast, Dendronotus nordenskioeldi sp. nov. from the Laptev Sea is externally similar to the white morphs of D. lacteus or D. frondosus, but according to the molecular data and radular morphology it is distinct from any of its congenerics. Comparison of molecular and morphological data of D. niveus from the type locality (White Sea) and material from other localities with those from the American North Atlantic coast (type locality of D. elegans) reveals their substantial similarity. Therefore, D. niveus is considered a junior synonym of D. elegans. The present review of the family Dendronotidae contributes to a general discussion on the species concepts and on a recent proposal of multilevel organismal diversity.

Keywords: CabangusDendronotusPseudobornella; molecular phylogeny; species problem; taxonomy





Dendronotus yrjargul sp. nov.

Etymology. From Norwegian yrjar (=  old name for the type locality in Ørland) and gul (= yellow) meaning “yellow/golden of Ørland” in reference to the remarkable habitus of this species.

Distribution. From Norwegian Sea to Kara Sea. 


Dendronotus nordenskioeldi sp. nov. 

Etymology. In honour of Baron Nils Adolf Erik Nordenskiöld, outstanding Arctic explorer, geologist, and mineralogist. The Laptev Sea had been originally named “Nordenskiöld Sea”, after this Arctic explorer.

Distribution. So far known only from the Laptev Sea.


Representaives of the genus Dendronotus (living specimens).
 photographs by T. Korshunova, A. Martynov, K. Fletcher, D. Miller, Y. Fujiwara, K. Hasegawa, K. Sanamyan, N. Sanamyan, and O. Zimina


Genus Dendronotus Alder & Hancock, 1845 
Type species. Dendronotus frondosus (Ascanius, 1774)



Dendronotus albopunctatus Robilliard, 1972
Dendronotus albus MacFarland, 1966 
Dendronotus arcticus Korshunova, Sanamyan, Zimina, Fletcher & Martynov, 2016
Dendronotus bathyvela Martynov, Fujiwara, Tsuchida, R. Nakano, N. Sanamyan, K. Sanamyan, Fletcher & Korshunova, 2020
Dendronotus claguei Valdés, Lundsten & Wilson, 2018
Dendronotus comteti Valdés & Bouchet, 1998
Dendronotus dalli Bergh, 1879 
Dendronotus elegans Verrill, 1880 
Dendronotus europaeus Korshunova, Martynov, Bakken & Picton, 2017

Dendronotus frondosus (Ascanius, 1774) 
Dendronotus gracilis Baba, 1949 
Dendronotus iris Cooper, 1863 
Dendronotus jamsteci Martynov, Fujiwara, Tsuchida, R. Nakano, N. Sanamyan, K. Sanamyan, Fletcher & Korshunova, 2020
Dendronotus kalikal Ekimova, Korshunova, Shepetov, Neretina, Sanamyan & Martynov, 2015
Dendronotus kamchaticus Ekimova, Korshunova, Shepetov, Neretina, Sanamyan & Martynov, 2015
Dendronotus lacteus (Thompson, 1840) 
Dendronotus nanus Marcus & Marcus, 1967 

Dendronotus patricki Stout, Wilson & Valdés, 2011
Dendronotus primorjensis Martynov, Sanamyan & Korshunova, 2015
Dendronotus purpureus Bergh, 1879 
Dendronotus robilliardi Korshunova, Sanamyan, Zimina, Fletcher & Martynov, 2016
Dendronotus robustus Verrill, 1870 
Dendronotus rufus O’Donoghue, 1921 
Dendronotus subramosus MacFarland, 1966 
Dendronotus velifer G.O. Sars, 1878 
Dendronotus venustus MacFarland, 1966 
Dendronotus zakuro Martynov, Fujiwara, Tsuchida, R. Nakano, N. Sanamyan, K. Sanamyan, Fletcher & Korshunova, 2020


Genus Cabangus gen. nov. 
Type species. Dendronotus regius Pola & Stout, 2008

Etymology. From the Indonesian word “cabang” meaning “branch” in reference to this genus as “dendronotids of the tropics” and to respect the great contribution of the Indonesian fauna to global marine biodiversity (e.g., Hoeksema, 2007).

Cabangus noahi (Pola & Stout, 2008) comb. nov. 
Dendronotus noahi Pola & Stout, 2008: 55–63, figs 6A, B. 

Distribution. Papua New Guinea, north coast, outer barrier reef, Bagabag Island, Bismarck Sea.


Cabangus regius (Pola & Stout, 2008) comb. nov. 
Dendronotus regius Pola & Stout, 2008: 46– 54, Figs 1–5.

Distribution. Tropical Indo-west Pacific.


Genus Pseudobornella Baba, 1932 

Type species. P. orientalis Baba, 1932 
...


 Tatiana Korshunova, Torkild Bakken, Viktor V. Grøtan, Kjetil B. Johnson, Kennet Lundin and Alexander Martynov. 2020. A Synoptic Review of the Family Dendronotidae (Mollusca: Nudibranchia): A Multilevel Organismal Diversity Approach.   Contributions to Zoology. DOI: 10.1163/18759866-BJA10014

Den gyldne nakensneglen fra Ørland, en ny og ukjent art