Validating a molecular clock for nudibranchs-No fossils to the rescue

© 2024 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd..

Time calibrated phylogenies are typically reconstructed with fossil information but for soft-bodied marine invertebrates that lack hard parts, a fossil record is lacking. In these cases, biogeographic calibrations or the rates of divergence for related taxa are often used. Although nudibranch phylogenies have advanced with the input of molecular data, no study has derived a divergence rate for this diverse group of invertebrates. Here, we use an updated closure date for the Isthmus of Panama (2.8 Ma) to derive the first divergence rates for chromodorid nudibranchs using multigene data from a geminate pair with broad phylogeographic sampling. Examining the species Chromolaichma sedna (Marcus & Marcus, 1967), we uncover deep divergences among eastern Pacific and western Atlantic clades and we erect a new species designation for the latter (Chromolaichma hemera sp. nov.). Next, we discover extensive phylogeographic structure within C. hemera sp. nov. sensu lato, thereby refuting the hypothesis of a recent introduction. Lastly, we derive divergence rates for mitochondrial and nuclear loci that exceed known rates for other gastropods and we highlight significant rate heterogeneity both among markers and taxa. Together, these findings improve understanding of nudibranch systematics and provide rates useful to apply to divergence scenarios in this diverse group.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:14

Enthalten in:

Ecology and evolution - 14(2024), 2 vom: 11. Feb., Seite e11014

Sprache:

Englisch

Beteiligte Personen:

Layton, Kara K S [VerfasserIn]
Wilson, Nerida G [VerfasserIn]

Links:

Volltext

Themen:

Divergence rate
Geminate pairs
Journal Article
Molecular clock
Nudibranchia

Anmerkungen:

Date Revised 17.02.2024

published: Electronic-eCollection

Dryad: 10.5061/dryad.ns1rn8q08

Citation Status PubMed-not-MEDLINE

doi:

10.1002/ece3.11014

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM368522431