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Hidden diversity of Ctenophora revealed by new mitochondrial COI primers and sequences
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  • Lynne Christianson,
  • Shannon Johnson,
  • Darrin Schultz,
  • Steven Haddock
Lynne Christianson

Corresponding Author:[email protected]

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Shannon Johnson
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Darrin Schultz
University of California, Santa Cruz
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Steven Haddock
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[Definitive version of this article may be found here] The mitochondrial gene cytochrome-c-oxidase subunit 1 (COI) is useful in many taxa for phylogenetics, population genetics, metabarcoding, and rapid species identifications. However, the phylum Ctenophora (comb jellies) has historically been difficult to study due to divergent mitochondrial sequences and the corresponding inability to amplify COI with degenerate and standard COI ‘barcoding’ primers. As a result, there are very few COI sequences available for ctenophores, despite over 200 described species in the phylum. Here, we designed new primers and amplified the COI fragment from members of all major groups of ctenophores, including many undescribed species. Phylogenetic analyses of the resulting COI sequences revealed high diversity within many groups that was not evident from more conserved 18S rDNA sequences, in particular among the Lobata. The COI phylogenetic results also revealed unexpected community structure within the genus Bolinopsis, suggested new species within the genus Bathocyroe, and supported the ecological and morphological differences of some species such as Lampocteis cruentiventer and similar lobates (Lampocteis sp. ‘V’ stratified by depth, and ‘A’ differentiated by color). The newly described primers reported herein provide important tools to enable researchers to illuminate the diversity of ctenophores worldwide via quick molecular identifications, improve the ability to analyze environmental DNA by improving reference libraries and amplifications, and enable a new breadth of population genetic studies.
18 Feb 2021Submitted to Molecular Ecology Resources
05 Mar 2021Submission Checks Completed
05 Mar 2021Assigned to Editor
08 Mar 2021Reviewer(s) Assigned
28 Apr 2021Review(s) Completed, Editorial Evaluation Pending
24 May 2021Editorial Decision: Revise Minor
22 Jun 2021Review(s) Completed, Editorial Evaluation Pending
22 Jun 20211st Revision Received
28 Jun 2021Editorial Decision: Accept
Jan 2022Published in Molecular Ecology Resources volume 22 issue 1 on pages 283-294. 10.1111/1755-0998.13459