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Published on: August 31, 2018
Host shift and speciation in a coral-feeding nudibranch
Anuschka Faucci1, Robert J Toonen, Michael G Hadfield
1Kewalo Marine Laboratory, University of Hawaii at Manoa, 41 Ahui Street, Honolulu, HI 96813, USA. anuschka@hawaii.edu
Proceedings. Biological Sciences
|December 1, 2006
Summary
Marine nudibranchs show host specificity driving speciation. A study on Phestilla sea slugs reveals host shifts and cryptic speciation, highlighting the role of coral hosts in marine invertebrate evolution.
Area of Science:
- Marine Biology
- Evolutionary Biology
- Speciation Research
Background:
- Host preference is a key driver of ecological speciation in terrestrial systems, but its role in marine environments is less understood.
- Marine invertebrates, like the nudibranch genus Phestilla, often exhibit strong associations with specific host organisms, such as corals.
Purpose of the Study:
- To investigate the role of host specificity in the speciation of the nudibranch genus Phestilla.
- To disentangle the taxonomic status of Phestilla species using a phylogenetic approach.
- To explore potential host shifts and cryptic speciation within this genus.
Main Methods:
- Phylogenetic analysis using two mitochondrial genetic markers (cytochrome oxidase I and ribosomal 16S).
- Examination of Phestilla species from Guam, Palau, and Hawaii, focusing on their specific coral hosts (Porites, Goniopora, Tubastrea).
- Analysis of larval metamorphosis cues and reproductive behaviors tied to host corals.
Main Results:
- Phylogenetic trees confirmed most nominal Phestilla species as monophyletic clades.
- A potential host shift from Porites to Goniopora and Tubastrea was identified in sympatric Phestilla species.
- Highly divergent clades within Phestilla sp. 1 and Phestilla minor suggest cryptic speciation.
- A strong phylogenetic signal for coral hosts indicates their significant role in Phestilla speciation.
Conclusions:
- Host specificity and potential host shifts are significant mechanisms driving speciation in the marine nudibranch genus Phestilla.
- This study provides evidence for host-induced speciation in marine invertebrates.
- Cryptic speciation within Phestilla highlights the importance of considering host-parasite interactions in understanding marine biodiversity.
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