A growing body of knowledge on the diversity and evolution of intertidal isopods across different regions worldwide has enhanced our understanding on biological diversification at the poorly studied, yet vast, sea–land interface. High genetic divergences among numerous allopatric lineages have been identified within presumed single broadly distributed species.
The “sexy shrimp”
Coral reefs in all tropical oceans.
Specimens of
We found evidence for at least five cryptic lineages (9%–22%
- NSF-PAR ID:
- 10060476
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of Biogeography
- Volume:
- 45
- Issue:
- 6
- ISSN:
- 0305-0270
- Page Range / eLocation ID:
- p. 1275-1287
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Excirolana mayana is an intertidal isopod that is commonly found in sandy beaches throughout the Gulf of California. Its distribution in the Pacific extends from this basin to Colombia and in the Atlantic from Florida to Venezuela. Despite its broad distribution and ecological importance, its evolutionary history has been largely neglected. Herein, we examined phylogeographic patterns ofE. mayana in the Gulf of California and the Caribbean, based on maximum‐likelihood and Bayesian phylogenetic analyses ofDNA sequences from four mitochondrial genes (16SrDNA , 12SrDNA , cytochrome oxidase I gene, and cytochrome b gene). We compared the phylogeographic patterns ofE. mayana with those of the coastal isopodsLigia andExcirolana braziliensis (Gulf of California and Caribbean) andTylos (Gulf of California). We found highly divergent lineages in both, the Gulf of California and Caribbean, suggesting the presence of multiple species. We identified two instances of Atlantic–Pacific divergences. Some geographical structuring among the major clades found in the Caribbean is observed. Haplotypes from the Gulf of California form a monophyletic group sister to a lineage found in Venezuela. Phylogeographic patterns ofE. mayana in the Gulf of California differ from those observed inLigia andTylos in this region. Nonetheless, several clades ofE. mayana have similar distributions to clades of these two other isopod taxa. The high levels of cryptic diversity detected inE. mayana also pose challenges for the conservation of this isopod and its fragile environment, the sandy shores. -
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Location South America.
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Methods We sequenced four mt
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