Abstract
Aim
The presence of cryptic species causes significant challenges to biodiversity assessment and biological resources management. Here, we investigate the genetic structure and biogeographical patterns of a complex ophiuroid species as a case study.
Location
Yellow Sea and Funka Bay in the Western Pacific Ocean, Bering Sea in the Arctic Ocean and Barents Sea in the Atlantic Ocean.
Taxon
The circumpolar ophiuroid Ophiura sarsii, a common benthic species across the Arctic seas, has at least two cryptic lineages.
Methods
To better understand the genetic structures and the underlying evolutionary processes in the O. sarsii species complex, we compared the genome-wide single nucleotide polymorphism (SNP) data and COI of five geographical populations across the northern Pacific, Arctic and Atlantic Oceans using the 2b-RAD sequencing approach.
Results
Results clearly showed three highly diverged evolutionary lineages: northern Pacific lineage (O. sarsii vadicola), Pacific-Arctic lineage (LA) and Atlantic lineage (LB). The divMigrate analysis revealed significant gene flow within O. sarsii vadicola populations and O. sarsii LA populations, but no cross-species gene flow. Demographic analysis was used to estimate their historical divergence, in which the differentiation of O. sarsii vadicola predated that of the other two lineages of O. sarsii. Molecular dating resulted in an estimation of their divergence events between 3.88 and 1.67 Ma at Pliocene–Pleistocene using COI. Functional analysis revealed several enriched signalling pathways, potentially involved in ophiuroids' environmental adaptation.
Main Conclusions
Our study suggests three lineages of the cryptic species O. sarsii could split into at least two genetic species, including O. sarsii vadicola, North Pacific–Arctic and Atlantic O. sarsii. The hidden evolutionary trajectory is uncovered for the O. sarsii complex, shaped by paleoclimate and ocean currents. We emphasise the need for genome-wide SNP applications to understand the ophiuroid biodiversity and contribute to conservation in the Pacific–Arctic region.
The presence of cryptic species causes significant challenges to biodiversity assessment and biological resources management. Here, we investigate the genetic structure and biogeographical patterns of a complex ophiuroid species as a case study.
Location
Yellow Sea and Funka Bay in the Western Pacific Ocean, Bering Sea in the Arctic Ocean and Barents Sea in the Atlantic Ocean.
Taxon
The circumpolar ophiuroid Ophiura sarsii, a common benthic species across the Arctic seas, has at least two cryptic lineages.
Methods
To better understand the genetic structures and the underlying evolutionary processes in the O. sarsii species complex, we compared the genome-wide single nucleotide polymorphism (SNP) data and COI of five geographical populations across the northern Pacific, Arctic and Atlantic Oceans using the 2b-RAD sequencing approach.
Results
Results clearly showed three highly diverged evolutionary lineages: northern Pacific lineage (O. sarsii vadicola), Pacific-Arctic lineage (LA) and Atlantic lineage (LB). The divMigrate analysis revealed significant gene flow within O. sarsii vadicola populations and O. sarsii LA populations, but no cross-species gene flow. Demographic analysis was used to estimate their historical divergence, in which the differentiation of O. sarsii vadicola predated that of the other two lineages of O. sarsii. Molecular dating resulted in an estimation of their divergence events between 3.88 and 1.67 Ma at Pliocene–Pleistocene using COI. Functional analysis revealed several enriched signalling pathways, potentially involved in ophiuroids' environmental adaptation.
Main Conclusions
Our study suggests three lineages of the cryptic species O. sarsii could split into at least two genetic species, including O. sarsii vadicola, North Pacific–Arctic and Atlantic O. sarsii. The hidden evolutionary trajectory is uncovered for the O. sarsii complex, shaped by paleoclimate and ocean currents. We emphasise the need for genome-wide SNP applications to understand the ophiuroid biodiversity and contribute to conservation in the Pacific–Arctic region.
| Original language | English |
|---|---|
| Article number | e15184 |
| Journal | Journal of Biogeography |
| Volume | 52 |
| Issue number | 10 |
| Early online date | 27 Jun 2025 |
| DOIs | |
| Publication status | Published - Oct 2025 |
Bibliographical note
Publisher Copyright:© 2025 John Wiley & Sons Ltd.
Funding
Funding: This work was supported by National Natural Science Foundation of China, 42176135, 41706190. Thanks to Prof. Tetsuya Takatsu for providing samples of O. sarsii vadicola and O. sarsii from Funka Bay. Other specimens were sampled thanks to the cruise of the 10th Chinese National Arctic Research Expedition and the 2018 Yellow Sea Cruise. No permits were required for specimens used in this study. This work was supported by the National Natural Science Foundation of China (42176135, 41706190).