Abstract
BackgroundShelled pteropods are planktonic gastropods that are potentially good indicators of the effects of ocean acidification. They also have high potential for the study of zooplankton evolution because they are metazoan plankton with a good fossil record. We investigated phenotypic and genetic variation in pteropods belonging to the genus Cuvierina in relation to their biogeographic distribution across the world’s oceans. We aimed to assess species boundaries and to reconstruct their evolutionary history.ResultsWe distinguished six morphotypes based on geometric morphometric analyses of shells from 926 museum and 113 fresh specimens. These morphotypes have distinct geographic distributions across the Atlantic, Pacific and Indian oceans, and belong to three major genetic clades based on COI and 28S DNA sequence data. Using a fossil-calibrated phylogeny, we estimated that these clades separated in the Late Oligocene and Early to Middle Miocene. We found evidence for ecological differentiation among all morphotypes based on ecological niche modelling with sea surface temperature, salinity and phytoplankton biomass as primary determinants. Across all analyses, we found highly congruent patterns of differentiation suggesting species level divergences between morphotypes. However, we also found distinct morphotypes (e.g. in the Atlantic Ocean) that were ecologically, but not genetically differentiated.ConclusionsGiven the distinct ecological and phenotypic specializations found among both described and undescribed Cuvierina taxa, they may not respond equally to future ocean changes and may not be equally sensitive to ocean acidification. Our findings support the view that ecological differentiation may be an important driving force in the speciation of zooplankton.Electronic supplementary materialThe online version of this article (doi:10.1186/s12862-015-0310-8) contains supplementary material, which is available to authorized users.
Highlights
Shelled pteropods are planktonic gastropods that are potentially good indicators of the effects of ocean acidification
This study focuses on the genus Cuvierina, an excellent model group for an integrative study of zooplankton because it has a worldwide distribution, it is abundantly present in museum collections, and has a well-described fossil record [25]
We further explored the population genetic structure of Cuvierina in the Atlantic Ocean based on the cytochrome oxidase I (COI) fragment using a total of 60 fresh specimens for which morphotypes were assigned (northern C. atlantica (N = 34), southern C. atlantica (N = 21) and central Atlantic C. cancapae (N = 5); Additional file 1)
Summary
Shelled pteropods are planktonic gastropods that are potentially good indicators of the effects of ocean acidification. Shelled pteropods (Mollusca, Gastropoda: Thecosomata) are potentially good bioindicators of the effects of ocean acidification, but their application as such is hampered by limited knowledge of their taxonomy, genetic diversity, ecology and distribution patterns. Pteropods are a group of heterobranch gastropods [1] that are a common component of the marine zooplankton They affect the ocean carbon cycle by producing aragonite shells that can accelerate the export of organic matter from. Recent studies suggest that marine plankton have higher evolutionary potential than originally thought and may be well poised for evolutionary responses to global change Calcifying plankton may be capable of rapid evolutionary as well as ecological responses to changing ocean conditions, including future changes driven by global warming and ocean acidification
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
