Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

DEEPEND: Once Bitten, Twice Shy: A Cryptic Species of Sloane's Viperfish (Chauliodus sloani) Discovered in the Mesopelagic Waters of the Gulf of Mexico

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Gulf of Mexico Oil Spill & Ecosystem Science Conference, New Orleans, LA, February 6-9, 2017

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The deep-oceanic Gulf of Mexico (GoM) is one the highest diversity pelagic ecosystems in the world. The diversity GoM deep-sea fish fauna is exceptional, and rivals or exceeds that found in other deep-pelagic ecosystems. While some species of deep-sea fishes appear to be exclusively found in the GoM, a large portion of the deep-sea fish fauna is represented by species found in other basins. However, genetic methods have begun to unravel some of this traditional taxonomy, and have revealed unanticipated diversity and endemism in the deep-pelagic of the GoM. This is in the form of cryptic species, those that are closely related and morphologically similar to described taxa, but for which genetic data has identified as being novel lineages. One example is Chauliodus sloani or Sloane’s viperfish, a mesopelagic predatory fish found throughout the earth’s deep-pelagic waters. Our genetic surveys of viperfish samples using the mitochondrial barcoding gene COI has revealed two deeply divergent viperfish linages co-existing in the GoM, one apparently endemic to the GoM. These fishes live in sympatry, with no obvious ecological or morphological differences separating them. Nonetheless, there is over 11% pairwise sequence divergence between the two lineages, and species delimitation methods have identified them as two independently evolving lineages. Looking towards the future, we plan to perform further morphological and genetic work to better tease apart the evolutionary mechanisms responsible for the generation of this novel biodiversity and the maintenance of species boundaries in the deep-sea. This, in turn, will further our understanding of the generation of biodiversity in the GoM.

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Also presented at the Barry University STEM Research Symposium, Miami Shores, Florida, April 12, 2017.