Data from: Dark ophiuroid biodiversity in a prospective abyssal mine field

The seafloor contains valuable mineral resources, including polymetallic
(or manganese) nodules that form on offshore abyssal plains. The largest
and most commercially attractive deposits are located in the Clarion
Clipperton Fracture Zone (CCZ), in the eastern Pacific Ocean (EP) between
Hawaii and Mexico, where testing of a mineral collection system is set to
start soon [1]. The requirement to establish pre-mining environmental
management plans has prompted numerous recent biodiversity and DNA
barcoding surveys across these remote regions. Here we map DNA sequences
from sampled ophiuroids (brittle-stars, including post-larvae) of the CCZ
and Peru Basin onto a substantial tree-of-life to show unprecedented
levels of abyssal ophiuroid phylogenetic diversity including at least
three ancient (>70 my), previously unknown clades. While
substantial dark (unobserved) biodiversity has been reported from various
microbial meta-barcoding projects [2, 3], our data shows that we have
considerably under-estimated the biodiversity of even the most conspicuous
mega-faunal invertebrates [4] of the EP abyssal plain.