2.1 | Sample Collection
Ctenophores were primarily collected by remotely operated vehicles (ROVs), blue-water SCUBA diving, and midwater trawls, along with contributions from collaborators around the globe (Table S1).Tissue samples for genomic DNA or RNA were flash frozen in liquid nitrogen, then stored at -80°C. Genomic DNA was isolated from frozen samples using the DNeasy DNA Blood and Tissue kit (Qiagen, Germantown, MD) or the Monarch Genomic DNA Purification Kit (New England Biolabs, Ipswich, MA) according to the manufacturers’ directions. When possible, multiple individuals within a species from different localities and depths were separately amplified and sequenced.