RADseq of Diopatra biscayensis
DNA was extracted from individuals of D. biscayensis using an antenna or branchius using the Qiagen DNeasy Blood & Tissue Kit following manufacturers protocols. Quality of the DNA was subsequently checked on a 1% TAE gel and a Qubit 2.0 fluorometer. The 2b-RAD protocol of Wang et al. (2012) which employs the restriction enzyme AlfI was used to generate a reduced representation library (using a 1/16th adaptor ligation reduction scheme).  Sample libraries were dual-barcoded and sent to Hudson Alpha Institute for Biotechnology (Huntsville, Alabama) for sequencing on an Illumina HiSeq using 50 bp single-end chemistry.