Chromoplexaura cordellbankensis Williams and Breedy, sp. nov.

Figures 2–10.

HOLOTYPE.— CASIZ 228195; NOAA Sample SH-18-09-017; Cordell Bank, Cordell Bank National Marine Sanctuary, CBNMS Transect-127; ca. 51 km W. of Point Reyes Peninsula (38°03′ 15.465″N 123°28′48.072″W); 100.5 m depth; 08 August 2018; ROV Beagle (MARE) from FSV Bell M. Shimada (NOAA); one partial specimen (missing holdfast), wet–preserved in 95% ethanol.

PARATYPES.— CASIZ 228194 . NOAA Sample SH-18-09-016; Cordell Bank, Cordell Bank National Marine Sanctuary , CBNMS Transect-127; ca. 51 km W. of Point Reyes Peninsula, California, USA (38°03′15.915″N 123°28′49.874″W); 101.6 m depth; 08 August 2018; ROV Beagle (MARE) from FSV Bell M. Shimada (NOAA); one partial specimen (14 mm long branch fragment), wet-preserved in 95% ethanol . CASIZ 207519; La Cruz Canyon, Monterey Bay National Marine Sanctuary; California, USA (35.7694°N 121.4475°W); 106.8 m depth; 28 October 2018; coll. by ROV on board FSV Bell M. Shimada (NOAA); one whole specimen . CASIZ 207520; Anacapa Island, Channel Islands National Marine Sanctuary; California, USA (33.992°N 119.3722°W); 86 m depth; 31 October 2018; coll. by ROV on board FSV Bell M. Shimada (NOAA); one specimen in two pieces.

HABITAT AND DISTRIBUTION.— Found on rugose, rocky substrata often with conspicuous vertical relief, or on rounded boulders in boulder fields (Fig. 3). Distributed off the central and southern coasts of California, between 38.2° and 32.5°N latitude (Figs. 8–9); at mesophotic depths between 86 and 107 m. The type locality is Cordell Bank in the Cordell Bank National Marine Sanctuary, ca. 70 miles WNW of San Francisco, California, 100 m depth .

ETYMOLOGY.— The specific epithet is derived from Cordell Bank and the Latin suffix – ensis (belonging to); referring to the region of discovery of the new species and collection of the holotype – Cordell Bank National Marine Sanctuary.