Plexauridae Gray, 1859

Horvath, Elizabeth Anne, 2019, A review of gorgonian coral species (Cnidaria, Octocorallia, Alcyonacea) held in the Santa Barbara Museum of Natural History research collection: focus on species from Scleraxonia, Holaxonia, Calcaxonia - Part II: Species of Holaxonia, families Gorgoniidae and Plexauridae, ZooKeys 860, pp. 67-182 : 67

Family Plexauridae Gray, 1859

Diagnosis.

Colonies of very diverse form, generally with thick branches arising laterally, dichotomously (in some, pinnately). Polyps completely retractile or forming distinct calyces into which anthocodiae can be withdrawn. Axis with wide, chambered central chord; peripheral zone of loculated horny material, usually containing nonscleritic calcareous matter (common tendency toward heavy calcification of base in old colonies). Coenenchyme thick, perforated by system of longitudinal canals surrounding axis, delimiting outer coenenchymal layer from inner one (axial sheath), which differ in spiculation. Sclerites usually include some form of club; some with spindles only, oval bodies, rods or large quadriradiates.

Remarks.

Due to the highly variable nature of genera and species placed in this family, this is a complex, often confusing group of organisms. Ultimately, the best means to understanding this family was to study, in total, each of the several genera placed in it that are seen in California waters. In this part (Part II), emphasis has been placed on Chromoplexaura (formerly Euplexaura ) marki Williams, 2013a (part of a collective group referred to as the "red whip" species) and genera Muricea Lamouroux, 1821 and Placogorgia Studer, 1887 ( Wright and Studer 1889). While the genera Swiftia Duchassaing & Michelotti, 1864 and Thesea Duchassaing & Michelotti, 1860 are also included in this family, it was necessary to cover those with a more extensive study, discussed in Part III. The genus Thesea , as represented in California waters, additionally requires still further examination; ongoing study of that genus is in progress, and will require a separate discussion, to be presented at a later date.