Muricea Lamouroux, 1821

Breedy, Odalisca & Guzman, Hector M., 2016, A revision of the genus Muricea Lamouroux, 1821 (Anthozoa, Octocorallia) in the eastern Pacific. Part II, ZooKeys 581, pp. 1-69 : 6-7

Taxon classification Animalia Alcyonacea Plexauridae

Genus Muricea Lamouroux, 1821

Muricea Lamouroux, (pars.) 1821: 36; Blainville (pars.) 1834: 509; Ehrenberg (pars.) 1834: 134; Dana 1846: 673; Milne Edwards and Haime 1857: 142; Kölliker 1865: 135; Verrill 1868b: 411; Verrill 1869: 418-419, 450; Studer 1887: 58; Wright and Studer 1889: 93; Gorzawsky 1908: 8; Nutting 1910: 9; Kükenthal 1919: 835; 1924: 141; Riess 1929: 383-384; Aurivillius 1931: 102-104; Deichmann 1936: 99; Bayer 1956: F210; 1959: 12; 1961: 179-180; 1981: 930 (in key); 1994: 23-24; Tixier-Durivault 1970: 154; Harden 1979: 140; Hardee and Wicksten 1996: 127-128; Marques and Castro 1995: 162; Castro et al. 2010: 779.

Eumuricea (pars.) Verrill, 1869: 449; Riess 1929: 397.

Type species.

Muricea spicifera Lamouroux, 1821, by subsequent designation: Milne Edwards and Haime 1857. [ Muricea spicifera was later synonymised with Muricea muricata (Pallas, 1766) after Bayer 1961: 179-180].

Diagnosis

(based on Breedy and Guzman 2015). Colonies planar or multiplanar, bushy, arborescent, laterally branched, pinnately branched, dichotomous or with long flexible branches, with some occasional branch anastomosis. Branches and branchlets upward bending almost parallel, and with about the same thickness all along, frequently with slightly enlarged tips. Coenenchyme moderately to very thick (compared to other plexaurids) with a circle of longitudinal canals surrounding the axis and dividing the coenenchyme into a thin inner layer or axial sheath, and a thicker outer layer. Polyps fully retractile within prominent calyces longitudinally and closely placed all around the branches and branchlets, or spaced in loose spirals around the branches and branchlets. Calyces prominent, shelf-like or tubular, with prickly projecting spindles, longitudinally arranged. Base of the anthocodia without sclerites or with flat rods arranged in weakly differentiated collaret and points below the tentacles, or just transversely set along the neck zone of the polyp. Sclerites of the outer coenenchyme and of the calyx mostly long, unilateral spinous spindles, often massive, sculptured on inner surface by crowded complex tubercles and on outer surface by simple spines or prickles, and in some species with a few more or less prominent coarse, prickly projections. Spindles with laterally placed spinous or leaf-like processes are the dominant type in some species. Axial sheath composed of capstans, spindles, or oval forms, and undeveloped sclerites. Sclerite colours are white, various hues of yellow, amber, orange, purple and red. Anthocodials with lower hues.

Distribution.

From Cape Hatteras, North Carolina to Brazil, including Bahamas, Greater and Lesser Antilles, Gulf of México, and Caribbean islands ( Bayer 1961); in the eastern Pacific from southern California to Perú and presumably in Chile. The genus occurs at depths down to 200 m, but normally found less than 100 m. Muricea midas Bayer, 1959 is the deepest record for the genus in the western Atlantic ( Bayer 1959); and Muricea galapagensis Deichmann, 1941 in the eastern Pacific.

Remarks.

Based on calyx morphology, Verrill (1869) subdivided Muricea from the eastern Pacific in two main groups, one with tubular calyces (former Eumuricea , see Breedy and Guzman 2015) and the other with shelf-like calyces. As Breedy and Guzman (2015) noted, there are many intermediate forms referring to calyx structure and two extreme structures: tubular and shelf-like. For this reason the more sensible alternative was the division of the genus in two groups: the first, having tubular calyces (already revised by Breedy and Guzman 2015) and the second, having shelf-like calyces (in this work). The second group might be subdivided according to the branch thickness and the dominant type of sclerites of the outer coenenchyme and the calyx. The shelf-like structure of the calyx could vary from prickly prominent to slightly raised borders, and from raised adaxial borders to minute abaxial rims blending with the coenenchyme. Species groups based on the former characters are proposed herein.