Muricea robusta Verrill, 1864

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 : 55-59

Taxon classification Animalia Alcyonacea Plexauridae

Muricea robusta Verrill, 1864 Figures 43, 44

Muricea robusta Verrill, 1864: 36; Verrill 1869: 436-437; Kükenthal 1919: 752; Kükenthal 1924: 144; Riess 1929: 396-397; Harden 1979: 159.

Muricea robusta (pars.) Verrill 1866: 329.

Material.

Lectotype. YPM 1189a, dry, Acapulco, Mexico, A.E. Agassiz, 1859-1860, no more data. Paralectotypes. MÉXICO: MCZ 189; MZUC-ANT 195 (part of MCZ 189); YPM 1712 (figured fragment, Verrill 1869); YPM 1189b, dry, Acapulco, A.E. Agassiz, 1859-1860, no more data.

Description.

The lectotype is a 20 cm long and 10 cm wide colony with partially broken coenenchyme on some branches and with three naked distal axes (Fig. 43A). A slightly flattened stem, 11 mm in diameter, arises from an oval holdfast, about 4 cm in diameter (Fig. 43A). The branching is mostly dichotomous in one plane (Fig. 43A). The stem extends up to 36 mm and subdivides in two main branches, which bifurcate up to 5 times producing secondary branches and branchlets of less than 10 mm in diameter, all of similar diameter. The branches bifurcate at angles 45°-60°, 3.5-5 mm apart; the branchlets, that are short, are almost at right angles. The upper branches are curved inferring from the naked axes (Fig. 43A). Unbranched terminal ends are up to 16 mm long, with rounded tips, up to 8.5 mm in diameter. The naked unbranched terminal ends reach up to 70 mm long. No anastomosing branches are present. Axes are black and brownish at the tips. The calyces are all around the branches and close together. They are mostly low cones, 0.7-1.2 mm in height, with a slightly elevated margin around the polyps (Fig. 43B) that are more prominent towards the end of the branches (Fig. 43C). At the upper branches, the lower margin of the calyx curves upwards. The polyp apertures are large, and conspicuous. The coenenchyme is thick and granulose, composed of orange, brownish orange and light brown to whitish sclerites (Fig. 43 D–E). As in many other species in this genus, a division of sclerite layers is not clear and the coenenchyme is formed of a combination of several types of sclerite types intermingled. The coenenchymal and calycular sclerites are mostly the same type of spindles. The unilateral spinous spindles were rare in the samples, the larger sclerites are rather irregular spindles, bent or almost straight; the larger ones are covered with warts, almost up to the thorny end, and the others have a pronounced upper ridge of large spines (prickly spindles). The term cristate, suggested by Hickson (1928), could be applied to these sclerites (Fig. 44 A–B). They are 0.24-0.64 mm long and 0.08-0.26 mm wide. There are some small leaf-like spindles and irregular cristate forms (Fig. 44B). The axial sheath and the inner coenenchyme have some conspicuous sub-spheroidal sclerites densely covered with warty tubercles, warty spindles, and some cylinder-like sclerites, 0.30-0.40 mm long and 0.13-0.19 mm wide, and tuberculate capstans, 0.16-0.25 mm long and 0.08-0.12 mm wide (Fig. 44D). Anthocodial sclerites are orange warty rods and irregular forms, 0.043-0.15 mm long and 0.04-0.05 mm wide (Fig. 44C). Colour of the colony is brownish orange.

Variability.

The revised specimens are consistent with the lectotype.

Distribution.

Found in México in Venado Island by J.L. Carballo and reported for Cape San Lucas ( Harden 1979). Also found in Isla del Gallo, Colombia by Prahl et al. (1986) Type locality Acapulco, México.

Remarks.

The species was first mentioned by Verrill in 1864 and formerly described in 1869 with a specimen from Acapulco. We believe that Verrill’s type series are all fragments of the same colony; however, because this is not clear, herein we designated the specimen YPM 1189a as the lectotype of the species with the purpose of clearly establishing its taxonomic status.

Other material revised.

COLOMBIA: USNM 79466, dry, Isla del Gallo, near Tumacao, 0.5 m, H. von Prahl, 4 February 1982. MÉXICO: M12, dry, Venados Island, Mazatlan Bay, Sinaloa, 5-25 m, J.L. Carballo, 2 February 1999.