Eugorgia ampla ( Verrill, 1864 )

Breedy, Odalisca, Guzman, Hector M. & Vargas, Sergio, 2009, A revision of the genus Eugorgia Verrill, 1868 (Coelenterata: Octocorallia: Gorgoniidae), Zootaxa 2151, pp. 1-46 : 13-15

Eugorgia ampla ( Verrill, 1864)

Figure 5 , Plate 1A–C

Leptogorgia ampla Verrill, 1864: 32 .

Eugorgia (Gorgonia) ampla Verrill 1868a: 415

Eugorgia ampla Verrill 1868: 407 –408; Bielschowsky 1918: 44; Kükenthal 1924: 343; Stiasny 1951: 74 (dubious).

Material examined. Syntype series: MCZ 193a, dry, Margarita Bay, Baja California Sur, Mexico, no depth given, A. Garret, 1860. MCZ 193b, MCZ 36037, YPM 402 (fragment) dry, Margarita Bay, no depth given, A. Garret, 1860. MCZ 65167, dry, California Gulf, Sonora, Mexico, 9 April 1940, no further data. YPM 399, 400, dry, La Paz, Baja California Sur, 11–15 m, W.B. Rich, no date.

Other material: MEXICO: USNM 43012, dry, Magdalena Bay, Baja California, H.N. Lowe, no further data; USNM 8967, dry, Baja California, no further data. PANAMA: UCR 1129 ( STRI 97), dry, Islote Frailes, Azuero Peninsula, 5–30 m, H.M. Guzman, 12 December 2001. PERU: USNM 1007028A-B, Paita, Piura, W.L. Schmitt, no depth given, 8 October 1926.

Description. Colonies studied measure up to 56 cm in height, and 40.7 cm in width. Branching is irregularly dichotomous. Unbranched distal twigs can reach up to 8 cm in length, and 1 mm in diameter. Colour of the colonies is mostly orange, but lighter or darker hues are found. Polyps are distributed all around the branches, and crowd the surface. Polyp-mounds are slightly raised, almost flat, with round apertures 0.2–0.3 mm in diameter when preserved, larger when dried.

The illustrated syntype MCZ 193a is a colony (Plate 1) 35.3 cm in height and the same in width, with a circular holdfast, flabelliform, and growing upright. Three main branches arise from a short stem, about 10 mm in diameter. Unbranched twigs compressed proximally, 5–8 mm in diameter, more cylindrical, and slightly tapered at the ends, with rounded tips, and about 2–3 mm in diameter. They reach up to 5 cm in length. Colony is orange throughout. Several slightly marked longitudinal grooves occur along the thick branches, and near the base. The polyps are evenly distributed all around the branches (Plate 1B). Polypapertures are small, up to 0.5 mm in diameter, and crowd the surface (Plate 1B). Coenenchymal sclerites are all orange (Plate 1C). They are mostly double discs reaching up to 0.06 mm in length and 0.06 mm in width, several with complete discs which are mostly as long as broad and with flat disc-ends 0.015–0.025 mm in diameter; capstans reach up to 0.09 mm in length and 0.06 mm in width. Spindles are less abundant, up to 0.13 mm in length, and 0.05 mm in width, with 4–5 whorls of warty tubercles ( Fig. 5 ). In general, sclerites of the coenenchyme are mainly as in the illustrated specimen (MCZ 193a), with variation in the dominance of sclerite-types found in the samples. For example, in YPM 402, spindles with acute ends are more abundant than in MCZ 193a; in MCZ 36037, the double discs are more abundant than in MCZ 193a, both colonies (YPM 402 and MCZ 36037) were collected at the same locality during the same collection. Length of spindles can reach up to 0.15 mm in some samples. No anthocodial sclerites were obtained in the samples for study.

Distribution. Margarita Bay, La Paz, Baja California Sur; Gulf of California, Sonora, (type localities); Paita, Peru; and Azuero Peninsula, Panama. Bonin Islands (Ogasawara Islands), Japan is mentioned by Verrill (1864), but it is probably a mistaken locality. Stiasny (1951) reported a specimen of this species from the Sandwich Islands, but he remarked that the bad condition of the specimen made the identification uncertain.

Remarks. The species was originally described in 1864 in the genus Leptogorgia Milne Edwards & Haime, 1857 with doubts about the type locality, and without holotype designation. Nevertheless, the type series is consistent enough, to define the species.

Figures

FIGURE 5. Eugorgia ampla (MCZ 193), coenenchymal sclerites.