Pacifigorgia sculpta, Breedy, Odalisca & Guzman, Hector M., 2004

Breedy, Odalisca & Guzman, Hector M., 2004, New species of the gorgoniian genus Pacifigorgia (Coelenterata: Octocorallia: Gorgoniidae) from Pacific Panama, Zootaxa 541, pp. 1-15 : 12-14

Pacifigorgia sculpta , new species

( Figs. 1 G–H, 5A–C)

Material examined. Holotype: UCR 1497, Islote Frailes, Península de Azuero, 10–30 m, H.M. Guzman, 9 December 2001.

Paratypes: MCZ 57053, Islote Frailes, 10–30 m, H.M. Guzman, 9 December 2001; STRI 389–390, Isla Jicarita, Gulf of Chiriquí, 20 m, H.M. Guzman, 8 August 2002; STRI 410–412, Isla Seca Grande, Gulf of Chiriquí, 20 m, H.M. Guzman and O. Breedy, 26 August 2002; STRI 454, Isla Roncadores, Gulf of Chiriquí, 10–20 m, H.M. Guzman and O. Breedy, 30 August 2002; STRI 476, 482, 497, Bajo Foul, Península de Azuero, 15 m, H.M. Guzman, 11 April 2003; STRI 602, Islote Frailes, 20 m, H.M. Guzman, 1 May 2003; STRI 628, Roca Catedral, 5–15 m, H.M. Guzman, 3 May 2003; STRI 650, Bajo Brincanco, Gulf of Chiriquí, 10–30 m, H.M. Guzman, 5 May 2003; STRI 718, 721–722, 729– 731, 734, Bajo Trollope, Gulf of Panama, 10–20 m, H.M. Guzman, 6 August 2003; UCR 1037, 1042, Islote Frailes, 10–20 m, H.M. Guzman, 6 August 2003; UCR 1171, 1173, 1175, 1177, 1179, 1181, 1183, 1505, Roca Niagara, Gulf of Panama, 10–20 m, H.M. Guzman, 13 December 2001; UCR 1361–1365, 1506, Piedra Hacha, 20–30 m, H.M. Guzman, 22 April 2002; UCR 1498, Isla Jicarita, Gulf of Chiriquí, 20–30 m, H.M. Guzman, 19 April 2002; UCR 1499, 1501, 1508, Islote Frailes, 10–30 m, H.M. Guzman, 12 December 2001.

Description. Colonies wider than high, up to 120 mm in height and 200 mm in width. Most of the colonies are composed of a single fan, but some have two or three secondary fans that radiate from different parts of the main fan and grow parallel. Colour when preserved or alive is dark orange or reddish brown with lighter hues at the tips, and light ochre when dry. Colonies have a large holdfasts, and fans grow directly from this or sprout from short stems (up to 7 mm in diameter). Network is irregular. Meshes are very open (about 2–3 meshes/cm²), mostly elongate, up to 45 mm in length, and 25 mm in width. Mesh branches are squarish in section, from 3 mm thick at their base to 1 mm at their tips. No midribs cross the fans, just some thick branches (up to 6 mm in diameter) at the base that diminish and merge with the fan. End­branchlets are long; up to 25 mm in length. Freetwigs are abundant, up to 15 mm in length; they stick out from the fans, twist and grow parallel as free branches. The polyps are retracted within dome­shaped coenenchymal mounds, which are prominent and arranged mostly in pairs along the sides of the branches. In dry specimens, the lateral distribution of the calices is more evident, and bands of coenenchyme are clear between them. The polyps are yellowish with rods arranged in strong, thick points, with some untidily arranged intermediate rods. The anthocodial rods are long, colourless or pale yellow (up to 0.18 mm in length and 0.02 mm in width). The coenenchymal sclerites are very ornamented, and are mostly large spindles (up to 0.22 mm in length, and 0.06 mm in width) with up to 8 complete whorls of tubercles, and warty ends. They are red­orange to pale yellow and bicoloured, and together with P. s e n t a, include the longest spindles found in the genus. Capstans are less abundant in the slide samples; they are scarcely ornate, with only short tubercles.

Holotype. The holotype ( Fig. 1 G) is a single fan, 100 mm in height and 135 mm in width. Part of the holdfast was left behind when the specimen was collected. The preserved colony is reddish brown colony. Mesh branches are thick, about 2 mm in diameter. Numerous free twigs radiate from the fan as free branchlets. End­branchlets reach 12 mm. Coenenchymal sclerites are red­orange, pale yellow and bicoloured. They are mostly large spindles (up to 0.18 mm in length, and 0.06 mm in width) with 4–8 complete whorls of delicately sculpted tubercles, and with elongated warty ends, blunt, or acute ( Fig. 5 A). There are also small, pale yellow capstans (up to 0.05 mm in length and 0.03 mm in width), and larger ones (up to 0.08 mm in length by 0.04 mm in width) with short, moderately warty tubercles ( Fig. 5 B). Anthocodial sclerites are pale yellow. They are thin, long rods (up to 0.17 mm in length and 0.02 mm in width) with dentate margins and have acute, small warts, concentrated at the ends ( Fig. 5 C).

Remarks. This species is very similar to P. s e n t a, however, P. senta attains a larger size, the mesh branches are thinner, the meshwork finer (up to 23 mm long), and the colony has a more delicate appearance in comparison to the more robust P. sculpta . Dry specimens of P. s e n t a are brittle and the sclerites fall off easily, which is not the case in dry specimens of P. sculpta . Sclerites in both species are the largest recorded for the genus. Spindles in P. s e n t a and in P. sculpta reach the same size (up to 0.22 mm in length, and 0.06 mm in width), however, in P. s e n t a, the spindles have more whorls of tubercles (up to 10) than in P. sculpta (up to 8); thus sclerites of the latter have larger spaces between the whorls (and very warty tubercles). Capstans of both species are of similar shapes, but smaller sizes are reported for P. s e n t a (up to 0.06 mm in length) ( Breedy & Guzman 2003b). The colour of coenenchymal sclerites is definitely different. In all of the specimens of P. sculpta examined, two layers of differently coloured sclerites are clearly defined: reddish­orange sclerites in the inner coenenchyme and pale yellow on the surface. In P. s e n t a, on the other hand, all sclerites are of the same colour; brownish pink to colourless. Anthocodial rods are also different, being shorter (up to 0.14 mm in length) and less spiny in P. s e n t a. We have found P. s c u l p t a at several localities in the Gulf of Chiriquí, and also from two sites in the Gulf of Panama, down to 30 m in depth.

Breedy & Guzman (2003b) pointed out that Stiasny (1943) dealt with a species from Isla del Rey, Gulf of Panama, sent to him by Hickson, which agrees with P. senta . Therefore, it was expected that P. s e n t a would be found to occur in Panama. Pacifigorgia senta has been collected from deeper waters, down to 40 m in Costa Rica. In recent collections made by dredging 35–60 m in depth, in Panamá, specimens of P. senta were indeed found, thus the occurrence of P. s e n t a is herein reported and confirmed. Curiously, both P. senta and P. sculpta , were collected together in the same dredge, what indicates that they may occur together.

Habitat. Found from 10–40 m in depth, on vertical basaltic walls, living together with large P. e x i m i a colonies and many other octocorals. Though abundant in some places, this species is never the dominant species.

Etymology. An adjective (L), sculptus = carved, in allusion to the ornamentation of the spindles.

Distribution. Found widely distributed along Gulf of Panama, Gulf of Chiriquí, and Península de Azuero.

Figures

FIGURE 5. Pacifigorgia sculpta, new species (UCR 1497); SEM­micrographs of the sclerites: A – C, from the coenenchyme; C, from the anthocodia.

FIGURE 1. A – B, Pacifigorgia catedralensis, new species (UCR 1514) (preserved specimen); C – D, Pacifigorgia ferruginea, new species (STRI 423) (dry specimen); E – F, Pacifigorgia smithsoniana, new species (UCR 1406) (dry specimen); G – H, Pacifigorgia sculpta, new species (UCR 1497) (preserved specimen).