Muricea fruticosa group

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 : 8-11

Taxon classification Animalia Alcyonacea Plexauridae

Muricea fruticosa group Figures 1, 2, 3, 4

Muricea fruticosa Verrill, 1869.

Muricea fruticosa Verrill, 1869: 428; Kükenthal 1919: 752; Kükenthal 1924: 142; Harden 1979: 147; Hardee and Wicksten 1996: 129.

Muricea fruticosa typica Kükenthal 1924: 142; Harden 1979: 147.

Muricea fruticosa var. miser Verrill, 1869: 430; Kükenthal 1919: 752; Kükenthal 1924: 143; Harden 1979: 149 (syn. n.).

Thesea crosslandi Hickson, 1928: 354-356 (syn. n.).

Pseudothesea crosslandi (Hickson, 1928); Stiasny 1943: 64-66 (syn. n.).

Material.

Lectotype (here designated). YPM 1574c, dry, Pearl Islands, Panamá, 11-14 m, F.H. Bradley, 1866. (YPM 1792, fragment from lectotype, Verrill’s 1868 figured specimen). Paralectotypes. PANAMÁ: MCZ 706 (fragment from YPM 1574); MCZ 7020; USNM 33588; YPM 1566 (as Muricea fruticosa var. miser ), dry, Pearl Islands, F.H. Bradley, 1866, no more data; YPM 1660; YPM 1574a-b, d-e, same data as the lectotype; YPM 3067, dry, with the holotype of Muricea retusa at the base, Pearl Islands, 11-14 m, F.H. Bradley, 1866.

MCZ 5002; YPM 1566a-d; ZMUC-ANT 193 (as Muricea fruticosa var. miser ), dry, Pearl Islands, F.H. Bradley, 1866. MCZ 4126 ( Parisis fruticosa ), ZMUC-ANT 169 (as Thesea crosslandi ), ethanol preserved, San Jose Island, Pearl Islands, 49.3 m, T. Mortensen, 27 January 1916.

Description.

The lectotype is a large, bushy colony 35 cm tall, and about 45 cm wide. Four main branches, 25-35 mm in diameter, somewhat flattened, arise from an irregular, 52 mm diameter holdfast. The holdfast is spreading and raised about 30 mm above substrate, the specimen is attached to a plaster base for a past years museum display (Fig. 1A). The main branches subdivide very close to the base in secondary branches that immediately divide and subdivide in an irregular manner producing branches and branchlets closely placed, no more than 20 mm apart, at angles 45°-90°. Secondary branches and branchlets are 3-5 mm in diameter, mostly crooked and curved upwards or downwards. Some anastomosis occurs at the ends of branchlets. Unbranched terminal ends are 3-5 mm in diameter and 15-40 mm long. The axis is clear amber at the tips and darker at the base. The calyces are close together, or few millimetres apart, not imbricate, spreading outward and upward. They have large, strong, sharp sclerites forming the shelf-like projecting platform, 1-1.2 mm long, on the lower side (Fig. 1B). Polyps are on the upper side of the prominent calyces. The calyx sclerites give a prickly appearance to the colony (Fig. 1 A–B). The calyx size and spacing vary from the larger branches to the thinner, being larger and acute, and closer placed at the branchlets and shorter, blunt, and distant at the main branches. The polyp apertures are covered by anthocodial sclerites. The coenenchyme is thin, composed of reddish-brown, amber, pale yellow to whitish sclerites (Fig. 1 C–D). The outer coenenchyme and the calycular sclerites are composed of large, conspicuous unilateral spinous spindles visible to the naked eye (Fig. 2 A–B). These spindles are of diverse shapes, with blunt or acute ends, or irregular with one acute end and the other blunt, with bifurcated ends or with spiny tips. The unilateral spinous spindles are basically spinulose on the outer surface and tuberculate on the inner surface in this species, some tubercles are large, sharp and spiny. The spindles are deep reddish brown, brownish yellow to pale yellow, and combinations of them (Fig. 1C). These spindles are 0.53-2.1 mm long, and 0.11-0.55 mm wide (Fig. 2 A–B); they are forming the calyces and lying between them. The spindles bordering the calyx are long with stout, terminal spikes, 0.32-1 mm long and 0.07-0.2 mm wide, some with bifurcated warty ends (Fig. 2B). The axial sheath is composed of small, pale yellow to colourless spindles, 0.30-1 mm long and 0.05-0.12 mm wide, with whorls of small warts, and long spindles (Fig. 2 C–D). Anthocodial sclerites are of a yellow to a very pale yellow colour, arranged in irregular points, mostly composed of warty spindles, 0.40-0.64 mm long, and 0.07-0.1 mm wide, small warty rods 0.2-0.38 mm long and 0.5-0.1 mm wide, and small branched spindles around 0.20 mm long, and 0.15 mm wide (Fig. 2E).

The colony is bicoloured, reddish brown at the tips, fading to a light yellow towards the base (Fig. 1 A–B).

Habitat and variability.

There are two colour patterns in the syntype series, a marked bicoloured pattern, with dark reddish tips and whitish to pale yellow stems (Fig. 3 C–D), and intermediate patterns less differentiated (Fig. 3B). The bicoloured pattern is more evident in small specimens than in large colonies (Figs 1A, 3A), and in some case there is a dominance of white colour in the branches. In large colonies, we have observed both patterns in different branches in the same colony (Fig. 3A, arrows). The lectotype (YPM 1574c) is the largest specimen and with the most profuse branching, some other colonies in the syntypes are formed by just a few branches. Our recent collected material shows the bicolour pattern and the colonies can reach up to 25 mm long and 30 mm wide. They are mostly bushy, openly ramified colonies with white polyps. Some specimens change colour after drying, the white part becomes a rusty reddish. When preserved in alcohol they keep the colours unaltered and do not tint the spirit. The sclerites of the paralectotypes and the other material analysed are in the variation range of the species. The calyces can be more sparsely set and shorter in some colonies. The species is found on rocky substrata in clusters or solitary, attached to small debris or shells, especially when sparsely distributed. The colonies are in caves or exposed to the currents. They are found in clear or turbid waters. Muricea fruticosa is found at various localities in the Galápagos Islands, exposed to moderate currents and in caves, reaching no more than 15 cm wide (Fig. 4A) ( Hickman 2008, Breedy et al. 2009). The deepest record for the species is down to 102 m at Cocos Island seamounts (Fig. 4B), but it is found shallower in other places from 8 to 25 m deep.

Distribution.

From México to Perú. Type locality, Pearl Islands, Panamá.

Remarks.

Verrill (1869) described Muricea fruticosa with a collection of specimens from Panamá, and Muricea fruticosa var. miser based on some small specimens from the same locality but from shallower waters. He pointed out that the differences between the species and the variety are the small size of the colonies and the marked bicolour pattern. He also noticed that the calyces at the base of the branches were shorter, and that the sclerites were similar to the typical form but smaller. However, the reduction of the calyx size at the base of the branches occurs in most species of the genus, and the size of sclerites is in the range of variation found in the examined specimens. Hickson (1928) described Thesea crosslandi with specimens from Taboga Island, and San José Island (Pearl Islands), Panamá. Later, Stiasny (1943) re-examined Hickson specimens acknowledging the differences with the genus Thesea Duchassaing & Michelotti, 1864, and assigned the genus Pseudothesea Kükenthal, 1919 to the specimen. However, the description and the sclerite illustrations given by Hickson (1928), and Stiasny (1943) clearly refer to Muricea fruticosa , and we corroborated this after examination of Hickson’s specimens in the BM. For this reason, Thesea crosslandi and Pseudothesea crosslandi are herein treated as synonyms of Muricea fruticosa .

In order to establish the identity of this species, the YPM 1574c specimen is herein designated as the lectotype of Muricea fruticosa .

Other material revised.

COSTA RICA: UCR 482, 486, dry, Punta Conejo, Herradura, Puntarenas, 10 m, J. Cortés, 21 September 1996; UCR 520 (3), dry, Nicoya Gulf, CJ Kalb, 2 March 1967; UCR 576, dry, San Juanillo, Guanacaste, 12.5 m, J. Cortés, 14 June 1991; UCR 588, dry, Pitahaya Beach, Guanacaste, 20-23 m, J. Cortés, 15 June 1991; UCR 837-839, dry, Ballena Bay, Nicoya Gulf, 40 m, R/V Victor Hensen, 2 December 1993. ECUADOR: CASIZ 105032, ethanol preserved, Santa Cruz Island, Nameless Islet, Galápagos Islands, 20 m, P. Humann, no collection date. CDRS 03-76, ethanol preserved, Los Hermanos, Galápagos Islands, 9 m, C. Hickman, 17 January 2003. CDRS 06-33, ethanol preserved, Nameless Island, Galápagos Islands, 9-10 m, C. Hickman, 25 May 2006. IIN 7, 9, dry, Tambip, Salinas, 12-14 m, F. Rivera, P. Martínez, 20 July 2010; IIN 21, dry, Bajo Lunes, Salinas, 18 m, F. Rivera, P. Martínez, 21 July 2010; IIN 34, 69, Gigima, Salinas, 12-14 m, F. Rivera, P. Martínez, 22 July 2010; IIN 88, 89, 123, dry, Los Ahorcados, Machalilla National Park, 10-12 m, F. Rivera, P. Martínez, 25 July 2010. EL SALVADOR: UCR 1938, ethanol preserved, Departamento la Libertad, Playa Mizata, J. Segovia, 27 February 2010. MÉXICO: CASIZ 097734, ethanol preserved, Roca Partida, South side, Revillagigedo Islands, 36 m, R.J. Van Syoc, M/V "Royal Star, Clipperton Island Expedition 1994, 2 May 1994. CASIZ 103387, ethanol preserved, Boca del Tule to Arena Blanca, Baja California Sur, 30 m, W. Lee, J. Moran, J. McCosker, 26-27 April 1976; CASIZ 100843, ethanol preserved, Roca Alejos, Baja California Sur, 18-33, Robert Van Syoc, Cordell Expeditions, 5 November 1990. STRI 1124, 1130B, 1151, ethanol preserved, La Blanca, Oaxaca, 46-48 m, R. Abeytia, 23 August 2004. PANAMÁ: STRI 405, Seca Grande Island, 20 m, H. Guzman, 26 August 2002; STRI 534, Bajo Bolano, 25 m, H. Guzman, 16 April 2003; STRI 572, ethanol preserved, Viudas Island, 10-20 m, H. Guzman, 18 April 2003; STRI 836, San Telmo Island, 27 m, H. Guzman, 7 April 2004; STRI 848, Sur Pacheca, 2 m, H. Guzman, 20 April 2004; STRI 865, Achotines, 3-10 m, H. Guzman, 5 May 2004; STRI 879, Pearl Island, H. Guzman; STRI 888, Pearl Island, 25 m, H. Guzman, 15 August 2004; STRI 892, Pearl Island, H. Guzman, 15 August 2004; STRI 942, Pearl Island, 3-20 m, H. Guzman, 23 September 2004. USNM 34063, dry, Gulf of Panamá, L.C. Cash, no more data. PERÚ: CZA 230, dry, Foca Island, 12-15m, Y. Hooker, 14 June 2009; CZA 255; 293, dry, Punta Sal, 12-15m, Y. Hooker, 2 July 2011.