Copidaster lymani A. H. Clark, 1948

Cunha, Rosana, Tavares, Marcos & Jr, Joel Braga De Mendonça, 2020, Asteroidea (Echinodermata) from shallow-waters of the remote oceanic archipelago Trindade and Martin Vaz, southeastern Atlantic, with taxonomic and zoogeographical notes, Zootaxa 4742 (1), pp. 31-56 : 36-38

Copidaster lymani A. H. Clark, 1948

Figures 3 , 4A

Copidaster lymani A. H. Clark, 1948: 55 , pl. 2, figs. 1–2 [type locality: Key Largo, Florida, viz. Clark & Downey, 1992]; Hendler et al., 1995: 76, fig. 19; Fernádez, 2001: 134.

Trindade specimens. Brazil, Espírito Santo, Trindade Island , Enseada das Orelhas, 20°29’40.2”S, 29°20’32.9”W, 27.vii.2015, 10.5 m: 1 spm R=112, r=11 ( MZUSP 1547 ) ; 12.xi.2014, 6.9 m: 1 spm R=113, r=9 ( MZUSP 1548 ) ; 13.xi.2014, 14.4 m: 3 spms R=107, r=11; R=122, r=10; R=160, r=10 ( MZUSP 1550 ) ; 24.x.2014, 15.4 m: 1spm R=138, r-11 ( MZUSP 1551 ) . Ponta Noroeste, 20°29’46.4”S, 29°20’35.4”W, 7.iv.2012, 11.6 m: 1 spm R=124, r=9 ( MZUSP 1546 ) . Enseada do Lixo , 20°31’29.8”S, 29°19’43.9”W, 7.ii.2012, 25 m: 1 spm R=115, r=9 ( MZUSP 1549 ) .

Comparative material. Copidaster lymani A. H. Clark, 1948 : U.S.A., Gulf of Mexico, Florida, Dry Tortugas, 24°47’35.52”N, 83°52’50.27”W, 29.iv.1997, 95 m: 1 spm R=62, r=7 (UF–3372). Copidaster schismochilus (H.L. Clark, 1922) : Bermuda, Challenger Bank, 32°00’N, 65°00’W, 1.viii.1903, 56 m: holotype, R=98, r=10 ( MCZ AST–2758).

Distribution. U.S.A. (Florida), Mexico, Cuba, Belize, Panama, Brazil (Trindade Island, present study), Ascension Island ( Hendler et al., 1995; Fernádez, 2001; Alvarado & Solis-Marin, 2013). Depth range: 0–95 m ( Clark & Downey, 1992; present study).

Recognition characters. Five long, cylindrical arms, up to 10 times longer than length of disc, constricted at bases. Abactinal plates flattened, T-shaped, imbricated. Second, long, abactinal plate bar-like connecting anterior plates laterally. Skeleton covered with gelatinous membrane. Carinal and adradial series of plates connected to each other by single internal plate at proximal half of ray. Acute subambulacral spines very close to each other, not embedded in dense integument of body wall. Pedicellariae between ambulacral and subambulacral spines, abundant ( Miller, 1984; Clark & Downey, 1992; Solis-Marin & Laguarda-Figueras, 2010; Kogure & Kohtsuka, 2014; present study).

Color in life. Reddish tan or orange, with darker red mottling or banding, Figure 3A (see also Clark & Downey, 1992). Subambulacral spines and furrow spines white proximally and distally, orange medially. Pedicellariae and madreporite white, conspicuously contrasted by darker surrounding skin ( Miller, 1984). Yellowish cream in ethanol ( Figure 3B, C ).

Habitats. Copidaster lymani inhabits both hard (coral reefs, rock, rubbles, and calcareous algae) and softmixed bottoms (mud, sand) ( Miller, 1984; Fernádez, 2001; Alvarado & Solis-Marin, 2013). The specimens from Trindade were found sheltered in rocky and calcareous bottoms or among calcareous algae ( Figures 3A , 4A ) between 6.9 and 25 meters. In aquarium captivity, C. lymani concealed itself under rocks and remained motionless for long periods of time ( Fernádez, 2001). Miller (1984) reported the co-occurrence of C. lymani and Linckia guildingi Gray, 1840 (as Ophidiaster guildingi ), in the same area at Carrie Bow Cay ( Belize). Similarly, the two species co-occurred in Trindade.

Comments. Copidaster A. H. Clark, 1948 (sensu Miller, 1984, and Clark & Downey, 1992) consists of four species: C. cavernicola Solis-Marin & Laguarda-Figueras, 2010 (WA); C. japonicus Kogure & Kohtsuka, 2014 (NWP); C. lymani A. H. Clark, 1948 (WA), and C. schismochilus (H. L. Clark, 1922) (WA). The specimens from Trindade are confidently assigned to C. lymani . Copidaster lymani can be immediately separated from C. cavernicola in having pedicellariae between the ambulacral and subambulacral spines (whereas these areas are naked in C. cavernicola ). Clark & Downey (1992), while accepting both C. schismochilus and C. lymani as valid species, admitted that C. schismochilus might be “simply a large, possibly senescent, specimen of [C.] lymani ”. We concur with Clark & Downey’s (1992) observation that the number of papulae is higher in the holotype of C. schismochilus than in C. lymani . However, this characteristic should not be used to separate between the two species. In the Trindade specimens (R= 105–160) the number of papulae varies with the size of the specimen as well as with the papular region considered (see also Miller (1984)). Near the disc and in the distal region of the arm, the amount of papulae is always smaller (8–12) relative to the rest of the arm (18–32) ( Fig. 3D ). We agree with Miller (1984) that C. lymani actually stands apart from C. schismochilus in that its carinal and adradial series of plates ( Fig. 3I ) are connected to each other by a single internal plate ( Fig. 3J ) in the proximal half of the ray ( Fig. 3D ), whereas 2–3 dorsolateral plates connect the carinal and adradial series of plates in C. schismochilus . Copidaster lymani can be separated outright from C. japonicus in having acute subambulacral spines very close to each other, not embedded in the dense integument of the body wall ( Fig. 3G ) (versus clavate subambulacral spines apart from each other, embedded in body wall with only the thick tip protruding in C. japonicus ).

The presence of C. lymani in Trindade constitutes the first record of the species from the southwestern Atlantic.

Figures

FIGURE 3. Copidaster lymani A. H. Clark, 1948. A–N. MZUSP 1550: A. Specimen from Trindade Island photographed in situ. B, C. Abactinal and actinal views. D. Abactinal plates and papulae. E. Detail of the madreporite. F. Mouth. G. Ambulacral spines. H. Tip of the arm, abactinal view. I–N. Scanning electron microscope. I, J. Abactinal plates. K, L. Ambulacral plates. M, N. Valves of the abactinal pedicellariae. Scale bars: B–C, 20 mm; D–H, 2 mm; I, K–L, 400 μm; J, 200 μm; M–N, 40 μm.

FIGURE 4. A. Copidaster lymani A. H. Clark, 1948, Trindade Island, Enseada das Orelhas. B–D. Mithrodia clavigera (Lamarck, 1816). B, C. Trindade Island, Príncipe beach. D. Fernando de Noronha, tide pool at Boldró beach. Photograph by Gabriela C. Zeineddine. E. Oreaster reticulatus (Linnaeus, 1758), Trindade Island, Enseada dos Portugueses, Farol. F. Luidia alternata alternata (Say, 1825) Trindade Island, Ponta da Calheta.