Astropecten brasiliensis Mueller & Troschel, 1842

Gondim, Anne Isabelley, Christoffersen, Martin Lindsey & Pereira Dias, Thelma Lucia, 2014, Taxonomic guide and historical review of starfishes in northeastern Brazil (Echinodermata, Asteroidea), ZooKeys 449, pp. 1-56 : 7-8

Astropecten brasiliensis Mueller & Troschel, 1842

Astropecten brasiliensis Müller & Troschel, 1842: 68. Tommasi et al. 1988: 5. Manso 1989: 357. Fernandes et al. 2002: 422. Netto 2006: 25-26, pl. 2a, fig. 16a. Ventura et al. 2007: 230. Machado et al. 2008: 350. Lima and Fernandes 2009: 58. Xavier 2010: 75. Miranda et al. 2012: 143, 144.

Astropecten braziliensis Rathbun, 1879: 150. Tommasi 1970: 6.

Astropecten brasiliensis riensis Döderlein, 1917: 84.

Astropecten brasiliensis armatus Jonh, 1948: 503.

Astropecten armatus brasiliensis Tortonese, 1956: 329. Tommasi 1958: 12-13, pl. 2, fig. 3; 1970: 7, fig. 19. Brito 1962: 3; 1968: 7-8, pl. 4, fig. 3. Lima-Verde 1969: 10. Carrera-Rodrigues and Tommasi 1977: 81-83. Magalhães et al. 2005: 63.

Astropecten brasiliensis brasiliensis Döderlein, 1917: 83.

Astropecten armatus riensis Tommasi, 1958: 13-14, pr. 2, fig. 4. Brito 1962: 3; 1968: 8, pl. 4, fig. 2.

Astropecten riensis Tommasi, 1970: 7. Carrera-Rodrigues and Tommasi 1977: 89. Tommasi and Aron 1988: 3. Tommasi et al. 1988: 5.

Material examined.

Ceará: Fortaleza, Mucuripe, 1 spec., MNRJ285, 1945. Rio Grande do Norte: Areia Branca, Ponta do Mel, 1 spec., UFPB/ECH.1919, 23.VI.182. Bahia: Salvador, 2 spec., UFBA00132, 01.III.2000.

Type locality.

São Sebastião Island, São Paulo, Brazil ( Clark and Downey 1992).

Description.

Disk small with long, slender, dorsally flattened arms (~12.44 mm). Abactinal surface densely covered by overlapping and irregularly arranged paxillae. Paxillae with 26-30 long, blunt spinelets, the central ones sometimes shorter and more rounded than the marginal ones. Carinal paxillae larger than the adradial ones. Superomarginal figs longer (~5.7 mm) than wide (~1.19 mm), covered by short, apically rounded spinelets (giving them a granulose aspect), and having two large spines (rarely one). Inferomarginal figs with two long and flattened spines positioned vertically and forming a marginal fringe, the most ventral one being larger than the dorsal one. Adambulacral figs with three ambulacral spines, the inner one being slightly longer than the other two. Without pedicellariae.

Colour. According to Bernasconi (1957), live animals have an intense violet colour with the spines of the marginal fringe yellowish or pinkish. Actinal surface light salmon colour. When dry specimens may be light pink or whitish.

Distribution.

Honduras, Panama, Suriname, Brazil, Uruguay, and Argentina (Mar del Plata) ( Tommasi 1958, 1970, Clark and Downey 1992, Alvarado et al. 2008, Ventura et al. 2007). In Brazil: CE, PE, AL, BA, RJ, SP, SC, and RS, incluing the islands of Fernando de Noronha and Trindade ( Rathbun 1879, Verrill 1915, Tommasi 1958, 1970, Walenkamp 1976, Brito 1962, Lima-Verde 1969, Fernandes et al. 2002, Miranda et al. 2012). In this paper we establish the first record for Rio Grande do Norte. From 7 to 45 m in depth ( Ventura et al. 2007).

Remarks.

This species differs from the remaining species of the genus known from the Brazilian coast for presenting paxillary spinelets and spines of the marginal fringe long and thin and for having up to two spines on the supermarginal figs. The vast synonymy presented by Astropecten brasiliensis evidences the plasticity of some of its characters, such as the number of spines on the superomarginal figs. This character, together with the shape of the marginal spines and paxillae spinelets formed the basis for the establishment of the five known subspecies. Döderlein (1917) considered Astropecten armatus Gray, 1840 and Astropecten erinaceus Gray, 1840 subspecies of Astropecten brasiliensis on the basis of differences in the adambulacral and superomarginal spines. Boone (1933), Clark (1940) and John (1948) disagreed with Döderlein (1917) and considered the three species not to be different, stating that the characters proposed to diagnose the species were not significant. Walenkamp (1976) listed a series of variations observed in specimens from Surinam and established Astropecten brasiliensis and Astropecten riensis as distinct species. Bernasconi (1957), Brito (1968) and Tommasi (1958, 1970) adopted the subspecies proposed by Müller and Troschel (1842) and Döderlein (1917) for Brazilian material. Clark and Downey (1992), analysing the neotype of the species, concluded that Astropecten brasiliensis and Astropecten armatus are distinct, while Astropecten riensis is a synonym of the first. Furthermore, he considered all the described subspecies to be synonyms. We agree with the proposal of Clark and Downey (1992) and include the subspecies ( Astropecten brasiliensis riensis , Astropecten brasiliensis armatus , Astropecten brasiliensis brasiliensis and Astropecten armatus riensis ) and Astropecten riensis as synonyms of Astropecten brasiliensis . The specimen examined in this study was broken, but its taxonomic characters were observable, except for the loss of the superomarginal spines. Scars of these spines remained on the figs, however, and we were able to establish that two spines occurred per fig, characterizing an adult individual.

Ecological notes.

As a rule burrowed in sand substrates, where it is a generalist predator, feeding on a variety of organisms from the benthic endofauna, such as bivalves, gastropods, crustaceans, echinoderms, and polychaetes ( Ventura et al. 2007). As all species inhabiting soft sediments, Astropecten brasiliensis is suffering the impact of excessive collecting, being captured in bottom trawling nets and frequently do not resist the damage inflicted by these fishing efforts ( Machado et al. 2008). Presently the species is considered to be vulnerable to extinction along the Brazilian coast.