Mellita aff. quinquiesperforata ( Leske, 1778 )

Gondim, Anne Isabelley, Moura, Rafael Bendayan De, Christoffersen, Martin Lindsey & Dias, Thelma Lúcia Pereira, 2018, Taxonomic guide and historical review of echinoids (Echinodermata: Echinoidea) from northeastern Brazil, Zootaxa 4529 (1), pp. 1-72 : 36-38

Mellita aff. quinquiesperforata ( Leske, 1778)

Figures 12 A–J, 18 F, 19 F, G

Echinodiscus quinquiesperforata Leske, 1778: 133 .

Scutella quinquefora Lamarck, 1816: 9 .

Mellita testudinata Klein, 1734: 422 –425.– Rathbun, 1879: 144.

Clypeaster pentaporus Gmelin, 1791: 3189 .

Mellita latiambulacra H.L. Clark, 1940a: 62 .

Mellita lata H.L. Clark, 1940a: 437 –439.

Mellita quinquiesperforata H.L. Clark, 1911: 599 .– Tommasi, 1957: 21, 31–32, fig. 3, pl. 2, figs 1–2, pl. 3, figs 3–4; 1974: 187.– Matos et al. 2000: 741 –745.– Fernandes et al., 2002: 422.– Ventura et al., 2007b: 279, tab.11.2, 281, fig. 11.2f, 290, anexo 11.1.– Gondim et al., 2008: 155; 2013b: 515.– Oliveira et al., 2010: 10, fig. 4g.– Xavier, 2010: 75.– Miranda et al., 2012: 142.

Mellita quinquiesperforata latiambulacra Mortensen, 1948a: 426 .– Bernasconi, 1955: 63 –64, pl. IV, figs 5, 6.– Tommasi, 1959: 602, 603; 1964: 87–90.– Brito, 1962: 6; 1968: 28, pl. 14, fig. 2–3.

Mellita quinquiesperforata tenuis H.L. Clark, 1940a: 442 –444, pl. 60, fig. 2, pl. 61, fig. 2.

Mellita (Mellita) quinquiesperforata Brito, 1960a: 6 –7, fig. 2a–c.– Tommasi, 1966a: 25.

Mellita (Mellita) quinquiesperforata var. latiambulacra Lima-Verde, 1969: 10 .

Material examined. Ceará: 3 spms, Ponta Grossa, Aracati, 24.VI.1982 [UFPB/ECH.1231]; 1 spm, Arpoeira Beach, Aracaraú, 07.VIII.1982 [UFPB/ECH.1232]. Rio Grande do Norte: 5 spms, Timbau Beach, 29.II.1980 [UFPB/ECH.1205]; 3 spms, Diogo Lopes, Macau, 11.XI.2007 [UFPB/ECH.1228]; 1 spm, Diogo Lopes, Macau, 12.XI.2007 [UFPB/ECH.1314]; 7 spms, Ponta Santo Cristo, to the east of São Miguel do Gostoso, 21.VI.1982 [UFPB/ECH.1894]; 1 spm, Ponta do Tubarão, criffs in front of Chico Martins, Macau, 02.II.2011 [UFPB/ ECH.1929]; 7 spms, river mouth of Rio Tubarão, Diogo Lopes, Macau, 15.XI.2009 [UFPB/ECH.1930]. Paraíba: 12 spms, Baía da Traição, Baía da Traição, 04.VI.1979 [UFPB/ECH.350]; 1 spm, Santa Catarina Beach, Cabedelo, 18.V.2007 [UFPB/ECH.616]; 13 spms, Baía da Traição, Baía da Traição, 24.XI.2007 [UFPB/ECH.1015]; 6 spms, Baía da Traição, 04.V.2008 [UFPB/ECH.1167]; 11 spms, Bessa Beach, João Pessoa, 18.II.1979 [UFPB/ ECH.1206]; 2 spms, Carapibus Beach, Conde, 21.III.2008 [UFPB/ECH.1207]; 3 spms, Carapibus Beach, Conde, 08.III.2008 [UFPB/ECH.1208]; 1 spm, Cabo Branco Beach, João Pessoa, 05. XII.1 983 [UFPB/ECH.1213]; 1 spm, Lucena Beach, Lucena, 07.X.2007 [UFPB/ECH.1227]; 21 spms, Cabo Branco Beach, João Pessoa, 18.VIII.1978 [UFPB/ECH.1229]; 2 spms, Lucena Beach, Lucena, 07.X.2007 [UFPB/ECH.1230]; 1 spm, Coqueirinho Beach, Conde, 03.VI.2008 [UFPB/ECH.1285]; 37 spms, Ponta de Campina, Cabedelo, 19.XI.1983 [UFPB/ECH.1292]; 1 spm, Bessa Beach, João Pessoa, 18.XII.2007 [UFPB/ECH.1293]; 2 spms, Costinha Beach, Lucena, 07.X.2007 [UFPB/ECH.1294]; 1 spm, Cabo Branco Beach, João Pessoa, 25.X.2007 [UFPB/ECH.1295]; 2 spms, Barra de Mamanguape Reefs, Rio Tinto, 10.I.2009 [UFPB/ECH.1458]; 2 spms, Maceiozinho Beach, Jacumã, Conde, 06.V.2008 [UFPB/ECH.1474]; 11 spms, Santa Catarina Beach, Cabedelo, 05.V.2009 [UFPB/ECH.1931]; 4 spms, Cabo Branco Beach, João Pessoa, 09.II.2001 [UFPB/ECH.1942]; 1 spm, Barra de Mamanguape, Rio Tinto, 13.I.2017 [UFPB/ECH.2287]. Alagoas: 1 spm, Pontal do Peba, Piaçabuçu, 27.I.1983 [UFPB/ECH.1233]; 8 spms, Japaratinga Beach, Japaratinga, 18.IX.2009 [UFPB/ECH.1892]. Sergipe: 1 spm, Mosqueiro Beach, Aracajú, 25. IV.2010 [UFPB/ECH.1920]; 1 spm, Sarney Beach, Aracajú, 30.VIII.1995 [UFSITAB-6]; 1 spm, Sarney Beach, Aracaju, 30.VII.1995 [UFSITAB-117]; 1 spm, Aruana Beach, Aracajú, 21.I.2007 [UFSITAB-120]. Bahia: 3 spms, Iemanjá Beach, Salvador, 10.I.2007 [UFSITAB-116].

Description. Test wider than long (TL = 71.7 mm; TW = 78.7 mm), with thin ambitus, domed anteriorly, highest point of test located slightly anterior to apical system and curving down abruptly to anterior margin ( Fig. 12A, C ). Apical system monobasal, with four gonopores ( Fig. 12I ). Petaloid large, corresponding to a little more than 50% TL ( Fig. 12A, C ). Posterior petals slightly longer than anterior ones ( Fig. 12A, C ). Five lunules, anal lunule longer than paired ambulacral lunules ( Fig. 12 A–D). Aboral primary spines short and club-shaped, covering the test uniformly ( Fig. 12A, H ). Each Miliary spines each with sac-like structure on tip, densely scattered among primary spines. Lunules with two types of spines: aboral ones longer, flat and enlarged at tip (similar to swim fins). Inner spines elongate and tapering. Oral surface flat, with long, thin locomotory spines that are slightly curved at the base, occupying the centre of interambulacra ( Fig. 12b, D ). Geniculate spines short and slightly curved, in fields from margins of interambulacra to margins of food grooves. Among these are long, slender spines in areas near pressure drainage channels ( Fig. 12B ). Peristome pentagonal and slightly anterior ( Fig. 12B, D ). Periproct oval to triangular, very close to peristome, deeply indenting basicoronal plate ( Fig. 12B, D ). Periproctal membrane covered by large plates of different sizes and shapes. Interambulacral basicoronal plates longer than ambulacral ones. Food grooves bifurcating at distal edges of ambulacral basicoronals and highly branched distally ( Fig. 12D ).

Pedicellariae. Pedicellariae scattered over entire test, being more abundant in oral interambulacra and in areas close to lunules, peristome, and periproct. Bidentate pedicellariae with a long neck (as long as or shorter than stalk) and short head. Valves short, with narrow and slightly curved, median region enlarged, margin slightly serrate, and a terminal tooth that crosses with the tooth of the opposing valve (this tooth is seen only in the larger pedicellariae) ( Fig. 12 E–G).

Colour. Greenish or brownish ( Fig. 12A, B , 19F ). Naked test white ( Fig. 12C, D ).

Distribution. In Brazil from MA, PI, CE, PB, PE, AL, SE, BA, ES, RJ, SP, SC, and RS ( Brito 1962; Tommasi 1964, 1966a, 1974; Lima-Verde 1969; Harold & Telford 1990; Fernandes et al. 2002; Magalhães et al. 2005; Martins & Martins de Queiroz 2006; Gondim et al. 2008; Lima & Fernandes 2009; Gondim & Giacometti 2010; Oliveira et al. 2010; Xavier 2010). In this study, we provide the first record of the species for the State of Rio Grande do Norte. From depths between 0 and 550 m, being more common between 1 and 3 m ( Tommasi 1974).

Remarks. Seven extant species of Mellita are known, of which only M. quinquiesperforata had been recorded for Brazil. The taxonomic history of this species is quite complex ( Harold & Telford 1990). Among several subspecies, M. quinquiesperforata latiambulacra was cited for Brazil on the basis of the diagnostic character, a more rounded test ( Tommasi 1964). Harold & Telford (1990) conducted a morphological analysis of the genus and established the following diagnostic characters for M. quinquiesperforata : sharply inclined anterior profile; position of maximum thickness usually distinctly anterior to centre; test very broad; unique spatulate spines bordering the lunules. Recently, Coppard et al. (2013) conducted a phylogeographic study of the genus Mellita along the coasts of the Americas and concluded that the specimens from Brazil (collected along the littoral of the State of Paraíba, northeast Brazil), represented a new species, yet unnamed and not described. According to these authors, the new species of Mellita is distributed from the Lesser Antilles to tropical Brazil. Herein we provisionally considered our specimens from the northeastern Brazil as M. aff. quinquesperforata, based on the results by Coppard et al. (2013), its morphological similarities with M. quinquiesperforata and recommenations of the ICZN (1999). We only examined adults, in which no significant morphological variations were observed. Mellita aff. quinquiesperforata has four gonopores. Tommasi (1966a) used this feature as a character to distinguish Encope (five gonopores) and Mellita . Tommasi (1957) examined a single specimen of Mellita with five gonopores, which he considered an anomaly.

Ecological notes. This species lives in sandy substrates. On beaches, it occurs mainly near the surf zone. Mellita aff. quinquiesperforata is the most common clypeasteroid along the northeastern coast of Brazil and may form dense populations just behind the surf zone ( Borzone 1992). In the present study, we observed high densities of this species in hypersaline estuaries, where it occurred together with Leodia sexiesperforata and Encope emarginata . Several specimens harboured one or two small crabs on the oral surface, possibly of the genus Dissodactylus Smith, 1870 . Along the semiarid littoral of the State of Rio Grande do Norte, M. aff. quinquiesperforata is one of the main preys of the gastropod Cassis tuberosa ( Mota 2012) .

Figures

FIGURE 12. Morphological characters of Mellita aff. quinquiesperforata (UFPB/ECH.1015). (A) Aboral view; (B) Oral view; (C) Aboral view of the naked test; (D) Oral view of naked test; (E) Bidentate pedicellariae; (F–G) Valve of bidentate pedicellariae; (H) Detail of spines from aboral surface; (I) Apical system; (J) Spines from ambitus.

FIGURE 19. Ecological aspects of some echinoids from northeastern Brazil. (A) Eucidaris tribuloides parasitized by eulimid gastropod (arrow); (B) Partial view of coastal reef eroded by Echinometra lucunter; (C) Lytechinus variegatus on coral reef exhibiting covering behaviour at night; (D) Dead specimen of Lytechinus variegatus recently preyed upon (arrow) by juvenile Cassis tuberosa; (E) Dissodactylus crab associated with oral surface of sand dollar Encope emarginata on sandy beach; (F) Diseased specimen of Mellita aff. quinquiesperforata; (G) Dead sand dollars (M. aff. quinquiesperforata) on sandy beach after disease outbreak.