Linckia guildingi Gray, 1840

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 : 38-40

Linckia guildingi Gray, 1840

Figure 5

Linckia guildingii Gray, 1840: 285 [type locality: San Vicente, Caribbean Sea, viz. Clark & Downey, 1992]; Hendler et al., 1995: 76, figs. 20–21; Benavides-Serrato et al., 2011: 174; Fernandes et al. 2002: 422; Gondim et al. 2008: 154.

Linckia guildingi – Pérez-Ruzafa et al. 1999: 47 ; Williams, 2000; Entrambasaguas, 2008: 63; Miranda et al. 2012: 144; Gondim et al. 2014: 32 , figs. 10a–e, 12d.

Trindade and Martin Vaz specimens. Brazil, Espírito Santo, Trindade Island , Enseada das Orelhas , 20°29’40.2”S, 29°20’32.9”W, 6.vii.2013, 14 m: 1 spm R=83, r=10 ( MZUSP 1591 ) ; 18.iv.2014, 12.1 m: 1 spm R=127, r=13 ( MZUSP 1604 ) ; 15.vi.2012, 9.7 m: 1 spm R=100, r=12 ( MZUSP 1608 ) . Praia das Cabritas , 20°29’41”S, 29°19’39”W, 5.xi.2014, 13.7 m: 1 spm R=93, r=11 ( MZUSP 1590 ) . Ponta Noroeste, 20°29’46.4”S, 29°20’35.4”W, 9.vii.2012, 17.7 m: 1 spm R=170, r=13 ( MZUSP 1594 ) . Praia da Calheta , 20°30’26”S, 29°18’44”W, 24.vi.2012, 4 m: 4 spms, R=93, r=13; R=95, r=10; R=100, r=10; R=110, r=10 ( MZUSP 1593 ) ; 14.vii.2013, 4 m: 2 spms, R=70, r=9; R=113, r=12 ( MZUSP 1599 ) ; 26.vi.2012, 14.3 m: 1 spm, R=120, r=10 ( MZUSP 1606 ) ; 18.vi.2012, 12 m: 1 spm, R=100, r=8 ( MZUSP 1602 ) ; 10.iv.2014, 15 m: 1 spm, R=95, r=9 ( MZUSP 1605 ) ; 24.iv.2012, 4 m: 2 spms, R=77, r=8; R=97, r=8 ( MZUSP 1610 ) . Parcel das Tartarugas, 20°30’37.6”S, 29°18’28.1”W, 28.vi.2012, 0 m: 1 spm R=90, r=8 ( MZUSP 1592 ) . Enseada dos Portugueses, Farol, 20°30’52”S, 29°19’15”W, 17.iv.2014, 13.3 m: 1 spm R=97, r=9 ( MZUSP 1589 ) ; 15.vii.2013, 12 m: 1 spm R=83, r=10 ( MZUSP 1598 ) . Enseada dos Portugueses, 20°30’52.3”S, 29°19’15.6”W, 8.vii.2015, 11.6 m: 1 spm R=43, r=5 ( MZUSP 1585 ) ; 31.vii.2015, 0 m: 1 spm R=105, r=11 ( MZUSP 1586 ) ; 18.iv.2014, 10.2 m: 3 spms R=47, r=6; R=53, r=11; R=60, r=7 ( MZUSP 1588 ) ; 10.vii.2012, 14.6 m: 1 spm R=43, r=4 ( MZUSP 1613 ) . Enseada das Tartarugas, 20°30’56.7”S, 29°18’08.7”W, 5.vii.2013, 0 m: 5 spms, R=27, r=4; R=34, r=6; R=44, r=6; R=47, r=5; R=82, r=9 ( MZUSP 1583 ) ; 2.ii.2012, 15.2 m: 1 spm R=108, r=11 ( MZUSP 1595 ) ; 3.viii.2013, 12 m: 3 spms R=93, r=12; R=110, r=13; R=120, r=12 ( MZUSP 1597 ) ; 17.vii.2013, 9.9 m: 1 spm R=100, r=10 ( MZUSP 1601 ) ; 26.vi.2012, 9.5 m: 1 spm R=113, r=11 ( MZUSP 1607 ) . Praia das Tartarugas , 20°31’03.89”S, 29°18’08.4”W, 12.iv.2014, 0 m: 1 spm R=48, r=6 ( MZUSP 1587 ) . Enseada das Cachoeiras, Farrilhões, 20°31’22”S, 29°19’52”W, 9.vii.2013, 10.4 m: 1 spm R=165, r=13 ( MZUSP 1596 ) . Enseada do Lixo , 20°31’33.9”S, 29°19’33.6”W, 24.vi.2012, 23.5 m: 3 spms R=170, r=13; R=230, r=15; R=260, r=10 ( MZUSP 1603 ) . Martin Vaz Island , 20°30’45.7”S, 29°18’21.9”W, 24.vii.2013, 12.3 m: 1 spm R=90, r=14 ( MZUSP 1600 ) .

Comparative material. Brazil, Alagoas, Barra de Camaragibe , 9°20’19”S, 35°26’10”W, 29.x.2011: 1 spm R=57, r=6 ( MZUSP 1949 ) . Bahia, Boipeba Island, Praia de Tassimirim , 13°34.882’S, 38°54.821’W, 15.viii.2011: 2 spms R=55, r=7; R=46, r=4 ( MZUSP 1950 ) ; Praia de Bainema , 13°38.274’S, 38°53.546’W, 19.viii.2011: 2 spms R=90, r=8; R=95, r=8 ( MZUSP 1951 ) ; Porto Seguro, Ponta Grande , 16°22.641’S, 39°00.342’W, 16.xi.2010, 0.6 m: 6 spms, R=26, r=5; R=60, r=6; R=60, r=7; R=61, r=7; R=62, r=6; R=63, r=6 ( MZUSP 1952 ) . Rio de Janeiro, Angra dos Reis , Ponta do Bananal , 23°04’23”S, 44°09’49”W, 20.i.2000: 1 spm, R=88, r=11 ( MZUSP 1953 ) ; Ilha Grande, Grumixama , 23°05’16”S, 44°14’14”W, 23.vii.1966: 1 spm, R=62, r=8 ( MZUSP 1954 ) ; Jorge Grego Island , 23°13’06”S, 44°13’65”W, 9.viii.2009: 1 spm, R=110, r=11 ( MZUSP 1955 ) .

Distribution. Circumtropical ( Clark & Downey, 1992; Alvarado & Solis-Marin, 2013; Gondim et al. 2014). Brazil: Paraíba, Pernambuco, Alagoas, Bahia, Trindade and Martin Vaz Archipelago, Rio de Janeiro and São Paulo (Verril, 1868; Rathbun, 1879; Verril, 1915; Brito, 1960, 1968; Tommasi, 1970; Clark & Downey, 1992; Ventura et al., 2006; Gondim et al., 2014). Depth range: 0–298 m ( Clark & Downey, 1992).

Recognition characters. Small disk in relation to total body size. Five (4–6) long, narrow, cylindrical arms. Abactinal plates tumid, polygonal, tessellate, irregularly arranged in a reticulate pattern. Primary plates on abactinal surface without secondary plates between them. Many large papular areas between abactinal plates, with 18–30 pores per area. Lowermost papular area above inferomarginal plates. Two rows of subambulacral spines, innermost consisting of large, granuliform, more rounded spines; one subambulacral spine for each two ambulacral spines. Pedicellariae absent ( Clark & Rowe, 1971; Clark & Downey, 1992).

Color in life. Strongly variable. Adults have been reported to be reddish-brown, yellowish-brown, brownish or violet, whereas juveniles can be red, brown, violet or with purple spots ( Hendler et al. 1995). Clark & Downey (1992) referred to “usually mottled grey”. The Trindade were blue gray in color with scattered light spots ( Figure 5A ). H. L. Clark (1933) suggested that changes in color pattern in this species might be related to habitat, but recently, Entrambasaguas (2008) found no evidence of changes in color pattern induced by habitat in L. guildingi . Genetic differentiation has been found between blue and orange morphs of L. laevigata across the Indian and Pacific oceans ( Magsino et al. 2002). However, Williams (2000) recovered two clades within L. guildingi based on COI sequences, none of which referable to color or geographic distribution patterns.

Habitats. Commonly encountered on coral reefs ( Williams, 2000), this is the most frequently encountered species in Trindade, where it can be found on corals, algae or rocky bottoms, between the tide zone and 23.5 m ( Figure 5A ).

Comments. Nine species of Linckia are currently accepted, three of which have been recorded from the Atlantic Ocean: L. bouvieri Perrier, 1875 (EA); L. nodosa Perrier, 1875 (WA; also Saint Helena), and L. guildingi Gray, 1840 (CT, including Ascension). The specimens from Trindade and Martin Vaz are confidently assigned to L. guildingi on the basis of it having many large papular areas between the abactinal plates, primary plates on abactinal surface without secondary plates between them, and no large, raised hemispherical abactinal plates ( Fig. 5D ), whereas L. bouvieri and L. nodosa display smaller papular areas, secondary plates between the primary ones, and have large, raised hemispherical abactinal plates. A single specimen, confidently referred to L. guildingi by Pawson (1978), is known from Ascension. Although Downey (1973) considered L. nodosa [as L. bouvieri ] (R=134; R=144) the largest western Atlantic Ophidiasteridae , some Trindade specimens of L. guildingi are actually larger (R=165, MZUSP 1596; R=170, MZUSP 1594; MZUSP 1603; R=230 and R=260, MZUSP 1603).

Figures

FIGURE 5. Linckia guildingi Gray, 1840. A. Specimen from Trindade Island photographed in situ (MZUSP 2015). B–I. MZUSP 1595: B, C. Abactinal and actinal views. D. Abactinal plates and papulae. E. Detail of the madreporite. F. Mouth. G. Ambulacral spines. H. Actinal granules. I. Tip of the arm, abactinal view. J–Q. Scanning electron microscope (MZUSP 1591). J–L. Abactinal plates. M–O. Ambulacral plates. P, Q. Adambulacral plates. Scale bars: B–C, 20 mm; D–I, 1 mm; J–Q, 200 μm.