Linckia guildingi Gray, 1840

Cunha, Rosana, Martins, Luciana, Menegola, Carla & Souto, Camilla, 2021, Taxonomy of the sea stars (Echinodermata: Asteroidea) from Bahia State, including ontogenetic variation and an illustrated key to the Brazilian species, Zootaxa 4955 (1), pp. 1-78 : 42-45

Linckia guildingi Gray, 1840

Figures 22–23

Linckia guildingii Gray, 1840: 285 .

Linckia guildingii — Müller & Troschel 1842: 33; Rathbun 1879: 148; Clark 1938: 133; Tommasi 1958: 17; Brito 1962: 3; 1968: 4–5, pl. 1, fig. 3; 1971: 262; Lima-Verde 1969: 11; Tommasi 1970: 9, pl. 9, fig. 27; Tommasi & Aron 1988: 3; Tommasi et al. 1988: 6; Fernandes et al. 2002: 422; Gondim et al. 2008: 154; Carmo et al. 2015; Sandino et al. 2017: S294; Gurjão & Lotufo 2018: 11; Miranda 2018: 14; Patrizzi & Dobrovolski 2018: 182.

Linckia guildingi — Clark & Downey 1992: 275, pl. 67, fig. 42; Hendler et al. 1995: 76, figs. 20–21; Pérez-Ruzafa et al. 1999: 47; Williams 2000; Entrambasaguas 2003: 101–106; Entrambasaguas, 2008: 63–64; Benavides-Serrato et al. 2011: 174; Miranda et al. 2012: 144; Gondim et al. 2014: 32 , figs. 10a–e, 12d; Alvarado et al. 2017: S276; Souto & Martins 2017: 304–305, fig. 1D; Rubio-Polania et al. 2018: 190; Borrero-Peìrez et al. 2019: 5; Cunha et al. 2020: 38 , fig. 5; Prata et al. 2020.

Material examined (34 specs, 6–120 mm R). BRAZIL. Bahia (12°45’– 13°54’S; 38°37’– 38°58’W)— Salvador: Amaralina beach, intertidal, 8.iv.2008, 1 spec, R 6 mm ( UFBA 627 ); Pituba beach, intertidal, 26.i.2006, 1 spec, R 45 mm ( UFBA 169 ); intertidal, 4.xi.2010, 1 spec, R 57 mm ( UFBA 1213 ); intertidal, 2.v.2011, 4 specs, R 50–74 mm ( UFBA 1360 ); Itaparica Island , intertidal, 23.xi.1991, 2 specs, R 30–60 mm ( UFBA 194 ); Ponta de Humaitá beach, intertidal, ii.2011, 2 specs, R 45–54 mm ( UFBA 1269–1270 ). Barra Grande beach, Vera Cruz , 16 m, 2.x.2007, 1 spec, R 10 mm ( UFBA 529 ). Frades Island, Ponta de Nossa Senhora , 3 m, 17.x.2008, 8 specs, R 76–104 mm ( UFBA 674 ). Salvador: Farol da Barra beach, 17.i.2007, 1 spec, R 76 mm ( UFBA 470 ); Itapuã beach, intertidal, 1.viii.2007, 1 spec, R 114 mm ( UFBA 590 ); Pituba beach, intertidal, 16.iv.1991, 1 spec, R 95 mm ( UFBA 591 ); intertidal, 5.vii.1997, 2 specs, R 105–120 mm ( UFBA 41 ); intertidal, 2005, 1 spec, R 118 mm ( UFBA 639 ); intertidal, 8.iv.2008, 1 spec, R 87 mm ( UFBA 626 ); intertidal, 2.v.2011, 5 specs, R 82–113 mm ( UFBA 1360 ); Ponta de Humaitá beach, intertidal, xii.2010, 1 spec, R 116 mm ( UFBA 1268 ) .

Comparative material. BRAZIL. Alagoas, Ipioca coral reef , 1.vii.2007, 1 spec, R 35 mm ( UFBA 533 ) . WEST INDIES, 1 spec, R 24 mm ( NHM-UK 1953.4 .27.68, lectotype) ; 1 spec, R 15 mm ( NHM-UK 1953.4 .27.68, paralectotype) .

Description (R 76–120 mm). Small disc; average R/r 12.5. Five to six (rarely 1, 4 or 7) long, narrow, cylindri- cal arms ( Fig. 22A–B ). Abactinal surface with small, irregularly arranged, tumid plates covered by granules ( Fig. 22C ). Marginal plates larger than abactinal plates, tumid, covered by granules and arranged into two longitudinal rows. Papular areas large, only on abactinal surface, with 11–25 pores; number of pores lower near disc; actinal surface without papular areas. One to two madreporites ( Fig. 22E ) with deep furrows; only one per interradius.Anus inconspicuous. Terminal plates small, oval, covered by granules. Actinal plates ( Fig. 22D ) arranged into three rows extending almost or completely to tip of arm, covered by granules slightly larger than those on abactinal surface; plates near furrow larger than others. Two blunt adambulacral spines, proximal spine larger. Two rows of large, blunt subambulacral spines; outer spines granular-shaped. Innermost two spines on oral plates smaller than adjacent spines ( Fig. 22F ). Tube feet in two rows; sucking disc with perforated plates ( Fig. 23G–H ). Pedicellariae absent.

Ontogenetic variation (R 6–74 mm). Average R/r 9.2. Terminal plates proportionally larger than that of large specimen; plate naked or only with a few granules ( Fig. 23D ). Papular areas small, with 1–5 pores. Madreporite proportionally smaller than that of large specimen, with few gyres ( Fig. 23C ). Marginal plates prominent in specimens up to R 15 mm. Second row of subambulacral spines in specimens up to R 55 mm almost same size as adjacent granules ( Fig. 23E ), making it hard to differentiate them. Innermost spines on oral plate prominent ( Fig. 23F ).

Coloration. Specimens in vivo are whitish, pink or light brown; papular areas darker. Specimens in ethanol are beige to brown or light pink.

Distribution. Circumtropical ( Clark & Downey 1992; Alvarado & Solis-Marin 2013; Gondim et al. 2014; Cunha et al. 2020). BRAZIL: Pará, Paraíba, Pernambuco, Alagoas, Bahia, Espírito Santo, Trindade Island, Rio de Janeiro and São Paulo ( Verrill 1868; Rathbun 1879; Verrill 1915; Brito 1960, 1968; Tommasi 1970; Tommasi & Aron 1988; Gondim et al. 2014; Carmo et al. 2015; Souto & Martins 2017; Miranda 2018; Cunha et al. 2020).

Depth. 0–298 m ( Clark & Downey 1992).

Biological notes. Linckia guildingi is a nocturnal species, commonly found under rocks, in rock crevices, on coral reefs, rhodolith beds and in sandy bottoms from Bahia ( Alves & Cerqueira 2000; Sampaio 2010; Prata et al. 2020; present paper). Specimens in the Northern Brazil have also been found in muddy bottoms ( Miranda 2018). Juveniles of this species reproduce asexually by fission ( Clark 1933) and are often found with arms of different sizes (note that our measurements were based on the largest arm).

Martins et al. (2012) reported the commercial exploitation of this species for the aquarium trade, but the harvesting of L. guildingi in Brazil is currently prohibited ( Gurjão & Lotufo 2018). This species is classified as “Vulnerable” (baseline data indicates that the population size is small [i.e., number of mature individuals per subpopulation is 1000 or less] and currently in decline) by the Ministry of the Environment ( MMA 2018). Patrizzi & Dobrovolski (2018) predicted that the habitable range of L. guildingi may have a 10–28-fold expansion under higher atmospheric CO 2 concentrations. The effect of this expansion on the local communities is unknown, but it is likely to cause negative trophic impact ( Kordas et al. 2011).

Lectotype. NHM-UK 1953.4 .27.68.

Type locality. West Indies.

Remarks. The data presented by Clark & Downey (1992) and the morphology of the type specimens (R 15–24 mm) support the ontogenetic variation described here. According to H.L. Clark (1933), adult individuals vary from R 75–215 mm.

Linckia bouvieri and L. nodosa differ from L. guildingi by having smaller papular areas, secondary plates between the primary plates, and large abactinal plates (vs. large papular areas, secondary plates absent, and small abactinal plates). Also, the abactinal plates in L. bouvieri are flat (vs. tumid).

Genus Narcissia Gray, 1840

Type species. Narcissia canariensis ( d’Orbigny, 1839) (type by monotypy).

Remarks. The genus Narcissia is composed of four species: Narcissia ahearnae Pawson, 2007 (from NW Atlantic), Narcissia canariensis ( d’Orbigny, 1839) (from East Atlantic), Narcissia gracilis Clark, 1916 (from East Pacific) and Narcissia trigonaria Sladen, 1889 (from West Atlantic).

The classification of Narcissia has been controversial since molecular data placed N. trigonaria in an unusual phylogenetic position, sister to a clade with goniasterid and ophidiasterid species ( Mah & Foltz 2011). Here, we follow Mah (2020a) and keep Narcissia in the family Ophidiasteridae .

Figures

FIGURE 22. Linckia guildingi Gray, 1840. (A–B) Specimen in situ (not collected; photo credit: Cláudio Sampaio). Specimen (R 114 mm) (UFBA 590): (C) abactinal plates of arm, interspersed by large papular areas; (D) actinal view of arm; (E) abactinal region of disc with two madreporites on the right; (F) oral region. Scale bars: C–F, 10 mm.

FIGURE 23. Specimen (R 50 mm) of Linckia guildingi (UFBA 1360): (A) abactinal and (B) actinal view of body; (C) madreporite; (D) terminal region of the arm with ocular plate; (E) ambulacral furrow; (F) oral region; (G–H) perforated plates from tube feet. Scale bars: A–B, 20 mm; C, 1 mm; D, 10 mm; E–F, 2 mm; G–H, 100 μm.