Coronatum baiensis Martins & Souto, 2012

Prata, Jéssica, Manso, Cynthia Lara De Castro & Christoffersen, Martin Lindsey, 2020, Dendrochirotida (Echinodermata: Holothuroidea) from the northeastern coast of Brazil, Zootaxa 4755 (3), pp. 401-453 : 435-437

Coronatum baiensis Martins & Souto, 2012

( Figure 17 )

Coronatum baiensis Martins et al., 2012: 59–61 , figs 1–4.

Material examined. Paraíba State, Brazil: 1 spec., 701’02”S; 3447’55”W ( UFPB.ECH-2153); 4 spec., João Pessoa, 703’50”S; 3447’19”W ( UFPB.ECH-2155); 22 spec., 705’01”S; 3447’56”W ( UFPB.ECH-2154); 24 spec., 705’59”S; 3446’04”W ( UFPB.ECH-2157); 13 spec., 706’59”S; 3446’04”W ( UFPB.ECH-2151), 16 spec., 706’59”S; 3446’04”W ( UFPB.ECH-2156). Bahia State, Brazil: 1 spec., Itapo Beach, Salvador ( UFPB.ECH-2152).

Type locality. Amaralina Beach, Salvador, Bahia, Brazil (Martins et al. 2012).

Description. Based on specimens UFPB.ECH-2151. Sub-cylindrical body, small, slightly curved, 8 mm long, with 4 mm in breadth in mid-body ( Fig. 17A ). Slightly thickened skin. Color light brown to white, with few dark

spots in alcohol. Mouth terminal. Anus terminal, with five small papillae and five anal teeth. Tentacles 10, bushy, the two most ventral ones reduced. Introvert short, with some tube feet. Tube feet distributed into distinct double rows in the radii, with few irregular rows also in the interradii, more abundant and shorter ventrally. Calcareous ring complex, posterior processes not forming a tube. Radial and interradial plates attached only at the base ( Fig. 17B ). Radial plate triangular anteriorly, posterior processes divided into four small pieces. Interradial plates elongated, anterior end triangular, posterior end with a slight indentation. Madreporite bean-shaped, large, stone canal elongated. Polian vesicle single, elongated. Retractor muscles robust. Longitudinal muscle thin. Respiratory trees well branched, about 3/4 of the body length. Gonad in single tuft, tubules slender, unbranched. Body wall ossicles consist of tables with knobbed oval disc and short spire of two pillars, ending in several teeth (100 μm long) ( Fig. 17C ). Tube feet include tables of two short pillars ending in numerous teeth (105 μm long) ( Fig. 17G ), perforated supporting plates ( Fig. 17H ) and endplate (190 μm long) ( Fig. 17I ). Introvert with rosettes, tables of rounded disc and spire ending in few teeth, some with knobbed margin (80 μm long) ( Fig. 17D ). Tentacles include perforated rods, with about 25 holes in each end, smaller in the ends ( Fig. 17E ) and rosettes ( Fig. 17F ).

Morphological variations. A total of 81 specimens were analyzed, the size varied from 6–20 mm long, 2–8.5 mm in breadth in mid-body, 2–4.5 mm in breadth in anterior end, and 1–3 mm in breadth in posterior end. The color varied from brown to white, irregular dark spots also can be present along the body.

Geographical distribution. From Salvador in Bahia State to Paraíba coast. The species was found down to 10 m deep.

Remarks. Martins et al. (2012) observed that the initial part of posterior processes of the calcareous ring of C. baiensis is situated more anteriorly in large specimens. Furthermore, the length of these posterior processes and number of pieces varies among specimens of different sizes. The radial and interradial plates can be attached at base or along their whole length, not depending on size of specimen.

Ecological note. Here, the specimens of C. baiensis were found inside rhodoliths, at 10 m depth, co-occurring with Pentamera paraibanensis Prata & Christoffersen, 2016 and Pseudothyone belli ( Ludwig, 1887) . Martins et al. (2012) found the species under rocks, into crevices and buried with tentacles extended to the surface.

Figures

FIGURE 17. Coronatum baiensis Martins & Souto, 2012, UFPB.ECH-2151. A, external view of the animal; B, calcareous ring; C, tables from body wall; D, tables from introvert; E, rods from tentacles; F, rosette from tentacles; G, supporting tables from tube feet; H, supporting plate from tube feet; I, endplate.