Stichopus chloronotus Brandt, 1835

Woo, Sau Pinn, Yasin, Zulfigar, Tan, Shau Hwai, Kajihara, Hiroshi & Fujita, Toshihiko, 2015, Sea cucumbers of the genus Stichopus Brandt, 1835 (Holothuroidea, Stichopodidae) in Straits of Malacca with description of a new species, ZooKeys 545, pp. 1-26 : 3

Taxon classification Animalia Aspidochirotida Stichopodidae

Stichopus chloronotus Brandt, 1835 Figs 2, 3

Holothuria (Holothuria) quadrangularis Lesson, 1830: 90, pl 31, fig. 1.

Stichopus (Perideris) chloronotus Brandt, 1835: 250.

Stichopus chloronotus ; Selenka 1867: 315, pl. 17, figs 20-24; 18, fig. 25; Pearson 1903: 204; Panning 1944: 30, fig. 3 a–e; Loi and Sach 1963: 238, pl. 1, fig. A, pl. VI, fig. 1; Clark and Rowe 1971: 178, pl. 27, fig. 18; Mary Bai 1980: 16, fig. 101; Tan Tiu 1981: 65, pl. 7, figs 1-3; Clark 1984: 99; Féral and Cherbonnier 1986: 94; Cannon and Silver 1986: 27, fig. 4h; Cherbonnier 1988: 146, fig. 60 A–O; James and James 1994: 12, pl. VI; Kerr 1994: 163; Rowe and Gates 1995: 323; Massin et al. 2002: 74, figs 1-2, pl. 1A.

Stichopus cylindricus Haacke, 1880: 47.

Stichopus chloronotus var. fuscus Pearson, 1903: 204.

Stichopus hirotai Mitsukuri, 1912: 161.

Holothuria viridis Cherbonnier, 1952: 19-21, fig. 7.

Material examined.

Five specimens: USM/MSL/PB004, USM/MSL/PB005, USM/MSL/PB006, USM/MSL/PB007, USM/MSL/PP005.

Type locality.

Lugunor Islands, Guam.

Description.

External morphology: Body quadrangular in cross-section with four distinctive sides; smooth, firm, and hard, indicating thick integument; dark blue in colour underwater and almost black out of water (Fig. 2). Large and long papillae at dorso-lateral edge running from collar of tentacles toward anus in two rows; similar papillae at ventro-lateral edge but in one single row; tip to base of papillae yellow to ochre in colour. Ambulacral areas with tube feet and narrow interambulacra; central ambulacrum wider compared to other two ambulacra. Oral opening with 20 peltate tentacles on ventral side; anus at terminal.

Spicules: Dorsal body wall with tables, C-shaped rods, and S-shaped rods (Fig. 3 A–C). Tables abundant in dorsal body wall; base smooth with four large central perforations and 4-10 smaller peripheral holes; four pillars forming spires, joined with one crossbeam; tip of each pillar spiny. C-shaped rods smooth with sharp endings; some being irregular in form. S-shaped rods derived from C-shaped rods present. Dorsal papillae bearing C-shaped rods, S-shaped rods, elongated rods, and tables (Fig. 3 D–G). Tables in dorsal papillae with large disc, four central perforations, and multiple peripheral holes; pillars joined by one, sometimes incomplete, crossbeam; tip of pillars with multiple large spines. Ventral tube feet bearing plates, thick rods, tables, and C-shaped rods (Fig. 3 H–J). Large plates in ventral tube feet having distinctive larger central perforations; numerous smaller peripheral holes distributed over plates. Other smaller plates in ventral tube feet having perforations similar in size to each other. Edges of plates in ventral tube feet jagged but less pointy and sharp. Tables in ventral tube feet having reduced pillars or no pillar; one crossbeam incompletely joining all pillars; four central perforations with less peripheral holes compared to tables from dorsal body. Rods in ventral tube feet with 0-3 (mostly one) perforation(s) at central extension (Fig. 3I). Tentacles with tables and rods. Tables in tentacles reduced to only disk without pillars, with four central perforations surrounded by smaller peripheral holes; similar to tables in dorsal body wall (Fig. 3F). Rods in tentacles in various sizes, with spiny and rough surface; smaller rods straight while larger rods slightly curved (Fig. 3L).

Remarks.

Stichopus chloronotus is fairly easy to be identified in situ due to the bright, distinctive green-blue colouration on the body with yellowish coloured papillae (Fig. 2A), although there are some colour variations in the papillae across different localities ( Massin et al. 2002). This species is distinguished from the other congeneric species also by its smooth body.

Large spicules with elaborated sculpted surface in the tentacles reported from Madagascar by Cherbonnier (1988) were not found in our specimens. This type of spicule is also missing from other descriptions by Théel (1886), Massin (1996) and Massin et al. (2002).

Distribution.

This is a common species found throughout the Indo-West Pacific area ( Clark and Rowe 1971).