Holothuria (Theelothuria) hamata Pearson, 1913

Aydin, Mehmet, Gurlek, Mevlut, Samyn, Yves, Erguden, Deniz & Turan, Cemal, 2019, First record of a Lessepsian migrant: the sea cucumber Holothuria (Theelothuria) hamata Pearson, 1913, Zootaxa 4551 (1), pp. 94-100 : 95-96

Holothuria (Theelothuria) hamata Pearson, 1913

Holothuria hamata Pearson, 1913: 51 , pl. 5; Pl. 6, fig.2; Cherbonnier, 1955: 156, pl. 39, figs a–m, pl. 40, figs n–w; Domantay,

1957: 429; Cherbonnier, 1959: 250; Daniel and Halder, 1974: 417. Holothuria (Holothuria) hamata ; Panning, 1935: 83, fig. 70a–e. Holothuria (Theelothuria) hamata ; Rowe, 1969: 158; Clark and Rowe, 1971: 179; Sloan, Clark, & Taylor, 1979: 123; Price,

1982: 11; Rowe and Gates, 1995: 300; Samyn, 2003: 78, 80, 121. Holothuria ocellata ( Jaeger, 1833) ; Teo and Ng, 2009: 411–414, fig. 2 (non Holothuria ocellata ).

Status and location of name-bearing types: 2 syntypes in Colombo Museum , Colombo, Sri Lanka, according to Rowe and Gates (1995) .

Type locality: Suez .

Material examined. 1 specimen, Arsuz coast ( Hatay), Iskenderun Bay (36 o 25' 085” N–35 o 52' 588” E) on 11 November 2017, 30 m depth, buried in sand. (Note: the sampled individual was kept in seawater at -18 ° C for 2 months. We observed that it retained its external characteristics and color throughout this time-frame)

General Description. Unique specimen medium to large, well relaxed, ± 21 cm long and ± 4,5 cm wide. Body elongate, tapering at both ends; bivium convex ( Figure 2A ), trivium flattened ( Figure 2B ). Body colour in life: dorsal grayish to yellowish-brown with prominent conical brown papillae with lighter tip and surrounded by a narrow light-grey band in which irregularly placed dark grey spots are present; ventral surface greenish-grey medially and light-gray laterally, speckled with minute irregularly placed grey spots; papillae on mid-ventral body whitish-green, bordered by a greenish ring which in turn is bordered by a lighter rim that contrasts with the darker background; lateral papillae light-gray in colour. Body wall 2–4 mm thick, gritty to the touch. Mouth ventral and anus terminal, both mouth and anus surrounded by papillae. Bivium and trivium separated by a single rim of large, long papillae, some of them fused at their base; ventrally some smaller papillae intercalate in the interambulacrum; lateral papillae ± 20 in number on each side. Papillae of trivium predominantly in ambulacral areas, but with some spreading into the interambulacral areas, arrangement in 5 rows, about 25 papillae per row. Papillae of bivium only in ambulacral areas, in 2–3 irregular rows; some 30 papillae per row. All dorsal, lateral and ventral papillae nonretractle. Cuvierian tubules absent. Structure of calcareous ring, structure and number of stone canals, madreporite(s), Polian vesicle(s), not studied.

Ossicles: Tentacles with spiny rods, 237–526 µm long ( Figure 3A ). Ventral and dorsal body wall with similar tables and buttons. Tables ( Figure 3B, C ) with spiny disc, 80–110 µm across, perforated by four central holes and 9–14 peripheral holes; disc flat; spire with a single cross-beam ending in a wide crown adorned with numerous teeth/spines; spire often spiny also at base giving the table a ‘compact’ very spine/thorny look ( Figure 3D ). Buttons knobbed or somewhat spiny, regular, with 3 pairs of holes, 135–255 µm long and 77–134 µm wide. Some buttons modified to ellipsoids with up to five pairs of holes and with both lateral and medial nodules, such buttons 25–44 µm long and 14–26 µm wide ( Figure 3E ).

Papillae with rods, plates and tables. Rods ( Figure 3F ) perforated throughout their length, 200–338 µm long, but some only with enlarged and perforated central part. Most tables of papillae with discs 80–110 µm in diameter and spires 97–120 µm high. Some tables different from those of the body wall with their disc generally less spiny or smooth, more perforated and with a tall attenuating spire provided with several cross-beams; giving the table a typical tack-like appearance; discs of such tables have a wide undulating rim 135–168 µm in diameter, perforated by numerous holes; the spire terminating in a narrow point ( Figure 3G ).

Distribution: Suez Bay ( Pearson, 1913; Panning, 1935; Cherbonnier, 1955, 1959), Red Sea ( Rowe, 1969), Maldives ( Clark & Rowe, 1971), Seychelles, Aldabra ( Sloan et al., 1979), Kenya? ( Samyn, 2003); Indian Ocean, exact locality not specified ( Domantay, 1957); Northern Australia ( Rowe & Gates, 1995).

Rowe and Gates (1995) note a bathymetric distribution from 9– 190 m.

Figures

FIGURE 2. Holothuria (Theelothuria) hamata Pearson, 1913. A. Dorso-lateral view; B. Ventral view (Photo’s by M. Aydin)

FIGURE 3. Holothuria (Theelothuria) hamata Pearson, 1913. A. Rods of tentacles; B. Tables of dorsal body wall; C. Tables of ventral body wall; D. ‘Compact-look’ table; E. Buttons/fenestrated ellipsoids of dorsal body wall; F. Perforated rods of papillae; G. Lateral view of tag-like tables of papillae. Scale bars B–E represent 50 mm; scale bars F& G 100 mm.