Holothuria

THANDAR, AHMED S., 2007, Additions to the aspidochirotid, molpadid and apodid holothuroids (Echinodermata: Holothuroidea) from the east coast of southern Africa, with descriptions of new species, Zootaxa 1414 (1), pp. 1-62 : 42-44

Holothuria (? Theelothuria ) sp. indet.

Figure 19

Material examined SAM A-27944, Park Rynie, southern KwaZulu-Natal, K.S. Ganga, July 1982, 1 spec.

Description

Specimen 20 x 8.5 mm, apparently preserved long after death, eviscerated and badly distorted, hence what appears to be the dorsal surface is actually ventral and vice versa,. Colour uniformly yellowish-white. Skin damaged, parchment-like and translucent. Mouth ventral, encircled by 17 pale yellowish-white tentacles, darker distally, collar absent. Anus terminal, no special anal papillae. Dorsal podia small, few, scattered; ventral podia better developed, confined to ambulacra in 2–3 rows ventro-laterally, two rows in odd ambulacrum, few also scattered in interambulacra.

Body cavity filled with coarse sand, small stones, broken shells and coral debris. Calcareous ring ( Figure 19G ) damaged but showing broad quadrangular radials, each with a posterior concavity, anterior notch and bifurcate anterior projections; interradial plates small, enclosed by radials, each with median anterior projection.

Spicules of dorsal and ventral body wall similar, comprising mostly tables and buttons, the latter usually restricted to bases of podia. Tables of two sizes: larger ones ( Figure 19A ) with somewhat squarish, slightly upturned, spinose disc (dorsally 56–85 µm, mean 73 µm; ventrally 54–88 µm, mean 74 µm), perforated by four large central holes and nearly always a single series of large peripheral ones, spire low to moderate (dorsally 48–77 µm, mean 55 µm; ventrally 42–54 µm, mean 47 µm), with 1–2 cross-bars, ending in a perforate crown bearing numerous teeth; smaller tables ( Figure 19B ) with somewhat distorted and/or reduced smooth disc (dorsally 52–69 µm, mean 63 µm; ventrally 60–83 µm, mean 67 µm), with often upturned rims, spire low (dorsally 35–48 µm, mean 43 µm; ventrally 29–40 µm, mean 36 µm) with usually a single cross-bar, crown similar to that of larger tables. Buttons ( Figure 19D ) few, elongate (dorsally 117–131 µm; ventrally 79–119 µm), usually with more than four pairs of holes, slightly knobbed marginally and medially, with knobs often uniting to convert buttons to simple fenestrated ellipsoids. Podial deposits smooth, elongate rods (79–120 µm, mean 103 µm) with corrugated margins ( Figure 19C ), often expanded and perforated in the middle and/or at ends, rarely lacking perforations, those of ventral podia sometimes button-like with paired series of holes. End-plates present, dorsally 144–173 µm ( Figure 19E ); ventrally up to 387 µm. Tentacle deposits ( Figure 19F ) as curved, spinulated rods of various sizes (48–326 µm).

Remarks

Because of the poor state of preservation of the specimen and the fact that its calcareous ring is damaged, the subgeneric rank of this specimen is dubious. It is tentatively referred to Theelothuria because of its spinyrimmed tables and the occurrence of some buttons in the form of fenestrated ellipsoids. In this respect it comes quite close to H. (? Theelothuria ) turricelsa Cherbonnier, 1980 but differs in the absence of conical papillae on the dorsum, the more regular form of the table crowns, the height of the table spires, fewer holes on the table discs, the presence of two types of tables and the general simplicity of buttons. The specimen can also be referred to the subgenus Cystipus as was remarked for H. turricelsa by Cherbonnier (1980). The specimen also comes close to H. squamifera Semper, 1868 from the west Pacific Ocean but differs in the two forms of tables. It may also be argued that it might be a juvenile of H.(M.) nobilis but its colouration, simplicity of tables, presence of some tall-spired tables and absence of large plate-like spicules in the podia preclude its identification with this species.

Figures

FIGURE 19. Holothuria (?Theelothuria) sp. indet. SAM–A27944. A. tall-spired tables from dorsal body wall; B. shortspired tables from dorsal body wall; C. rods of the dorsal podia; D. buttons from dorsal body wall; E. end-plate from dorsal podium; F. tentacle rods; G. calcareous ring. (A–F scale a)