Molpadia thandari Samyn & VandenSpiegel

Samyn, Yves & Vandenspiegel, Didier, 2016, Sublittoral and bathyal sea cucumbers (Echinodermata: Holothuroidea) from the Northern Mozambique Channel with description of six new species, Zootaxa 4196 (4), pp. 451-497 : 491-492

Molpadia thandari Samyn & VandenSpiegel sp. nov.

( Fig. 33 A – C)

Molpadia sp. indet.; Thandar, 2007: 52, fig. 24

Material examined. Type material: IE-2007-759 (holotype, sampled in front of Nazendry Bay ); IE-2007-806 (1 paratype, sampled in front of Nazendry Bay)

Type locality. Madagascar, Nazendry Bay , Station CP 3289 (Decimal coordinates: -14,4833; 47,4333)

Etymology. This species is named after Prof. Em. Ahmed S. Thandar of the University of KwaZulu-Natal in South Africa, who, in 2007, was the first to recognize this species as a separate taxon.

Known geographic description. Known from off Tongaat Bluff just North of Durban (Decimal coordinates: - 29.73; 31.42) to Nazendry Bay near Nozi Lava (Decimal coordinates; -14,4833; 47,4333)

Taxonomic description (holotype and paratype). Anatomy — Holotype 70 mm long and 35 mm wide with tail 5 mm long. Paratype 25 mm long and 12 mm wide, with tail 2 mm long (fig. 33A). Body uniform light chocolate brown, with tail somewhat lighter in color. Muscle bands can be seen through the body wall. Tentacles 15, retracted, morphology could not be determined. Anus surrounded by five minute and slender teeth. Calcareous ring with, plates fused, radials with a terminal bifid posterior projection (broken in holotype); interradial with triangular anterior projection of same length of that of radial plate. 15 short tentacle ampullae; Polian vesicule single, elongated; stone canal not detected. Left respiratory tree reaching mid body, right longer. (see also Thandar (2007) for Molpadia sp. indet.) Gonad well-developed, branching. Longitudinal muscles divided into two lateral bands that unite before reaching the calcareous ring.

Ossicles —Ossicle assemblage of tentacles could not be determined. Body wall with tables of two different morphologies. The first type has their disc, 123 – 176 µm wide, perforated with 4 to 6 holes and with four to six arms 132 – 208 µm long. Disc spire is made of 3 pillars fused over their complete length, 253 – 300 high (no trace of cross-beams can be seen). The second type of table does not have long disc arms and has their discs perforated by 3 – 5 large holes, 42 – 74µm- wide; spire again consistng of three fused pillars, 113 – 129µm high. Tables from the tail are the typical fusiform Molpadia type, 360 – 412 µm long, with disc slightly swollen centrally and perforated by 2 – 4 small holes; spire low, 37 – 51 mm high, ending in four teeth.

Remarks. We agree with Thandar (2007) that the large body wall tables with multi-armed discs and 4 – 6 holes make this species stand aside from other Molpadia species. We feel it justified to regard this character state important enough to warrant it diagnostic for a species new to science.

We decided to picture only the paratype, because the dissected holotype might give a wrong impression of the species.

Figures

FIGURE 33. Molpadia thandari sp. nov. A: Dorsal view of the paratype; B – C: SEM photos of ossicles from dorsal body wall (B) and tail (C). Scale bars: A = 1 cm; B, C = 50 µm.