ΑγγλικάMean live weight 300 to 1000 g; body-wall thickness 0.4 cm. Body cylindrical, very elongate, larger near the posterior end. Tegument very tough. Papillae on bivium short; emerging from warts; podia on trivium conical, stout, yellow, arranged in 10 rows on the radii and interradii; calcareous disc of podia around 400 micrometer in diameter. Mouth ventral, surrounded by 20 very long, stout tentacles of characteristic yellow color; mouth also surrounded by a collar of small papillae. Anus surrounded by 5 groups of 3 small papillae. Calcareous ring with large and high radial pieces and narrow interradials. Cuvierian tubules absent. Black, with yellow podia. Spicules on tegument with tables and pseudo-buttons; tables with circular discs showing 8 holes, bearing a spire of 4 pillars, with spiny crown, hollow in the middle; pseudo-buttons plate-like with denticulate border; rods in the podia and papillae smooth, with holes at their ends; tentacles with nodulous rods.