| 鉴别 |
Mean live weight 700 to 1,200 g; body thickness 0.5 cm. Body elongate, cylindrical, slightly arched dorsally (bivium) and flattened ventrally (trivium). Bivium generally covered by fine sediment. Papillae on bivium small, slender, and conical; cylindrical and thick podia on trivium arranged irregularly on the radii and interradii; calcareous disc of podia around 700 micrometer in diameter. Mouth ventral, surrounded by 20 stout tentacles. Anus sub dorsal, surrounded by 5 strong, triangular, and nodose anal teeth. Calcareous ring thick, with large radial pieces and narrow interradials. Cuvierian tubules absent. Bivium black; trivium dark brown. Spicules sparse in the ventral and dorsal tegument, abundant only near the mouth, anus, and tentacles; a few rods in the dorsal tegument give rise to numerous rosettes, rods, and various plates; small to large plates provided with holes and spines near the anus; tentacles with rods straight or arched, bearing small spines. |
