Aspidosiphon laevis

<p>This species has only compressed unidentate hooks arranged in rings, well defined anal and caudal shields with extensive grooves or furrows, and two retractor muscles united for most of their length. <em>Aspidosiphon laevis</em> is a widespread species, but is usually present in low densities in tropical shallow waters.</p>

Sumber: Sipuncula

CURA Ç AO: EBC – STA 301: 29 / xii / 87; Carambi Institute in front of laboratory; (1). CUMAN Á: EBC – STA 311: 5 / i / 88; Playa Colarada, west of Mochima; (2). STA 313: 7 / i / 88: Playa Colarada, west of Mochima; (1).

Sumber: Sipunculans of the Caribbean coast of Venezuela and Curaçao

Distribution. Aspidosiphon (Paraspidosiphon) laevis inhabits coral rock and has a widespread warm water distribution. In the western Atlantic and Caribbean it is known from the Cape Hatteras region (USA) to Brazil. It has also been reported from the western Pacific Ocean. Rice (1975) collected 5 specimens of this species from intertidal Porites rubble at Spaansche Water, Curaçao.

Sumber: Sipunculans of the Caribbean coast of Venezuela and Curaçao

Description. This species has a yellow to light tan body with a brown anal and caudal shield. The grooved anal shield has a pronounced ridge-like border posteriorly and is followed by scattered low shield units, which transition to numerous low papillae in the anal region; papillae absent in posterior half of body. Caudal shield with well developed concentric ridges radiating from its center and a distinct anterior border followed by several rows of rectangular units anterior to the ridge. Hooks are unidentate with a wide base. Retractor muscles are united until adjacent to their attachment at about 60 % of body length as a broad sheet to the body wall; nerve cord passes through the narrow gap between the retractors at their separation. Anterior spindle muscle attaches along the rectum and sends a branch that attaches broadly anterior to the anus. Habitat. Subtidal calcareous rock, 8 - 20 m.