Sipunculus norvegicus

Sipunculus (Sipunculus) norvegicus Danielssen, 1869

Languages: English

Overview

General Description

This species is a small, semi-transparent worm, from cold and deep water. The main distinguishing external character is the posterior glans region that is marked off from the trunk by a ridge.

Author(s): Kawauchi, Gisele Y.
Rights holder(s): Kawauchi, Gisele Y.

Type

Type Material

Types: Museum of Zoology, University of Bergen, Bergen, Norway, ZMUB 1671 (Cutler and Cutler, 1985).

Author(s): Kawauchi, Gisele Y.
Rights holder(s): Kawauchi, Gisele Y.

Description

Morphology

(From Stephen and Edmonds, 1972; Cutler, 1994)

 

External anatomy

Introvert shorter than the trunk (about a quarter as long as the body). Conical papillae cover the surface.

Trunk is cylindrical, up to100 mm in length, and transparent. The surface of the trunk is divided into a large number of small rectangles by the intersection of the longitudinal and circular muscles.

Glans region (a smooth posterior tip) usually marked off from the trunk by a ridge, and may or may not be interrupted ventrally by a furrow.

Tentacular crown is divided into 8 to 12 lappets or lobes.

 

Internal anatomy

20-24 longitudinal muscles bands (LMBs), commonly 21-22.

A pair of short and free nephridia.

Brain is elongated, flattened. The lobes are not prominent, and the processes are not developed.

Ventral retractor muscles originate in LMBs 3 and 4, and dorsal retractor muscles from LMBs 8 and 9.

Author(s): Kawauchi, Gisele Y.
Rights holder(s): Kawauchi, Gisele Y.

Size

This is a small species, usually less than 100 mm in length (Cutler and Cutler, 1985).

Author(s): Kawauchi, Gisele Y.
Rights holder(s): Kawauchi, Gisele Y.

Ecology and Distribution

Distribution

Most records are from the North Atlantic, from the equator to 57ÂșN, but there are scattered records from Red Sea, Mediterranean, Indian, and western Pacific Ocean (Cutler, 1994).

Author(s): Kawauchi, Gisele Y.
Rights holder(s): Kawauchi, Gisele Y.

Habitat and Ecology

This species is from deep and cold water from sublittoral and bathyal waters, 100-3000 m (Cutler, 1994). 

Author(s): Kawauchi, Gisele Y.
Rights holder(s): Kawauchi, Gisele Y.

References

Cutler, E. B. (1994).  The Sipuncula. Their systematics, biology and evolution. 453 pp. Ithaca, N.Y.: Cornell University Press.
Cutler, E. B., & Cutler N. J. (1985).  A revision of the genera Sipunculus and Xenosiphon (Sipuncula). Zoological Journal of the Linnean Society. 85, 219-246.
Stephen, A. C., & Edmonds S. J. (1972).  The phyla Sipuncula and Echiura. 528 pp. London: Trustees British Mus. (Nat. Hist.).