Sipunculus robustus

Sipunculus (Sipunculus) robustus Keferstein, 1865

Languages: English

Overview

General Description

This species is sometimes confused with S. nudus, but the free nephridia, a different number of LMBs, and the characteristic digitate processes of the brain are distinguishing characters of S. robustus.

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

Type

Type Locality

Uea, Wallis Island, Pacific Ocean (Stephen and Edmonds, 1972).

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

Type Material

Type: Zoologische Institut Zoologisches Museum, Universitat von Hamburg, Hamburg, ZMUH (Cutler, 1985).

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

Description

Morphology

(From Stephen and Edmonds, 1972; Cutler and Cutler, 1985 and Cutler, 1994).

 

Introvert shorter than the trunk, with triangular papillae covering the surface.

Trunk is cylindrical and the surface is divided into a large number of small rectangles by the intersection of the longitudinal and circular muscles.

 

Internal anatomy

26-30 longitudinal muscle bands, usually 28-29.

A pair of free nephridia.

Brain with long and stringy lateral processes.

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

Similar Species

This species is similar to Sipunculus nudus, however it is differentiated by the number of LMBs, the free nephridia, and the lateral long stringy brain processes.  Cutler and Cutler (1985) believe that over the years S. robustus has been mistakenly identified as S. nudus and vice versa.

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

Ecology and Distribution

Distribution

This species is found in warm shallow waters in the Indo-West Pacific Ocean, Red Sea, and Caribbean.

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.).