Cloeosiphon aspergillus

Adrianov, Andrey V. & Maiorova, Anastassya S., 2012, Peanut worms of the phylum Sipuncula from the Nha Trang Bay (South China Sea) with a key to species, Zootaxa 3166, pp. 41-58 : 55

Cloeosiphon aspergillus (de Quatrefages, 1865)

( Fig. 6 C–D)

Material. Nha Trang Bay: Mot Island, coral rubble, 7 m, May 2008, 12 specimens; Tre Island, coral rubble, 6 m, Jun 2008, 18 specimens; Tre Island, biofouling, intertidal, Nov 2009, 6 specimens; Mung Island, coral rubble, 12 m, May 2008, 15 specimens; Nok Island, coral rubble, 5 m, 8 specimens; Diamond Bay: coral rubble, intertidal, Jun 2008, 25 specimens; Nov 2009, 16 specimens; Mar 2010, 8 specimens.

Description. Trunk up to 70 mm long, 4–5 mm wide, light brown or grey, with minute brown papillae, semitransparent; introvert shorter than trunk. Anal shield consists of white rhomboid or polygonal mosaicly arranged, calcareous units, with a dark central pore; caudal shield absent. Introvert protruded through the center of the anal shield; bidentate hooks arranged in rings distally. Longitudinal musculature continuous; retractor muscles originate in the middle of the trunk. Gut with 10 loops. Nephridia are about 70–90% of trunk length, completely attached to the body wall.

Discussion. This is the only species of the genus Cloeosiphon , and because of its unique configuration between the anal shield and the introvert by far the most distinctive species of sipunculans.

This tropical species is widely distributed in the Indo-West Pacific. In the West Pacific it has been reported from Australia to Hainan Island, inhabiting coral rocks in shallow water.

Figures

FIGURE 6. A – B. Lithacrosiphon cristatus. A) lateral view, introvert everted; B) hooks. C – D. Cloesiphon aspergillus. C) lateral view, introvert retracted; D) hook. Scale bars: A, 5 mm; B, 20 µm; C, 2 mm; D, 20 µm.