Lihacrosiphon cristatus ( Sluiter, 1902 )

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 : 54

Lihacrosiphon cristatus ( Sluiter, 1902)

( Fig. 6 A–B )

Material. Nha Trang Bay: Mot and Tre Islands, 4–7 m depth, coral rubble.

Description. Trunk 10–15 mm long, 3–4 mm wide, light brown, semitransparent; introvert subequal to trunk length. Anal shield furrowed longitudinally with about 20 grooves and often covered by red, yellow and white calcareous deposit which masks these grooves. Bidentate hooks arranged in rings on the distal introvert; unidentate hooks scattered over the proximal introvert. Longitudinal musculature splits into 15–20 anastomozing bands. Retractor muscles originate 10% of trunk length from the caudal shield. Nephridia are about 40–45% of trunk length.

Discussion. The species differs from the other representative of this genus, Lithacrosiphon maldivensis , in structure of the anal shield, which is ungrooved, granular, and bullet-shaped in L. maldivensis .

Lithacrosiphon cristatus is a tropical species, known from the Atlantic and Pacific Oceans. In the West Pacific it has been reported from Indonesia to southern Japan. It can be found inside 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.