Thysanocardia nigra (Ikeda)

Hsueh, Pan-Wen & Kuo, Chia-Ming, 2009, New records of sipunculan worms from Taiwan, Zootaxa 2067, pp. 51-61 : 57

Thysanocardia nigra (Ikeda)

Fig. 2 F

Thysanocardia nigra Cutler, 1994 : Cutler 1994: 103 –105, fig. 25D, E (for complete synonymy).

Material examined. One specimen (NMNS-4478-016), offshore Station 7 from Taichung Harbour, Taichung County, central western Taiwan, bottom dredge (20 m in depth), medium sand bottom, coll. C.-S. Kuo, 20 Aug. 2004.

Remarks. Among the three recognised species in the genus, Thysanocardia nigra and T. catharinae are relatively large in body size; their adults have a trunk length often exceeding 15 mm, compared to less than 15 mm in T. procera . Moreover, the former two species can be readily separated by the presence of dark pigment in T. nigra . The specimen examined in the present study is a large worm, with its trunk length measuring 63.5 mm. Other morphological features, such as the gray trunk ( Fig. 2 F), the presence of long branched contractile vessel villi and a dark-pigmented tentacular crown ( Cutler 1994: 104, fig. 25D, E), indicate its identity as T. nigra .

This species was previously reported from the east coast of the Pacific (northern California to Washington), as well as from islands (central and northern Japan, Philippines, Indonesia and Singapore) in the western Pacific ( Cutler 1994). The finding of this species in Taiwanese waters is not surprising.

Figures

FIGURE 2. A, Sipunculus robustus Keferstein. B, Siphonosoma funafuti (Shipley). C, Siphonosoma vastum (Selenka and Bülow). D, Golfingia margaritacea margaritacea (Sars). E, Golfingia muricaudata (Southern, 1913). F, Thysanocardia nigra (Ikeda). Scalebars: A-E, 10 mm; F, 2.5 mm. G, Themiste minor minor (Ikeda), H, Phascolosoma arcuatum (Gray). I, Phascolosoma glabrum glabrum (Sluiter). J, Aspidosiphon (Aspidosiphon) muelleri Diesing. K, Aspidosiphon coyi de Quatrefages. Scalebars: G, 5 mm; H – J, 10 mm; K, 2.5 mm.