Streblosoma comatus ( Grube, 1856 )

Çinar, Melih Ertan, 2009, Alien polychaete species (Annelida: Polychaeta) on the southern coast of Turkey (Levantine Sea, eastern Mediterranean), with 13 new records for the Mediterranean Sea, Journal of Natural History 43 (37 - 38), pp. 2283-2328 : 2313-2314

Streblosoma comatus ( Grube, 1856)

( Figure 10 )

Terebella comata Grube 1856: 109 .

Thelepus comatus ; Day 1967: 729, fig. 36.5.j–n.

Streblosoma comatus ; Glasby and Hutchings 1987: 977–986.

? Streblosoma hesslei ; Giangrande et al. 1981: 314–316, figs 7–9. (not Day 1955).

Material examined

ESFM-POL/2005-481 , 15 September 2005, K 10, 1 m, Sarcotragus sp. , 1 specimen ; ESFM-POL/2005-582 , 15 September 2005, K 10, 1 m, Sarcotragus sp. , 47 specimens ; ESFM-POL/2005-488 , 15 September 2005, K 11, 1 m, J. rubens , 1 specimen ; ESFM- POL/2005-746, 17 September 2005, K13, 0.2 m, tyres, 3 specimens; ESFM-POL/ 2005-2347 , 28 September 2005, K36, 0.3 m, Cy. elegans , 62 specimens ; ESFM-POL/ 2005-2297 , 5 October 2005, K50, 0.1 m, Cytoseira crinita , 3 specimens .

Description

Largest specimen incomplete, 44 mm long, 1.8 mm wide, with 54 chaetigers. Body brownish, widest mid-anteriorly, tapering posteriorly. Prostomium short, transversely grooved, directed ventrally. Buccal tentacles grooved. Eyespots arranged in narrow band across tentacular collar. Peristomium similar to chaetiger 1 dorsally, forming a crescent-shaped lower lip. Lateral lobes absent. Three pairs of branchiae on segments 2–4, consisting of simple filaments; 25 on segment 2, 24 on segment 3 and 20 on segment 4 ( Figure 10A ). Medial gap between left and right side groups of filaments wider on segment 4. Notopodia from segment 2 to near pygidium, with winged capillaries ( Figure 10B ). Neurochaetae from chaetiger 4, avicular, extending near pygidium; having a main fang with two rows of teeth above, two in first row and six in second row ( MF: 2: 6) ( Figure 10C ). Uncini arranged in single rows, longest mid-anteriorly, decreasing in length and forming C-shaped curves at chaetiger 16 to end of body ( Figure 10C ). Midventral glandular pads extending to segment 19. Nephridial papillae absent. Pygidium (in complete specimens) without cirri, cylindrical, anus terminal.

Distribution

Streblosoma comatus was previously reported from the Indian and Pacific Oceans ( Day 1967). The report of S. hesslei Day, 1955 from the Italian coast by Giangrande et al. (1981) might refer to this species. However, Giangrande et al (1981) did not give any information regarding the number of segments with notochaetae, which is one of the main differences between S. comatus and S. hesslei . Therefore, the specimens from the Italian coast should be re-examined to see whether they have notochaetae in the posterior part of the body. This species might have been introduced to the Mediterranean in the ballast waters of ships from the Indian Ocean. However, if it occurs in the Red Sea (no record to date), its introduction via the Suez Canal could not be excluded.

Figures

Figure 10. Streblosoma comatus: (A) anterior part, lateral view (ESFM-POL/2005-582), (B) winged capillary chaeta on notopodium of chaetiger 15, (C) neurochaetae on chaetiger 20. Scale bars: (A) 2 mm, (B) 18 µm, (C) 70 µm.