Branchiomma bairdi (McIntosh, 1885)

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 : 2320-2322

Branchiomma bairdi (McIntosh, 1885)

( Figure 13 )

Branchiomma bairdi ; Tovar-Hernández & Knight-Jones 2006: 13–17, figs 3a–d, h–k, 9c–f, 10c, 11b; Tovar-Hernández et al. 2009: 3–8, figures 2–4.

Branchiomma boholense ; Çinar 2005: 151 (not Grube 1878).

Material examined

ESFM-POL/2005-285 , 9 September 2005, I skenderun Bay, G1, 36°35′37″ N, 36°11′09″ E, 8 m, mud, 1 specimen ; ESFM-POL/05-577 , 11 September 2005, K4, 0.5 m, ropes, 18 specimens ; ESFM-POL/2005-425 , 13 September 2005, K 7, 1m, Cystoseira sp. , 1 specimen ; ESFM-POL/05-539 , 15 September 2005, K10, 0–1 m, rocks, 1 specimen ; ESFM-POL/2005-1128 , 17 September 2005, K13, 0.2 m, tyres, 3 specimens ; ESFM-POL/2005-584 , 18 September 2005, K15, 0.2–3, rocks, 8 specimens ; ESFM-POL/2005-2324 , 24 September 2005, K30, 0.1 m, H. scoparia , 8 specimens ; ESFM-POL/2005-2761 , 29 September 2005, K37, 0.1– 3 m, rocks, 3 specimens ; ESFM-POL/2005-2315 , 3 October 2005, K44, 0.1 m, Cy. elegans , 2 specimens ; ESFM-POL/2005-2730 , 7 October 2005, K53, 0.1 m, Cy. elegans , 8 specimens .

Additional material examined

Branchiomma boholense ESFM-POL /98-49, 13 July 1998, northern Cyprus, Girne Harbour , 0.2 m, Padina pavonica , 1 specimen; ESFM-POL/98-48 , 19 July 1998, northern Cyprus, Karpas Cape , 0.1 m, rocks, 1 specimen; ESFM-POL/98-188 , 21 July 1998, northern Cyprus, Malazgirt , 2 m, rocks, 1 specimen .

Description

Largest specimen complete, 33 mm long (crown 12 mm long, thorax–abdomen 21 mm long), 2 mm wide, with 63 chaetigers (thorax with eight chaetigers) ( Figure 13A ). Tube leathery, covered by sands and algae. Body pale brownish with small dark brown spots over whole surface (especially anterior ventral part) ( Figure 13A ). Crown with brown bands alternating pale brownish bands around radioles ( Figure 13A,B ). Radiolar crown united at base by a short web, bearing 24 pairs of radioles with apinnate tips and stylodes. Basal stylode small, unpaired, digitiform. Macrostylodes strap-like, four or five times longer than other stylodes ( Figure 13A,B ). Eyes small, compound, not present between last pair of stylodes and radiolar tip. Dorsal lips long, about half the length of radioles, tapering. Dorsal collar with free, wellseparated margins. Thorax with eight segments, with interramal dark spots. Ventral shields rectangular, anterior margin of first shield straight. Collar chaetae slender, weakly geniculate, arranged in compact fascicles. Thoracic notochaetae arranged in irregular oblique rows of superior and inferior chaetae; each superior chaeta slender, weakly geniculate, knee region wider than shaft; knee region of inferior chaetae twice as wide as shafts. Neurochaetae with avicular uncini; crest surmounted by two rows of teeth ( Figure 13C ). Abdominal tori smaller than thoracic tori. Fascicles of abdominal chaetae forming compact tufts; outer geniculate chaetae arranged in C-shaped arcs. Abdominal uncini similar to those in thorax. Faecal groove passing around right side of body from last thoracic segment to second segment of ventral abdomen and onto bilobed pygidium.

Remarks

Branchiomma bairdi is very similar to B. boholense , which was previously reported from different parts of the Mediterranean (see Knight-Jones et al. 1991; Çinar 2005). Both species have macrostylodes on radioles. The main differences between these two species were recently outlined by Tovar-Hernández et al. (2009). According to them, B. bairdi has strap-like macrostylodes and two or three rows of teeth on thoracic uncini, whereas B. boholense has tongue-like macrostylodes and one large tooth on thoracic uncini. I re-examined specimens that were collected from northern Cyprus in 1998 and identified as B. boholense (see Çinar 2005), and realised that all specimens belong to B. bairdi , not B. boholense . Therefore, the previous records of B. boholense from the Mediterranean should be checked.

Distribution

This species was previously known from the western Atlantic (from Bermuda to Caribbean Sea) and eastern Pacific Ocean (Pacific Panama and Mexico) (Tovar- Hernández et al. 2009). It is a new record for the Mediterranean Sea. It could have been introduced to the area on the hulls of ships. However, if it exists in the Red Sea (no record yet), its introduction to the area through the Suez Canal cannot be excluded.

Figures

Figure 13. Branchiomma bairdi: (A) anterior part, dorsal view (ESFM-POL/05-577), (B) straplike macrostylode, (C) thoracic neurochaetae. Scale bars: (A) 1.5 mm, (B) 0.5 mm, (C) 45 µm.