Branchiomma Kölliker, 1858

Keppel, Erica, Tovar, Maria Ana & Ruiz, Gregory, 2015, First record and establishment of Branchiomma coheni (Polychaeta: Sabellidae) in the Atlantic Ocean and review of non – indigenous species of the genus, Zootaxa 4058 (4), pp. 499-518 : 503-505

Genus Branchiomma Kölliker, 1858

Branchiomma coheni Tovar-Hernández and Knight-Jones, 2006: 24 –27, Fig. 6A–M, 8A, 9E–G, 10D, 11C.

Examined material. Tampa Bay, Florida, coordinates 27° 53’ 07.4" N, 82° 32’ 02.7" W (4 specimens). One specimen is from the survey of 2012 and 3 are from 2014 from the same site of 2012, nevertheless the site numbers are different numbers due to the different years, and are from 2 different plates. Site 2118 (2012): plate 15009: vial # 168941 (1 specimen). Site 2240 (2014): Plate 16838: Vial #: 158629 (1 specimen), 199914 (1 specimen); Plate 16829: 158394 (1 specimen). Some tissue was collected from 2 specimens and preserved in 95 Ethanol for possible molecular analysis (158629 and 158394) in order to have the same organism for both the analysis. The four specimens are listed in Table 1 with some size measures and observations on reproductive biology.

Comparative additional material. Panama, Punta Culebra, Naos, 08° 54.7’ N, 79° 31.8’ W, intertidal (Paratype ECOSUR 0051).

Gulf of California: Mazatlán, Sinaloa (2009), 23°12’ 13’’ N, 106° 24’ 31.4’’ W, 50 cm depth, buoy fouling (20 specimens EMU-ICML 8703, 8715, 8719, 8724, 8726, 8729); 23°12’ 13’’ N, 106° 24’ 30.1’’ W, 50 cm depth, buoy fouling (23 specimens EMU-ICML 8704, 8707, 8710, 8716, 8720, 8722); 23°11’ 48.7’’ N, 106° 24’ 31’’ W, 50 cm depth, buoy fouling (129 specimens EMU-ICML 8705, 8708, 8711, 8713, 8717, 8721, 8723, 8725, 8727, 8730, 8731, 8733; 23°11’ 8.9’’ N, 106° 24’ 55.8’’ W, 50 cm depth, buoy fouling (8 specimens EMU-ICML 8706, 8709, 8712, 8714, 8718, 8728, 8732, 8734). Topolobampo, Sinaloa (2011), 25°35’ 59’’ N, 109° 03’ 29’’ W, 50 cm depth, dock fouling (13 specimens GEOMARE-POLY-004); El Mavirí (2011), 25° 35’ 15’’ N, 109° 06’ 05’’ W, 30 cm depth, on Crassostrea gigas cultures (4 specimens GEOMARE-POLY-005). San Carlos, Sonora (2011), 27° 56’ 44.52” N 111° 5’ 32.82” W, 30 cm depth, rope (8 specimens GEOMARE-POLY-006). La Paz, Baja California Sur (2011), 24° 9' 17.76" N 110°19' 33.96" W, 50 cm depth, dock fouling (18 specimens GEOMARE-POLY-007); 24°16' 28.62" N 110°19' 51.12" W, hull fouling (11 specimens GEOMARE-POLY-008).

Diagnosis. Body length of four adult specimens varied from 37 to 50 mm. Body dark brown mottled with small brown spots ( Fig. 3 b). Interramal dark spots, larger on thoracic segments than in abdominal region. Radiolar crown (1/3 of the body length) is usually around 10 mm length. About 21–23 pairs of radioles, each banded with green olive, dark brown bands and one orange band between each pair of eyes. Basal stylodes unpaired, medium length, tongue-like, same size as rachis width. At least three foliose macrostylodes, broadening distally, sometimes with very uneven distal margins ( Fig. 3 a–c). Dorsal lips one third length of radioles, triangular with a distinct orange longitudinal ridge (mid-rib), lateral margin olive-green. Body with eight thoracic segments; collar dorsal margin well separated, ventral lappets subtriangular, fleshy and overlapping in reflexed position ( Fig. 3 b). Thoracic tori extending to sides of brown trapezoidal ventral shields. Avicular uncini with the crest surmounted by two rows of teeth, occupying one quarter of the crest and manubrium short ( Fig. 3 d).

Distribution ( Fig. 4). Eastern Pacific (Possibly native): Punta Culebra and Balboa ( Panama); Mazatlán, Topolobampo, San Carlos and La Paz (Gulf of California).

Western Atlantic (Introduced): Tampa Bay (Florida).

Habitat. Panama: intertidal, on large boulders and rocks buried in sand and associated tide pools, with smaller rocks covered by sponges and additional fouling species ( Tovar-Hernández & Knight-Jones 2006).

Gulf of California: inhabiting shallow waters (0.3–0.5 m depth) on buoys, docks, ropes, on vessel hulls and on oyster farms; salinity 32.1–34.8‰; temperature 21.5–31.5ºC; dissolved oxygen 3.15–6.66 mg /L; forming part of an assemblages of 12 introduced species: the polychaetes B. bairdi ( McIntosh, 1885) , Hydroides diramphus Mörch, 1863 , H. elegans (Haswell, 1883) , H. sanctaecrucis Krøyer in Mörch, 1863; the ascidians Botryllus schlosseri (Pallas, 1766) , Botrylloides nigrum Herdman, 1886 , B. violaceus Oka, 1827 , Didemnun perlucidum F. Monniot, 1983 and Polyclinum constellatum Savigny, 1816 ; the bryozoans Bugula neritina (Linnaeus, 1758) and Amathia verticillata (delle Chiaje, 1822); and the copepod Haplostomides hawaiiensis Ooishi, 1994 .

Florida: on settling panels (present study). Branchiomma coheni was found not in the presence of B. bairdi but was always found with the sabellid Parasabella microphthalma (Verrill, 1873) .

Remarks. According to Camp et al. (1998) and Statewide Biological Database (2013), four species of Branchiomma are reported along the coast of Florida: Branchiomma arenosa (Treadwell, 1924) , B. bairdi , B. conspersum (Ehlers, 1887) and B. nigromaculatum (Baird, 1865) . However, B. arenosa is not valid, it is a junior synonym of B. conspersum ( Tovar-Hernández & Knight-Jones, 2006) . As far as we know, Florida is a natural distribution area for all these three species; the record of B. coheni constitutes the first record of an introduced species of Branchiomma along the east coast of the US and the entire Atlantic Ocean.

Branchiomma coheni was described from the Pacific coast of Panama in 2006 and the records provided here from Tampa Bay and Gulf of California constitute the first published record since its description. As B. coheni was found at the same site in two different years and in 2014 on two different settlement panels of the five investigated in that site, we assume that it represents a case of an early detection of a NIS that appears to be established (sensu CIESM 2012).

Among the species distributed in Florida, it is easy to differentiate B. nigromaculatum from the other species because it is unique in having microstylodes and rachis with a segmented appearance. Branchiomma bairdi , B. conspersum and B. coheni present macrostylodes, but in the first these are strap-like, in B. conspersum tongue-like and in B. coheni foliose (see Fig. 9 in Tovar-Hernández & Knight-Jones 2006 for the shape of stylodes).

Figures

FIGURE 3. Branchiomma coheni found in Tampa Bay: a) stylodes; specimen 158394 (2014), b) ventral view showing thorax, collar, lappets and base of radioles; specimen 168941 (2012), c) macrostylodes, specimen 199914 (2014), d) thoracic uncini, specimen 199914 (2014).

Tables

TABLE 1. Length and observations on the reproductive biology of Branchiomma coheni found in Tampa Bay, Florida. Presence of character or detail indicated by +, absence indicated by -. All plates represented by a single specimen of Branchiomma coheni

Year	Block	Plate	Vial	Lenght (cm)	Molecular specimen	SERC collection Location	Oocytes Sperm Notes
2014	2240	16838	158629	3.7	+	Drawer 13 Box 103 B16	+ + No radioles, broken. Simultaneous hermaphrodite,
2014	2240	16838	199914	3.7	-	Drawer 13 Box 103 C2	+ - Female, only eggs present, no evidence of regeneration.
2014	2240	16829	158394	5	+	Drawer 13 Box 103 E16	+ + Simultaneous hermaphrodite. Smaller variation of stylodes
2012	2118	15009	168941	3.8	-	Drawer 11 Box 86 C11	+ + Simultaneous hermaphrodite. Smaller variation of stylodes