Beroe ovata, BRUGUIERE, 1789

Shiganova, Tamara A. & Abyzova, Galina A., 2022, Revision of Beroidae (Ctenophora) in the southern seas of Europe: systematics and distribution based on genetics and morphology, Zoological Journal of the Linnean Society 194, pp. 297-322 : 304-305

BEROE OVATA BRUGUIÈRE, 1789

Synonyms:

Beroe ovata Eschscholtz, 1829 ( Chun, 1880) .

Beroe ovata Bosc, 1802 ( Harbison et al., 1978).

Beroe ovata Chamisso & Eysenhardt, 1821 ( Mayer, 1912) (see for complete synonyms until 1912).

Beroe ovata Moser, 1903, 1910 .

Beroe clarkii Mayer, 1900 .

Beroe ‘ ovata ’ Eschscholtz, 1829 ( Mills et al., 1996).

Beroe ovata Mayer 1912 ( Seravin et al., 2002).

Beroe ovata sensu Mayer 1912 ( Bayha et al., 2004).

Beroe ovata has a wide, mitre-shaped flattened body, extended laterally in the voluminous stomodaeum ( Fig. 3A, B ). The lateral compression of the Beroe ovata body is remarkable, being more than three times flattened in the paragastral plane ( Fig. 3B ). It does not have an infundibular canal. The aboral end is rounded ( Fig. 3C ), while the oral end is almost straight and wider than the body width in adult individuals, which is characteristic only for B. ovata . Adult length is 50–160 mm ( Fig. 3A, B ), the length to width ratio (l/w) equals 1.1–1.2 ( Seravin et al., 2002; Shiganova & Malej, 2009). The meridional canals lie under eight rows of ciliary combs, which extend about three-quarters of the distance from the apical sense organ towards the mouth. Side branches (diverticulae) may be placed in connection to one another by means of an anastomosing network in the body ( Fig. 3C, D ) and, in addition, establishing a circle of an oral canal system. Like all species of genus Beroe , B. ovata has a wide-flaring mouth and large stomodaeum with powerful macrocilia on the walls near the mouth, three teeth with the middle tooth larger. Teeth help the ctenophore to capture whole prey or to bite part of prey ( Tamm & Tamm, 1993). The polar plate surrounding the sense organ at the aboral pole and is not fringed with a row of branched papillae ( Fig. 3D ). Beroe ovata is pink, while the largest adults are more intensely tinged brown and the plates are bioluminescent green.

Geographical distribution: Beroe ovata is the only species of Beroe that became an invasive, being introduced with ballast water into European waters. Consequently, besides the native regions, now its habitats include established populations in the recipient areas.

Native areas include: in Southern America – western coasts of the Atlantic Ocean from Colombia to Argentina (10°N to 42°S) ( Domaneschi, 1976; Mianzan, 1986, 1999; Genzano & Zamponi, 1993; Oliveira & Migotto, 2006; Oliveira et al., 2007; Nogueira Jr., 2012; Nogueira Jr. et al., 2015); and in Northern America – Narragansett Bay, Rhode Island; Chesapeake Bay, Maryland (only in high salinity waters); Biscayne Bay, Florida, coastal waters along the Gulf of Mexico ( Kremer, 1994).

As a non-native species, B. ovata has been reported in the Black Sea, the Sea of Azov, the Caspian Sea, the Sea of Marmara, the Aegean Sea, the Levantine Sea and in Danish waters (Great Belt), where in most cases it is able to control populations of the harmful invasive ctenophore M. leidyi ( Konsulov & Kamburska, 1998; Shiganova et al., 2000, 2001, 2007, 2014a, b; Seravin et al., 2002; Finenko et al., 2003; Isinibilir et al., 2004; Mirsoyan et al., 2006; Shiganova & Malej, 2009; Galil et al., 2011; Badreddine et al., 2020; Mamish et al., 2020; Roohi et al., 2020). Recently, it was also found in the Indian Ocean off the Kollam Coast, Kerala ( India) in the Arabian Sea (09°0.3279’N, 76°23.4594’E) (Haripraved et al., pers. comm.).

Habitat: Euryhaline and neritic coastal and estuarine warm waters ( Mianzan, 1986; Kremer, 1994; Oliveira & Migotto 2006).

Figures

Figure 3. Beroe ovata from the Black Sea. A, general view: PC – paragastal canal; STC –subtetacular meridional canal; SC – subsugital canal; a – anastomoses; d – diverticular. B, oral view of the body: M – mouth; MA – macrocilia. C, aboral part of body: A – aboral pole; I – infundibulum. D, part of body with canals: a – anastamoses, d – diverticular (photos by T. Shiganova).