Mnemiopsis leidyi A Agassiz 1865

Mnemiopsis leidyi is the commonest ctenophore in the São Sebastião Channel.
It occurs all over the year, generally in shallow waters near the coastline. It is easily distinguished from other lobate ctenophores by the aboral origin of the lobes, near the apical organ, forming long furrows between lobes and the central portion of its body. The outer surface of the body is often covered by variable number of small warts.

Specimens reach about 110 mm in length.

The species is originally from the eastern coast of Americas. It was reported as an invader in the Black and Caspian seas, where it generated great environmental and economical impacts, adversely affecting fishing stocks by predation on fish eggs and larvae. Recently the species was reported also to the Baltic and North seas. It lives in coastal and estuarine waters, tolerating a wide range of salinity and temperature.

For further information on Mnemiopsis leidyi see:

· Mayer, A.G. (1912) Ctenophores of the Atlantic coast of North America. Carnegie Institution of Washington (Publ. 162), 58pp. [PDF 5.8Mb]

· Shiganova T.A. & Panov V.E. Mnemiopsis leidyi invasion in Mediterranean basin. Internet website. [Link]

· Dumont, H.; Shiganova T.A. & Niermann U. (2004) Aquatic invasions in the Black, Caspian, and Mediterranean seas. Kluwer Academic Publishers, Dordrecht, The Netherlands. 313p.

· Oliveira, O.M.P. & Migotto, A.E. (2006) Pelagic ctenophores from the São Sebastião Channel, southeastern Brazil. Zootaxa, 1183: 1-26. [PDF available under request]

· Oliveira, O.M.P. & Marques, A.C. (2007) Geographic distribution and predatory impact of the ctenophore Mnemiopsis leidyi: a potential threat to the fisheries and planktonic ecosystems from Brazilian coast? In: Pereira, M.J. et al. (eds.), Plankton Symposium IV Abstracts. BDUA Journal of Biology, 2: 252.  [PDF]

· Oliveira, O.M.P. (2007) The presence of the ctenophore Mnemiopsis leidyi in the Oslofjorden and considerations on the initial invasion pathways to the North and Baltic Seas. Aquatic Invasions, 2(3): 185-189. [PDF]