Striped Green Sea Anemone

This is a smaller species, measuring approximately 3.5 centimeters in diameter across its tentacles and 3 centimeters in height. Its central column is green-gray to brown color and smooth. The column, which houses the gastro vascular central cavity extends from the mouth to the attached base called the pedal disc. It does not always have vertical stripes, which can be orange or white. There are 50 to 100 slender and tapered tentacles which are able to retract completely into the column. They are commonly transparent and can be gray or light green with white flecks (Christine 2001).

This species originated from the Pacific coast of Asia, but is currently found in the Northern Hemisphere. It has been found in Japan, the Gulf of Mexico (Verrill), Plymouth and Wells, Norfolk, England (R.B. Williams), Western Europe, the Mediterranean Sea, the Suez Canal, Malaysia (D. F. Dunn, California Academy of Sciences), and on the east and west coasts of North America (L. L. Minasian, Myers 1977, Stephenson 1935, Sassaman and Mangum 1970, Shick, J. H. Ting 1983, Uchida 1932, G. M. Watson, W. E. Zamer 1999). It has also been found in Hawaii and other sites of the Pacific Ocean. Recently it has appeared in Argentina and other localities of South America. Distribution away from Asia may have occurred by attachment to ship bottoms, oyster shipments, and seaweed. These anemones target ecosystems that are barren landscapes or with low species diversity.

Anemones, like all cnidarians, have nematocysts, which are stinging organelles used for defense and catching prey. Studies of nematocyst development on tentacle tips of this and several species reveals several different stages of tentacle morphology (Watson and Mariscal, Florida State University 1983). Comparisons to hydrozoans in terms of growth stages or bulb pulses of tentacle development are explained by growth of individual tentacles by widening or an increasing length of the column (Campbell 1980). The nematocysts are found on both catch tentacles and feeding tentacles. The catch tentacles used for aggression and capturing of prey have larger length and width than feeding tentacles, which aid in the capture of food. Feeding tentacles are displaced by catch tentacles during growth cycles, and migrate towards the central column.

While this sea anemone can reproduce sexually, it normally reproduces asexually by longitudinal fission. The asexual process is where a new polyp develops from a portion of the original polyp after pulling away (anemone splits in half). In many localities, there is little or no genetic variability between individual polyps as they are all clones of each other. This leads to a situation where apparently thriving populations can suddenly vanish from a locality. This happens because there is a lack of genetic variability among the population, and as the limits of tolerance of some parameter is approached, there is a sudden incidence of mortality among the whole population.