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Publication

Risk assessment of non-indigenous marine invaders: a combined approach of morphological and molecular analysis allowed unambiguous identification of the comb jelly Mnemiopsis leidyi in the Belgian Part of the North Sea

Book Contribution - Chapter

Mnemiopsis leidyi is an invasive American species present for more than 2 decades in European waters. This species has reportedly influenced the collapse of stressed environments and commercial fish stocks. Some native species are morphologically very similar to M. leidyi, which hinders identification of this ctenophore in newly invaded areas. Risk assessment of non-indigenous marine invaders can only be successful if identification is unambiguous and a combination of morphological and molecular analysis can be of great assistance. For this purpose different fixatives have been tested and scored on their ability to preserve morphological features and to allow extraction of DNA with high concentration and purity. Fixated samples of M. leidyi were observed microscopically and the extracted DNA was tested with primers for the nuclear internally transcribed spacer (ITS) region and the mitochondrial cytochrome b (CYTB) and cytochrome oxidase I (COI) region. The results of the molecular analysis were furthermore used to prepare a species specific DNA probe and primers to allow identification of M. leidyi in fish stomachs. This makes it a useful method to study prey – predator relationships which in turn can help in a better management of this notorious invader.
Book: Book of abstracts - VLIZ Young Scientists' Day. VLIZ Special Publication 55