Page 96 - Invasive_Species_2013

Mediterranean invasive species factsheet

COMBJELLIES/CTENOPHORES

Reproduction Common name: Warty comb jelly

Comb row
identification

Scientific Name:
Mnemiopsis leidyi
Picture

Key identifying features
Brief history
This gelatinous planktonic organism (a ctenophore)
somewhat resembles a jellyfish. It is oval in shape,
laterally compressed, transparent and approximately Long oral lobes
7–12 cm in length and 2.5 cm in diameter. It has
8 ciliated bands or ‘combs’ (rows of small ‘plates’
made of tiny hair-like cilia) running the length of its
body and two large oral lobes on either side which
open wide when feeding. Four smaller lobes are Reproduction
situated underneath the oral lobes. Mnemiopsis leidyi has both male and female
reproductive organs and is able to fertilize itself. It
Field identification signs and habitat reproduces at a phenomenal rate: a large individual
This species can be found in the water column of can release as many as 12,000 eggs a day. Under
shallow estuaries, bays and coastal marine waters optimum temperature (15–30 °C) and nutrient
forming large aggregations. It is capable of producing conditions, eggs can hatch and develop into free-
swimming adults within 14 days.
bioluminescence, and the ciliated bands may glow
green at night. The animal is usually transparent or It also has the ability to regenerate from fragments
translucent. larger than one-quarter of the body.

Mnemiopsis leidyi. Photo: L. van Waltraven

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