Forskalia edwardsii is one of the 175 described species within the phylum of cnidarians, belonging to the Hydrozoa class and to the order of siphonophores (Siphonophorae). It is an order of species very little studied, probably due to the fragility of their bodies, which may have hindered the capture of specimens for detailed study. It is a frequent species in all oceans (Atlantic, Indian, Pacific) and especially frequent in the Mediterranean Sea. It usually lives in open waters but always at shallow depths (up to 10 meters) where they remain drifting, dragged by the prevailing currents. After strong storms (often in late spring), it is common to observe Forskalia edwardsii specimens in areas closer to the coast.
The body of Forskalia edwardsii consists of a multitude of individuals (zooids) that make up the floating colony, which can reach up to 2 meters in total maximum length. The upper part of the colony, known as the pneumatophore, is a specialized structure that provides the hydrodynamic lift that allows the colony to maintain buoyancy. It is followed by several swimming bells and behind them we find emerging from a central cord the so called cormids. These are structures formed by a group of zooids specialized in specific tasks, which form a sub-colony within the main colony. Among the different functions of the different zooids are those that specialize in capturing food, those that are responsible for the reproduction of the colony and those that protect the colony from predators. These cormids have a reddish coloration and have a thin filament on their outermost part loaded with highly stinging cells with which they capture their prey. The cormids are arranged in several intertwined rows on the central stolon.
The feeding of Forskalia edwardsii is based mainly on the capture of small crustaceans present in the plankton with its stinging filaments.
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