The Rockpool Shrimp is a species in the order of Decapoda and thus belongs to the subphylum of the Crustacea.
Description
Palaemon elegans has an elongated, transparent body with dark brown to black streaks which are arranged annularly. Their legs have a bluish glow and the joints are yellow.
It reaches a maximum length of 63mm, although the specimens that I have found were not longer than 30mm.
Habitat and Distribution
The Rockpool Shrimp populate rocky or sandy ground, with algae growth, in tide pools. So it lives in very shallow water. When diving in the Canary Islands you can observe them rather less. But if you make a walk along the coast and observe the tide pools closely, you will find it quiet frequently!
Apart from the Canary Islands, Palaemon elegans is spread from the Baltic Sea, to the southwest of Norway, the Azores, the northeast Atlantic, the Mediterranean Sea, to the Black Sea. Perhaps even farther, but there are often confusion with close relatives.
Biology
The Rockpool Shrimp feeds on algae, detritus and other small creatures. They also appear to be very curious and / or show behaviour of cleaner shrimps. During my excursions through the tide pools, they sometimes crawled on my hands.
Their reproduction takes place from April to September, whereby the females breed their eggs up to twice a year. After fertilization the females carry the eggs with them until the larvae hatch. The larva runs through several stages of development until it becomes a shrimp.