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For the United States & Canada

Species Ligia oceanica - Sea Slater

Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Crustacea (Crustaceans)
Class Malacostraca (Malacostracans)
Superorder Peracarida (Peracarida (Amphipods and Isopods))
Order Isopoda (Isopods)
Suborder Oniscidea (Woodlice)
Infraorder Diplocheta
Family Ligiidae (Rock Slaters)
Genus Ligia
Species oceanica (Sea Slater)
Other Common Names
Common Sea Slater
Explanation of Names
Author of species is Linnaeus 1767
up to 30 mm
Oval shaped, dorso-ventrally flattened body that is twice as long as broad. The antennae are approximately two thirds the length of the body; at least 10 segments on antennal flagellum. Seven externally visible thoracic segments. Seven pairs of walking legs. Two large uropods project from the posterior margin of the telson, each with two long processes or rami. Very large and obvious black eyes. Body color is gray to olive.
native to w. Europe, adventive in NA (ne. US: ME-MA)(1)
rocky coasts under stones and in crevices
Life Cycle
Mature by one year of age, but in most cases breeding will not begin until the sea slater is at least two years old. Breeding takes place in spring and summer. Most individuals only breed once, and have a life span of around two and a half to three years.
Internet References
Fact sheets (from UK): ARKive, MarLIN
Works Cited
1.Checklist of the terrestrial isopods of the New World (Crustacea, Isopoda, Oniscidea)
Leistikow A., Wägele J.W. 1999. Rev. Bras. Zool. 16: 1-72.