Ligia oceanica
Ligia oceanica, the sea slater, common sea slater or sea roach, is a littoral woodlouse, living on rocky seashores of the european North Sea and Atlantic coastlines.
L. oceanica is oval, twice as long as broad and may reach up to in length, making it one of the largest oniscid isopods. Its colour may vary from grey to olive-green, and it has large compound eyes and long antennae, ⅔ as long as its body.
L. oceanica is found in temperate waters from Norway to the Mediterranean Sea, and from Cape Cod north to Maine. It is a common species, occurring wherever the substrate of the littoral zone is rocky, and is especially common in crevices and rock pools and under stones. It is a nocturnal omnivore, eating many kinds of seaweed, diatoms and debris, with a particular fondness for bladder wrack.
L. oceanica individuals live for 2–3 years and usually breed only once.Genome
The mitochondrial genome of L. oceanica was sequenced in 2006. It is a circular double-stranded DNA molecule, with a size of 15,289 base pairs. Although gene order is not conserved among isopods, L. oceanica shows a similarly derived gene order to Idotea balthica, compared to the arthropod ground pattern, but the positions of three tRNA genes differ in the two isopod species.
