Ligia

Ligia
Ligia oceanica
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Subphylum:	Crustacea
Class:	Malacostraca
Order:	Isopoda
Family:	Ligiidae
Genus:	Ligia Fabricius, 1798
Type species
Ligia oceanica Linnaeus, 1767

Ligia is a genus of isopods, commonly known as rock lice or sea slaters. Most Ligia species live in tidal zone cliffs and rocky beaches, but there are several fully terrestrial species in high humidity environments.

Coastal Ligia exhibit a mixture of terrestrial and marine characteristics, drying out easily, needing moist air and proximity to water to retain water. While they have gills and can exchange gas under water, they only do so when escaping terrestrial predators or being dislodged by wave action. They do not move swiftly in the water and are open to marine predation. They are well adapted to rocky surfaces and avoid sand which opens them to terrestrial predation and desiccation.

Species separation is at times difficult because of sexual dimorphism. For example, males usually have longer and wider antennae than females, although this is often not the case. The male also tends to be larger but narrower, sometimes attributed to the female’s brood pouch.

The following is a list of all Ligia species contained in the bibliography of terrestrial isopods.

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Wikipedia