Ligia

Ligia
Ligia oceanica
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Malacostraca
Order:	Isopoda
Suborder:	Oniscidea
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, ^[1] in the family Ligiidae. ^{[2] [3]} Most Ligia species live in tidal zone cliffs and rocky beaches, but there are several fully terrestrial species which occur in high-humidity environments. ^[4]

Ecology

Coastal Ligia species exhibit a mixture of terrestrial and marine characteristics, drying out easily, needing moist air and proximity to water to retain water. ^[5] While they have gills and can exchange gas under water, they only do so when escaping terrestrial predators or being dislodged by wave action. ^[5] 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. ^[4]

Taxonomy

Authorities place this genus in the suborder Oniscidea based on morphology. ^[6] Phylogenetic analysis based on molecular data, however, suggest that Ligia is more closely related to the marine isopods in the suborders Valvifera and Sphaeromatidea than to the terrestrial woodlice in the suborder Oniscidea. ^{[7] [8] [9]}

Species

Species separation is at times difficult because of sexual dimorphism. For example, males usually have longer and wider antennae than females. ^[10] The males also tend to be larger but narrower, with the difference sometimes attributed to the female's brood pouch. ^[10] Complicating matters is the possible existence of cryptic species in the genus. ^[11]

This is a list of all Ligia species contained in A Bibliography of Terrestrial Isopods: ^{[12] [13]}

• Ligia australiensis – Australian slater, Australia, including Tasmania and Lord Howe Island
• Ligia baudiniana – east and west coasts of the Americas
• Ligia boninensis – Bonin Islands, Japan
• Ligia cajennensis – French Guiana
• Ligia cinerascens – Hokkaido and northern Honshu, Japan, and the Kuril Islands
• Ligia cursor – Chile
• Ligia curvata – Angola
• Ligia dante – Hawai'i Island (Hawaii) ^[14]
• Ligia dentipes – Andaman and Nicobar Islands, Indonesia
• Ligia dilatata – southern Africa (Namibia and South Africa)
• Ligia eleluensis – Maui, Hawaii ^[14]
• Ligia exotica – wharf roach, introduced around the world in subtropical and warm temperate coastlines
• Ligia ferrarai – Madagascar
• Ligia filicornis – Venezuela
• Ligia glabrata – Southern Africa (Namibia and South Africa)
• Ligia gracilipes – west coast of Africa, Senegal to northern Angola
• Ligia hachijoensis – Izu Islands, Japan
• Ligia hawaiensis – Kaua'i, Hawaii ^[14]
• Ligia honu – Hawaii Island, Hawaii ^[14]
• Ligia italica – coasts of the Black Sea, Mediterranean Sea, Atlantic in northern Africa downsouth to Cape Verde and Macaronesia Islands
• Ligia kamehameha – Hawaii Island, Hawaii ^[14]
• Ligia latissima – New Caledonia
• Ligia litigiosa – Chile and Peru and the Juan Fernández Islands
• Ligia malleata – Tanzania
• Ligia mauinuiensis – Maui Nui Islands and Oahu, Hawaii ^[14]
• Ligia miyakensis – Izu Islands, Japan
• Ligia natalensis – southeastern coast of South Africa from Knysna to Natal
• Ligia novizealandiae – New Zealand and Kermadec Island
• Ligia occidentalis – California, Baja California, British Columbia
• Ligia oceanica – Atlantic Coasts of Europe, coasts of western Baltic Sea and possibly introduced to the Atlantic Coast of North America
• Ligia pallasii – Pacific Coast of North America, the Aleutian Islands to Santa Cruz, California
• Ligia pallida – Christmas Island in Polynesia
• Ligia pele – Maui, Hawai'i ^[14]
• Ligia perkinsi – Kaua'i and O'ahu, Hawaiian Islands
• Ligia persica – Persian Gulf ^[13]
• Ligia philoscoides – southeastern Polynesia
• Ligia pigmentata – Red Sea, Persian Gulf and coast of Somalia
• Ligia platycephala – Venezuela, Guyana and Trinidad
• Ligia rolliensis – Oahu, Hawai'i ^[14]
• Ligia rugosa – southeastern Polynesia
• Ligia ryukyuensis – Japan
• Ligia saipanensi – Saipan Island, Micronesia
• Ligia simoni – Northern Venezuela and northern Colombia
• Ligia taiwanensis – Taiwan
• Ligia vitiensis – Sulawesi, Singapore, New Guinea, Melanesia, Polynesia, and possibly introduced to Somalia
• Ligia yamanishii – Tokyo
• Ligia yemenica – Gulf of Aden ^[13]

References

1. "Ligia Fabricius, 1798". www.gbif.org. Retrieved 2025-07-06.
2. "ITIS - Report: Ligia". itis.gov. Retrieved 2025-07-06.
3. "Ligia Fabricius, 1798 | COL". www.catalogueoflife.org. Retrieved 2025-07-06.
4. Luis A. Hurtado, Mariana Mateos & Carlos A. Santamaria (2010). "Phylogeography of supralittoral rocky intertidal Ligia isopods in the Pacific region from central California to central Mexico". PLoS ONE . 5 (7): e11633. Bibcode:2010PLoSO...511633H. doi: 10.1371/journal.pone.0011633 . PMC   2908127 . PMID   20657776.
5. Xu, Lele; Li, Yongqin; Liu, Yao; Mi, Haifeng; Jiang, Xiang; Sun, Yulin; Zhao, Haiyong; Chen, Daohai; Wang, Liyun (2021-03-30). "A comprehensive evaluation of the potential of semiterrestrial isopods, Ligia exotica, as a new animal food". Scientific Reports. 11 (1): 7213. Bibcode:2021NatSR..11.7213X. doi:10.1038/s41598-021-86561-z. ISSN   2045-2322. PMC   8009950 . PMID   33785800.
6. Wilson, George (2009-08-25). "The phylogenetic position of the Isopoda in the Peracarida (Crustacea: Malacostraca)". Arthropod Systematics & Phylogeny. 67 (2): 159–198. doi: 10.3897/asp.67.e31696 . ISSN   1864-8312.
7. Dimitriou, Andreas C.; Taiti, Stefano; Sfenthourakis, Spyros (6 December 2019). "Genetic evidence against monophyly of Oniscidea implies a need to revise scenarios for the origin of terrestrial isopods". Scientific Reports. 9 (1). Nature: 18508. Bibcode:2019NatSR...918508D. doi:10.1038/s41598-019-55071-4. PMC   6898597 . PMID   31811226.
8. Lins, Luana S. F.; Ho, Simon Y. W.; Lo, Nathan (15 October 2017). "An evolutionary timescale for terrestrial isopods and a lack of molecular support for the monophyly of Oniscidea (Crustacea: Isopoda)" . Organisms Diversity & Evolution. 17 (4). Springer: 813–820. Bibcode:2017ODivE..17..813L. doi:10.1007/s13127-017-0346-2. S2CID   6580830.
9. Gregory, Steve (2020). "Bye Bye Ligia" (PDF). British Myriapod and Isopod Group Newsletter. 40: 5–7.
10. Harold Gordon Jackson (1922). "A revision of the isopod genus Ligia (Fabricius)". Proceedings of the Zoological Society of London . 1922: 483–1276.
11. Santamaria, Carlos A.; Bluemel, Joanna K.; Bunbury, Nancy; Curran, Melinda (2017-10-06). "Cryptic biodiversity and phylogeographic patterns of Seychellois Ligia isopods". PeerJ. 5 e3894. doi: 10.7717/peerj.3894 . PMC   5633021 . PMID   29018626.
12. H. Schmalfuss & K. Wolf-Schwenninger (2004). "A bibliography of terrestrial isopods (Crustacea, Isopoda, Oniscidea)" (PDF). Stuttgarter Beiträge zur Naturkunde . 639: 1–120.
13. Khalaji-Pirbalouty, Valiallah; Wägele, Johann-Wolfgang (2010). "Two new species of Ligia Fabricius, 1798 (Crustacea: Isopoda: Ligiidae) from coasts of the Persian and Aden gulfs". Organisms Diversity & Evolution. 10 (2): 135–145. Bibcode:2010ODivE..10..135K. doi:10.1007/s13127-010-0003-5. S2CID   30197033.
14. Santamaria, Carlos A. (2019-08-15). "Molecular taxonomy of endemic coastal Ligia isopods from the Hawaiian Islands: re-description of L. hawaiensis and description of seven novel cryptic species". PeerJ. 7 e7531. doi: 10.7717/peerj.7531 . PMC   6698373 . PMID   31435494.

External links

• Data related to Ligia at Wikispecies