Skip to main content Skip to main navigation menu Skip to site footer
Responsive image
Issue: Vol. 5453 No. 4: 22 May 2024
Type: Article
Published: 2024-05-22
DOI: 10.11646/zootaxa.5453.4.1
Page range: 451-486
Abstract views: 62
PDF downloaded: 2

A morphological and molecular study of Ligia exotica Roux, 1828 (Crustacea: Isopoda: Ligiidae) from Japan, with descriptions of two new species

Osaka Museum of Natural History; Nagai Park; Higashi-Sumiyoshi; Osaka 546-0034 Japan
Health and Environmental Risk Division; National Institute for Environmental Studies; Tsukuba; Ibaraki 305-8506 Japan
Crustacea 16S rRNA appendix masculina Ligia shinjiensis Osaka Bay pereopod synonym taxonomy

Abstract

Ligia exotica Roux, 1828 was originally described based on specimens collected on a ship that came from Cayenne in French Guiana, and has been known to be widely distributed in the world. In Japan this species is the most common in Ligia, and two forms of L. exotica inhabit Osaka Bay, central Japan. To reveal the accurate scientific names of the two forms, we examined not only the detailed morphology but also 16S rRNA and NaK nucleotide sequences, together with L. exotica from another Japanese locality and the related species, L. shinjiensis Tsuge, 2008. As a result, three species, Ligia exotica, L. furcata sp. nov. and L. laticarpa sp. nov., are recognized in four localities, and L. shinjiensis is synonymized with L. exotica. Ligia exotica is characterized by the dentate lacinia mobilis on the right mandible and the appendix masculina lacking a projection. Ligia furcata and L. laticarpa are also characterized by the furcate propodus of the male pereopod 1 and the appendix masculina with an angular projection, and the swollen carpus of the male pereopod 1 and the appendix masculina with a rounded projection, respectively. The three species are distinguishable from one another mainly based on the shapes of pereopods 1–3 in both sexes and the appendix masculina of male. The 16S rRNA analysis confirms the results of the morphological study, and reveals that L. exotica and L. laticarpa also inhabit all over the world (e.g., East Asia, Southeast Asia, India, Africa, the Americas and Hawaii), and China and South Korea, respectively.

 

References

  1. Andersson, Å. (1960) South American terrestrial isopods in the collections of the Swedish State Museum of Natural History. Arkiv för Zoologi, Series 2, 12, 537–570.
  2. Barnard, K.H. (1932) Contribution to the crustacean fauna of South Africa. No. 11. Terrestrial Isopoda. Annales of the South African Museum, 30, 179–388.
  3. Boyko, C.B., Bruce, N.L., Hadfield, K.A., Merrin, K.L., Ota, Y., Poore, G.C.B. & Taiti, S. (Eds.) (2024) World Marine, Freshwater and Terrestrial Isopod Crustaceans database. Ligia Fabricius, 1798. Available from: https://www.marinespecies.org/aphia.php?p=taxdetails&id=146998 (accessed 18 March 2024)
  4. Brandt, I.F. (1833) Conspectus monographiæ crustaceorum oniscodorum Latreillii. Bulletin de la Société impériale des naturalistes de Moscou, 6, 171–193, pl. 4.
  5. Brian, A. & Dartevelle, E. (1949) Contribution à l’étude des Isopodes marins et fluviatiles du Congo. Annales du Musée du Congo Belge, C. Zoologie, Série III, III, 1, 77–208.
  6. Budde-Lund, G. (1885) Crustacea Isopoda Terrestria per Familias et Genera et Species, Descripta. Sumtibus Auctoris, Hauniae, 319 pp. https://doi.org/10.5962/bhl.title.109769
  7. Chen, G.-X. (1987) The description of two Ligia species. Chinese Journal of Zoology, 22 (2), 8–11. [in Chinese]
  8. Chilton, C. (1916) Fauna of the Chilka Lake. Some terrestrial Isopoda from the shore of the lake. Memoirs of the Indian Museum, 5, 461–482.
  9. Dana, J.D. (1853) Crustacea. Part II. United States Exploring Expedition during the Years 1838, 1839, 1840, 1841, 1842, under the Command of Charles Wilkes, U.S.N., 14, 689–1618. https://doi.org/10.5962/bhl.title.61409
  10. Dana, J.D. (1855) Crustacea. Atlas. United States Exploring Expedition during the Years 1838, 1839, 1840, 1841, 1842, under the Command of Charles Wilkes, U.S.N., 13/14, 1–27, pls 1–96. https://doi.org/10.5962/bhl.title.61409
  11. Darriba, D., Taboada, G.L., Doallo, R. & Posada, D. (2012) jModelTest 2: more models, new heuristics and parallel computing. Nature Methods, 9, 772. https://doi.org/10.1038/nmeth.2109
  12. Dollfus, A. (1893a) Notes de géographie zoologique. Sur la distribution du genre Ligia Fabr. La Feuille des Jeunes Naturalistes: Revue Mensuelle d'Histoire Naturelle, 24, 23–26.
  13. Dollfus, A. (1893b) Voyage de M. E. Simon au Venezuela (Décembre 1887–April 1888). 25e mémoire (1). Isopodes terrestres. Annales de la Société entomologique de France, 62, 339–346, pls 9–10.
  14. Dollfus, A. (1900) Crustacea Isopoda. Fauna Hawaiiensis, 2 (5), 521–526, pl. 20. https://doi.org/10.5962/bhl.title.4628
  15. Fabricius, J.C. (1798) Supplementum Entomologiae Systematicae. Proft et Storck, Hafniae, 572 + 53 pp. https://doi.org/10.5962/bhl.title.122153
  16. GBIF Secretariat (2024) Occurrence of Ligia exotica Roux, 1828. Available from: https://www.gbif.org/occurrence/search?taxon_key=5175654 (accessed 18 March 2024)
  17. Giambiagi de Calabrese, D. (1931) Oniscoideos del Río de la Plata (primera parte). Anales del Museo Nacional de Historia Natural “Bernardino Rivadavia”, 36, 417–429.
  18. Goswami, M.S., Pandya, P.J. & Kapuriya, A. (2023) First record of invasive isopod Ligia (Megaligia) exotica, Roux, 1828 (Crustacea: Isopoda: Oniscoidea) from Gujarat, western India: morphometric description and occurrence along Indian coast. Munis Entomology & Zoology, 18, 1407–1415.
  19. Goto, S. & Terao, A. (1911) Guide to dissection of an isopod Ligyda exotica. Zoological Magazine, 23, 270–277. [in Japanese] https://www.doi.org/10.34435/zm001180
  20. Green, A.J.A. (1962) Record of the occurrence in Australia of Ligia exotica Roux (Crustacea, Isopoda, Oniscoidea). Papers and Proceedings of the Royal Society of Tasmania, 96, 83–85. https://doi.org/10.26749/KDTC9182
  21. Hurtado, L.A., Mateos, M., Wang, C., Santamaria, C.A., Jung, J., Khalaji-Pirbalouty, V. & Kim, W. (2018) Out of Asia: mitochondrial evolutionary history of the globally introduced supralittoral isopod Ligia exotica. PeerJ, 6 (e4337), 1–25. https://doi.org/10.7717/peerj.4337
  22. Hütter, T., Ganser, M.H., Kocher, M., Halkic, M., Agatha, S. & Augsten, N. (2020) DeSignate: detecting signature characters in gene sequence alignments for taxon diagnoses. BMC Bioinformatics, 21, 1–9. https://doi.org/10.1186/s12859-020-3498-6
  23. International Commission on Zoological Nomenclature (1999) International Code of Zoological Nomenclature. Fourth Edition. Available from: https://www.iczn.org/the-code/the-code-online/ (accessed 18 March 2024)
  24. Itani, Y. (1999) Molecular phylogeography of the genus Ligia in the Japanese Islands. The Nature & Insects, 34 (2), 39–41. [in Japanese]
  25. Itani, Y. (2000a) Phylogeography of Japanese Ligia species (Isopoda: Crustacea) based on molecular phylogenetic analysis. PhD Thesis, Kyoto University, Kyoto, 91 pp. https://doi.org/10.11501/3167137
  26. Itani, Y. (2000b) Phylobiogeography of the genus Ligia (Crustacea: Isopoda) in Japan based on molecular phylogenetic analyses. Kaiyo Monthly, 32, 246–251. [in Japanese]
  27. Jackson, H.G. (1922) A review of the isopod genus Ligia (Fabricius). Proceedings of the Zoological Society of London, 1922, 683–703, 2 pls. https://doi.org/10.1111/j.1096-3642.1922.tb02164.x
  28. Jackson, H.G. (1927) A new subgenus of Ligia, with further observations on the genus. Annals and Magazine of Natural History, Series 9, 19, 129–136, pl. 2. https://doi.org/10.1080/00222932708633578
  29. Jackson, H.G. (1941) Check-list of the terrestrial and fresh-water Isopoda of Oceania. Smithsonian Miscellaneous Collections, 99 (8), 1–35.
  30. Jung, J., Eo, H.-S., Rho, H.S. & Kim, W. (2008) Two genetic lineages of sea slaters, Ligia (Crustacea: Isopoda) in South Korea: a population genetic approach. Molecules and Cells, 25, 523–530. https://doi.org/10.1016/S1016-8478(23)17613-8
  31. Kalyaanamoorthy, S., Minh, B.Q., Wong, T.K., von Haeseler, A. & Jermiin, L.S. (2017) ModelFinder: fast model selection for accurate phylogenetic estimates. Nature Methods, 14, 587–589. https://doi.org/10.1038/nmeth.4285
  32. Kang, S. & Jung, J. (2020) Discrepancies between mitochondrial DNA and AFLP genetic variation among lineages of sea slaters Ligia in the East Asian region. Animal Systematics, Evolution and Diversity, 36, 347–353. https://doi.org/10.5635/ASED.2020.36.4.061
  33. Kapli, P., Lutteropp, S., Zhang, J., Kobert, K., Pavlidis, P., Stamatakis, A. & Flouri, T. (2017) Multi-rate Poisson tree processes for single-locus species delimitation under maximum likelihood and Markov chain Monte Carlo. Bioinformatics, 33, 1630–1638. https://doi.org/10.1093/bioinformatics/btx025
  34. Kato, K. (1936) Secondary sexual character in some legs of the male Ligia exotica. Zoological Magazine, 48, 333–334. https://doi.org/10.34435/zm002437
  35. Katoh, K., Rozewicki, J. & Yamada, K.D. (2019) MAFFT online service: multiple sequence alignment, interactive sequence choice and visualization. Briefings in Bioinformatics, 20, 1160–1166. https://doi.org/10.1093/bib/bbx108
  36. Kersmaekers, M. & Verstraeten, C. (1990) Une nouvelle espèce du genre Ligia de Madagascar (Isopoda Oniscoidea). Bulletin des Recherches Agronomiques de Gembloux, 25, 263–270.
  37. Khalaji-Pirbalouty, V. & Wägele, J. (2010) Two new species of Ligia Fabricius, 1798 (Crustacea: Isopoda: Ligiidae) from coasts of the Persian and Aden gulfs. Organisms Diversity & Evolution, 10, 135–145. https://doi.org/10.1007/s13127-010-0003-5
  38. Kim, G., Kim, H., Mun, S., Choi, E.H., Nguyen, A.D. & Hwang, U.W. (2023) Molecular population genetics and phylogeographic studies of Ligia exotica and Ligia cinerascens in East Asia. Frontiers in Marine Science, 10 (1260171), 1–14. https://doi.org/10.3389/fmars.2023.1260171
  39. Latreille, P.A. (1810) Considérations générales sur l'ordre naturel des animaux composant les classes des crustacés, des arachnides, et des insectes; avec un tableau méthodique de leurs genres, disposés en familles. F. Schoell, Paris, 444 pp. https://doi.org/10.5962/bhl.title.34917
  40. Leach, W.E. (1814) Crustaceology. In: Brewster, D. (Ed.), The Edinburgh Encyclopædia. Vol. 7. William Blackwood, Edinburgh, pp. 383–437. https://doi.org/10.5962/bhl.title.30911
  41. Linnaeus, C. (1767) Classis V. Insecta. In: Systema naturæ per regna tria naturæ: secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Pars II. Laurentii Salvii, Holmiæ, pp. 533–1068. https://doi.org/10.5962/bhl.title.37256
  42. Miers, E.J. (1877) On a collection of Crustacea, Decapoda and Isopoda, chiefly from South America, with descriptions of new genera and species. Proceedings of the Zoological Society of London, 1877, 653–679, pls 66–69.
  43. Milne Edwards, M. (1840) Histoire naturelle des crustacés: comprenant l'anatomie, la physiologie et la classification de ces animaux. III. Librairie encyclopédique de Roret, Paris, 638 pp., 42 pls. https://doi.org/10.5962/bhl.title.16170
  44. Minh, B.Q., Schmidt, H.A., Chernomor, O., Schrempf, D., Woodhams, M.D., von Haeseler, A. & Lanfear, R. (2020) IQ-TREE 2: new models and efficient methods for phylogenetic inference in the genomic era. Molecular Biology and Evolution, 37, 1530–1534. https://doi.org/10.1093/molbev/msaa015
  45. Nicolet, H. (1849) Crustaceos. In: Gay, C. (Ed.), Historia fisica y politica de Chile segun documentos adquiridos en esta republica durante doce años de residencia en ella y publicada bajo los auspicios del supremo gobierno, Zoologia. Vol. 3. Paris and Museo de historia natural de Santiago, Santiago, pp. 115–318. https://doi.org/10.5962/bhl.title.16172
  46. Nicolet, H. (1854) Crustaceos. In: Gay, C. (Ed.), Atlas de la Historia fisica y politica de Chile. Vol. 2. Paris and Museo de historia natural de Santiago, Santiago, pls crustaceos 1–4. https://doi.org/10.5962/bhl.title.16172
  47. Nunomura, N. (1975) Marine Isopoda from the rocky shore of Osaka Bay, middle Japan (1). Bulletin of the Osaka Museum of Natural History, 29, 15–35.
  48. Nunomura, N. (1979) Ligia boninensis, a new isopod crustacean from Haha-jima, Bonin Islands, Japan. Bulletin of the Toyama Science Museum, 1, 37–40.
  49. Nunomura, N. (1983) Studies on the terrestrial isopod crustaceans in Japan. I. Taxonomy of the families Ligiidae, Trichoniscidae and Olberinidae. Bulletin of the Toyama Science Museum, 5, 23–68.
  50. Nunomura, N. (1990) Studies on the terrestrial isopod crustaceans in Japan. V. Taxonomy of the families Armadillidiidae, Armadillidae and Tylidae, with taxonomic supplements to some other families. Bulletin of the Toyama Science Museum, 13, 1–58.
  51. Nunomura, N. (1999) Sea shore isopod crustaceans collected from Izu Islands, middle Japan. Bulletin of the Toyama Science Museum, 22, 7–38.
  52. Nunomura, N. (2009) Terrestrial isopod crustaceans from Daito Islands, southern Japan. Bulletin of the Toyama Science Museum, 32, 75–87.
  53. Nunomura, N. & Shimomura, M. (2017a) Isopoda from Japan (47) Suborder Oniscidae. Aquabiology, 39, 506–511. [in Japanese]
  54. Nunomura, N. & Shimomura, M. (2017b) Isopoda from Japan (48) Suborder Oniscidae – Family Ligiidae. Aquabiology, 39, 643–646. [in Japanese]
  55. Nunomura, N., Horiguchi, H., Sasaki, T., Hironaka, M. & Hariyama, T. (2011) A new species of the genus Ligia (Crustacea: Isopoda: Ligiidae) from steep streams of Chichijima and Anijima Islands of the Ogasawara Islands. Bulletin of the Toyama Science Museum, 34, 73–79.
  56. Palumbi, S.R. (1996) Nucleic acids II: the polymerase chain reaction. In: Hillis, D.M., Moritz, C. & Mable, B.K. (Eds), Molecular Systematics. Second Edition. Sinauer Associates, Sunderland, pp. 205–247.
  57. Perty, M. (1834) Delectus animalium articulatorum, quae in itinere per Brasiliam annis MDCCCXVII–MDCCCXX jussu et auspiciis Maximiliani Josephi I. Bavariae regis augustissimi peracto. Impensis Editoris, Monachii, 224 pp., 40 pls. https://doi.org/10.5962/bhl.title.158694
  58. Puillandre, N., Brouillet, S. & Achaz, G. (2021) ASAP: assemble species by automatic partitioning. Molecular Ecology Resources, 21, 609–620. https://doi.org/10.1111/1755-0998.13281
  59. Rafinesque, C.S. (1815) Analyse de la nature ou Tableau de l'univers et des corps organisés. Palerme, 224 pp. https://doi.org/10.5962/bhl.title.106607
  60. Reca, A.R. (1972) Oniscoideos argentinos. II. Tres especies de isopodos terrestres de la costa maritima bonaerense (Crustacea, Isopoda). Physis, 31, 405–410.
  61. Richardson, H. (1899) Key to the isopods of the Pacific coast of North America, with descriptions of twenty-two new species. Proceedings of the United States National Museum, 21, 815–869. https://doi.org/10.5479/si.00963801.21-1175.815
  62. Richardson, H. (1901) Key to the isopods of the Atlantic coast of North America with descriptions of new and little known species. Proceedings of the United States National Museum, 23, 493–579. https://doi.org/10.5479/si.00963801.23-1222.493
  63. Richardson, H. (1902) The marine and terrestrial isopods of the Bermudas, with descriptions of new genera and species. Transactions of the Connecticut Academy of Arts and Sciences, 11, 277–310, pls 37–40.
  64. Richardson, H. (1904) Contributions to the natural history of the Isopoda. Proceedings of the United States National Museum, 27, 1–89 + 657–681. https://doi.org/10.5479/si.00963801.27-1350.113 https://doi.org/10.5479/si.00963801.27-1369.657
  65. Richardson, H. (1905) A monograph on the isopods of North America. Bulletin of the United States National Museum, 54, 1–727. https://doi.org/10.5479/si.03629236.54.i
  66. Richardson, H. (1909) Isopods collected in the Northwest Pacific by the U. S. Bureau of Fisheries streamer “Albatross” in 1906. Proceedings of the United States National Museum, 37, 75–129. https://doi.org/10.5479/si.00963801.37-1701.75
  67. Roman, M.-L. (1977) Les Oniscoidea halophiles de Madagascar (Isopoda, Oniscoidea). Beaufortia, 26, 107–152.
  68. Ronquist, F., Teslenko, M., van der Mark, P., Ayres, D.L., Darling, A., Höhna, S., Larget, B., Liu, L., Suchard, M.A. & Huelsenbeck, J.P. (2012) MrBayes 3.2: efficient Bayesian phylogenetic inference and model choice across a large model space. Systematic Biology, 61, 539–542. https://doi.org/10.1093/sysbio/sys029
  69. Roux, P. (1828) Crustacés de la Méditerranée et de son Littoral, Décrits et Lithographiés. Chez Levrault, Paris, 174 pp. (unnumbered), 45 pls. https://doi.org/10.5962/bhl.title.8729
  70. Santamaria, C.A., Mateos, M. & Hurtado, L.A. (2014) Diversification at the narrow sea-land interface in the Caribbean: phylogeography of endemic supralittoral Ligia isopods. Frontiers in Ecology and Evolution, 2 (42), 1–15. https://doi.org/10.3389/fevo.2014.00042
  71. Santamaria, C.A., Bischoff III, E.T., Aye, M., Phillips, K.W. & Overmeyer, V. (2017) First record of the Ligia baudiniana species complex in the American Gulf of Mexico coastline, as confirmed by morphological and molecular approaches. F1000Research, 6 (1602), 1–11. https://doi.org/10.12688/f1000research.12459.1
  72. Santamaria, C.A., Larson, A.J., Ambrosio, L.J., La Luz, A.M. & Rankin, K.W. (2022) First report of the introduced isopod Ligia exotica Roux, 1828 in rocky intertidal habitats of Midway Atoll, Papahānaumokuākea Marine National Monument as confirmed by morphological and molecular approaches. BioInvasions Records, 11, 983–990. https://doi.org/10.3391/bir.2022.11.4.16
  73. Santamaria, C.A., Mateos, M., Taiti, S., DeWitt, T.J. & Hurtado, L.A. (2013) A complex evolutionary history in a remote archipelago: Phylogeography and morphometrics of the Hawaiian endemic Ligia isopods. Plos One, 8 (12), e85199. https://doi.org/10.1371/journal.pone.0085199
  74. Santucci, R. (1937) Ricerche sulla fauna del Mar Rosso. Bollettino del Musei e Laboratorî di Zoologia e Anatomia Comparata della R. Universita’ di Genova, 17 (95), 1–10.
  75. Schmarfuss, H. & Ferrara, F. (1978) Terrestrial isopods from West Africa. Part 2: Families Tylidae, Ligiidae, Trichoniscidae, Styloniscidae, Rhyscotidae, Halophilosciidae, Phylosciidae, Platyarthridae, Trachelipidae, Porcellionidae, Armadillidiidae. Monitore Zoologico Italiano, Nuova Serie, Supplemento 11, 15–97. https://doi.org/10.1080/03749444.1978.10736575
  76. Schultz, G.A. (1974) Terrestrial isopod crustaceans (Oniscoidea) mainly from the West Indies and adjacent regions. 1. Tylos and Ligia. Studies on the Fauna on Curaçao and other Caribbean Islands, 45, 162–173.
  77. Schultz, G.A. & Johnson, C. (1984) Terrestrial isopod crustaceans from Florida (Oniscoidea). Tylidae, Ligiidae, Halophilosciidae, Philosciidae, and Rhyscotidae. Journal of Crustacean Biology, 4, 154–171. https://doi.org/10.2307/1547904
  78. Taiti, S., Ferrara, F. & Kwon, D.H. (1992) Terrestrial Isopoda from the Togian Islands, Sulawesi, Indonesia. Invertebrate Taxonomy, 6, 787–842. https://doi.org/10.1071/IT9920787
  79. Taiti, S., Arnedo, M.A., Lew, S.E. & Roderick, G.K. (2003) Evolution of terrestriality in Hawaiian species of the genus Ligia (Isopoda, Oniscidea). In: Sfenthourakis, S., De Araujo, P.B., Hornung, E., Schmalfuss, H., Taiti, S. & Szlavecz, K. (Eds.), The Biology of Terrestrial Isopods. V. Proceedings of the 5th International Symposium on the Biology of Terrestrial Isopods. Crustaceana Monographs 2. Brill, Leiden, pp. 85–102. https://doi.org/10.1163/9789047412854_010
  80. Tsang, L.M., Ma, K.Y., Ahyong, S.T., Chan, T.Y. & Chu, K.H. (2008) Phylogeny of Decapoda using two nuclear protein-coding genes: origin and evolution of the Reptantia. Molecular Phylogenetics and Evolution, 48, 359–368. https://doi.org/10.1016/j.ympev.2008.04.009
  81. Tsuge, M. (2008) A new species of the genus Ligia (Crustacea: Isopoda: Ligiidae) from the Lake Shinji (Shimane Prefecture), western Japan. Bulletin of the Toyama Science Museum, 31, 51–57.
  82. Vandel, A. (1960) Faune de France. Vol. 64. Isopodes Terrestres. Première Partie. Paul Lechevalier, Paris, 416 pp.
  83. Van Name, W.G. (1920) Isopods collected by the American Museum Congo Expedition. Bulletin of the American Museum of Natural History, 43, 41–108.
  84. Van Name, W.G. (1936) The American land and fresh-water isopod Crustacea. Bulletin of the American Museum of Natural History, 71, 1–535.
  85. Verhoeff, K.W. (1926) Isopoda terrestria von Neu-Caledonien und den Loyalty-Inseln. In: Sarasin, F. & Roux, J. (Eds.), Nova Caledonia. Forschungen in Neu-Caledonien und auf den Loyalty-Inseln. Recherches scientifiques en Nouvelle-Calédonie et aux Iles Loyalty. A. Zoologie. Vol. 4. C.W. Kreidel’s Verlag, Berlin, pp. 243–366. https://doi.org/10.5962/bhl.title.6790
  86. Verhoeff, K.W. (1928) Über einige Isopoden der zoologischen Staatssammlung in München. 38. Isopoden-Aufsatz. Zoologischer Anzeiger, 76, 25–36 + 113–123.
  87. Wada, T. (2012) First record of Ligia cinerascens (Isopoda: Ligiidae) and Cyclograpsus pumilio (Decapoda: Varunidae) from Shikoku, with note on cobble beach of Tokushima Prefecture. Bulletin of the Tokushima Prefectural Museum, 22, 69–78. [in Japanese]
  88. Wetzer, R. (2001) Hierarchical analysis of mtDNA variation and the use of mtDNA for isopod (Crustacea: Peracarida: Isopoda) systematics. Contributions to Zoology, 70, 23–39. https://doi.org/10.1163/18759866-07001002
  89. Wilson, G.D.F. (1991) Functional morphology and evolution of isopod genitalia. In: Bauer, R.T. & Martin, J.W. (Eds.), Crustacean Sexual Biology. Columbia University Press, New York, pp. 228–245.
  90. https://doi.org/10.7312/baue90796
  91. Yamanishi, R. (2011) Morphological characters of Ligia cinerascens Budde-Lund, 1885 (Crustacea: Isopoda: Ligiidae) newly recorded from Osaka Bay, the Inland Sea of Japan, compared with those of L. cinerascens from Hokkaido and of L. exotica Roux, 1828 from Osaka Bay. Bulletin of the Osaka Museum of Natural History, 65, 1–8.
  92. Yamanishi, R. (2021) Two forms of Ligia exotica Roux, 1828 (Isopoda: Ligiidae) in Osaka Bay, central Japan. Nanki Seibutsu, 63, 164–168. [in Japanese]
  93. Yin, J., Pan, D., He, C., Wang, A. & Yan, J. (2013) Morphological and molecular data confirm species assignment and dispersal of the genus Ligia (Crustacea: Isopoda: Ligiidae) along northeastern coastal China and East Asia. Zoological Journal of the Linnean Society, 169, 362–376. https://doi.org/10.1111/zoj.12068
  94. Yu, G., Smith, D.K., Zhu, H., Guan, Y. & Lam, T.T.Y. (2017) GGTREE: an R package for visualization and annotation of phylogenetic trees with their covariates and other associated data. Methods in Ecology and Evolution, 8, 28–36. https://doi.org/10.1111/2041-210X.12628
  95. Zhang, J., Kapli, P., Pavlidis, P. & Stamatakis, A. (2013) A general species delimitation method with applications to phylogenetic placements. Bioinformatics, 29, 2869–2876. https://doi.org/10.1093/bioinformatics/btt499