Skip to main content Skip to main navigation menu Skip to site footer
Type: Article
Published: 2026-03-17
Page range: 169-183
Abstract views: 32
PDF downloaded: 2

Unexpected record of Meadia roseni Mok, Lee & Chan, 1991 (Anguilliformes: Synaphobranchidae) from the Western Indian Ocean, with comments on its ontogenetic changes

Tanzania Fisheries Research Institute (TAFIRI); P.O. Box 9750 Dar Es Salaam; Tanzania.
National Research Foundation—South African Institute for Aquatic Biodiversity; Makhanda 6140; South Africa.
Oceanographic Institute of Moçambique (INOM); 389. Box 4603 Maputo - Moçambique.
National Research Foundation—South African Institute for Aquatic Biodiversity; Makhanda 6140; South Africa.
National Research Foundation—South African Institute for Aquatic Biodiversity; Makhanda 6140; South Africa.
Department of Vertebrate Zoology; National Museum of Natural History; Smithsonian Institution; Washington; D.C.; U.S.A.
Pisces Ilyophinae Tanzania taxonomy morphology COI R/V Dr. Fridtjof Nansen trawl surveys

Abstract

Two specimens of a rare eel of the genus Meadia (Synaphobranchidae, Ilyophinae) were trawled during a survey conducted by the research vessel Dr. Fridtjof Nansen off Tanzania in 2023. Detailed examination and comparison with the three known species of the genus revealed that both specimens belong to Meadia roseni Mok, Lee & Chan, 1991, a species previously thought to be restricted to Taiwan and Vietnam. These specimens represent the first record of this species from the Indian Ocean. Species identification is supported by a phylogenetic analysis of the COI barcoding region, which included a specimen of M. roseni from Taiwan. Description of both Tanzanian specimens, based on voucher material, is provided and accompanied by photographs of fresh specimens. Ontogenetic changes associated with growth are also discussed.

 

References

  1. Appleyard, S.A., Ward, R.D., Pogonoski, J.J., Graham, A., Last, P.R., Deagle, B.E., Holmes, B., Gomon, M.F., Hoese, D.F., Bray, D.J., Williams, A., Smith, P.J., McGrouther, M., Johnson, J.W. & Bawden, K. (2024) Australia’s marine fishes DNA barcode reference library for integrated taxonomy, metabarcoding & eDNA research. Scientific Data, 12 (1), 21. https://doi.org/10.1038/s41597-025-04375-4
  2. Böhlke, E.B. (1951) Meadia, a new genus for the West Pacific dysommid eel, Dysomma abyssale Kamohara. Stanford Ichthyological Bulletin, 4 (1), 6.
  3. Böhlke, E.B. (1989) Methods and terminology. In: Böhlke, E.B. (Ed.), Fishes of the Western North Atlantic. Memoirs of the Sears Foundation for Marine Research, 1 (Part 9), pp. 1–7. https://doi.org/10.2307/j.ctvbcd0dm.4
  4. Chang, C.-H., Shao, K.-T., Lin, H.-Y., Chiu, Y.-C., Lee, M.-Y., Liu, S.-H. & Lin, P.-L. (2017) DNA barcodes of the native ray-finned fishes in Taiwan. Molecular Ecology Resources, 17 (4), 796–805. https://doi.org/10.1111/1755-0998.12601
  5. Costa, F.O., Landi, M., Martins, R., Costa, M.H., Costa, M.E., Carneiro, M., Martins, M.J., Steinke, D. & Carvalho, G.R. (2012) A Ranking System for Reference Libraries of DNA Barcodes: Application to Marine Fish Species from Portugal. PLoS ONE, 7 (4), e35858. https://doi.org/10.1371/journal.pone.0035858
  6. Eudeline, R. (2022) Illustrated checklist of Anguilliformes (Pisces, Teleostei) of the lagoon of Mayotte (Western Indian Ocean) with 14 new records. Marine and Fishery Sciences, 35 (1), 123–161. https://doi.org/10.47193/mafis.3512022010103
  7. Fricke, R., Eschmeyer, W.N. & van der Laan, R. (2026) Eschmeyer’s Catalog of Fishes, electronic version (02 February 2026). California Academy of Sciences, San Francisco. Available from: http://research.calacademy.org/research/Ichthyology/Catalog/fishcatmain.asp (accessed 2 February 2026)
  8. Ho, H.-C. & Vo, Q.V. (2024) New record of the cutthroat eel, Meadia roseni (Actinopterygii: Anguilliformes: Synaphobranchidae), from Vietnam. Acta Ichthyologica et Piscatoria, 54, 209–212. https://doi.org/10.3897/aiep.54.122733
  9. Ivanova, N.V., Zemlak, T.S., Hanner, R.H. & Hebert, P.D.N. (2007) Universal primer cocktails for fish DNA barcoding. Molecular Ecology Notes, 7, 544–548. https://doi.org/10.1111/j.1471-8286.2007.01748.x
  10. Kamohara, T. (1938) On the offshore bottom-fishes of Prov. Tosa, Shikoku, Japan. Maruzen Kobushiki Kaisha, Tokyo, 86 pp.
  11. Katoh, K., Misawa, K., Kuma, K. & Miyata, T. (2002) MAFFT: A novel method for rapid multiple sequence alignment based on fast Fourier transform. Nucleic Acids Research, 30, 3059–3066. https://doi.org/10.1093/nar/gkf436
  12. Katoh, K. & Toh, H. (2008) Recent developments in the MAFFT multiple sequence alignment program. Briefings in Bioinformatics, 9, 286–298. https://doi.org/10.1093/bib/bbn013
  13. Kenchington, E.L., Baillie, S.M., Kenchington, T.J. & Bentzen, P. (2017) Barcoding Atlantic Canada’s mesopelagic and upper bathypelagic marine fishes. PLoS ONE, 12 (9), e0185173. https://doi.org/10.1371/journal.pone.0185173
  14. Kimura, M. (1980) A simple method for estimating evolutionary rate of base substitutions through comparative studies of nucleotide sequences. Journal of Molecular Evolution, 16, 111–120. https://doi.org/10.1007/BF01731581
  15. Mok, H.-K., Lee, C.-Y. & Chan, H.-J. (1991) Meadia roseni, a new synaphobranchid eel from the coast of Taiwan (Anguilloidea: Synaphobranchidae). Bulletin of Marine Science, 48 (1), 39–45.
  16. Quéro, J.-C. & Saldanha, L. (1995) Poissons anguilliformes de l'Ile de la Réunion (Océan Indien): description d'une nouvelle espèce. Cybium, 19 (1), 61–88.
  17. Robins, C.H. & Robins, C.R. (1976) New genera and species of dysommine and synaphobranchine eels (Synaphobranchidae) with an analysis of the Dysomminae. Proceedings of the Academy of Natural Sciences of Philadelphia, 127, 249–280.
  18. Robins, C.H. & Robins, C.R. (1989) Family Synaphobranchidae. In: Böhlke, E.B. (Ed.), Fishes of the Western North Atlantic. Memoir of the Sears Foundation for Marine Research. Memoir 1. Part 9. Vol. 1. Sears Foundation for Marine Research, Yale University, New Haven, Connecticut, pp. 207–253. https://doi.org/10.2307/j.ctvbcd0dm.12
  19. Saitou, N. & Nei, M. (1987) The neighbor-joining method: A new method for reconstructing phylogenetic trees. Molecular Biology and Evolution, 4, 406–425.
  20. Sulak, K.J. & Shcherbachev, Y.N. (1997) Zoogeography and systematics of six deep-living genera of synaphobranchid eels, with a key to taxa and description of two new species of Ilyophis. Bulletin of Marine Science, 60 (3), 1158–1194.
  21. Sunnucks, P. & Hales, D.F. (1996) Numerous transposed sequences of mitochondrial cytochrome oxidase I–II in aphids of the genus Sitobion (Hemiptera: Aphididae). Molecular Biology and Evolution, 13 (3), 510–524. https://doi.org/10.1093/oxfordjournals.molbev.a025612
  22. Tamura, K. & Nei, M. (1993) Estimation of the number of nucleotide substitutions in the control region of mitochondrial DNA in humans and chimpanzees. Molecular Biology and Evolution, 10, 512–526. https://doi.org/10.1093/oxfordjournals.molbev.a040023
  23. Tamura, K., Stecher, G. & Kumar, S. (2021) MEGA 11: Molecular Evolutionary Genetics Analysis Version 11. Molecular Biology and Evolution, 38 (7), 3022–3027. https://doi.org/10.1093/molbev/msab120
  24. Tighe, K.A. & Kodeeswaran, P. (2025) A new genus and species of ilyophine eel (Anguilliformes: Synaphobranchidae: Ilyophinae) from the Arabian Sea, western Indian Ocean. Zootaxa, 5722 (4), 555–569. https://doi.org/10.11646/zootaxa.5722.4.6
  25. Tighe, K.A., Smith, D.G., Merrett, N.R., Frable, B.W. & Zajonz, U. (2024) Redescription of the eel Ilyophis arx Robins, 1976 (Anguilliformes: Synaphobranchidae: Ilyophinae) with a description of a new species of Ilyophis, and a taxonomic synopsis of the Ilyophinae. Zootaxa, 5506 (1), 35–57. https://doi.org/10.11646/zootaxa.5506.1.2
  26. Vo, Q.V., Ho, H.-C., Dao, H.V. & Tran, H.H.T. (2021) A new arrowtooth eel of genus Meadia (Synaphobranchidae: Ilyophinae) from Vietnam, South China Sea. Zootaxa, 4952 (1), 181–191. https://doi.org/10.11646/zootaxa.4952.1.11
  27. Wang, Z.D., Guo, Y.S., Liu, X.M., Fan, Y.B. & Liu, C.W. (2012) DNA barcoding South China Sea fishes. Mitochondrial DNA, 23 (5), 405–410. https://doi.org/10.3109/19401736.2012.710204
  28. Ward, R.D., Zemlak, T.S., Innes, B.H., Last, P.R. & Hebert, P.D. (2005) DNA barcoding Australia's fish species. Philosophical Transactions of the Royal Society B Biological Science, 360 (1462), 1847–1857. https://doi.org/10.1098/rstb.2005.1716

How to Cite

Matiku, P., Bogorodsky, S.V., Samucidine, K., Matcher, G., Bills, R. & Tighe, K.A. (2026) Unexpected record of Meadia roseni Mok, Lee & Chan, 1991 (Anguilliformes: Synaphobranchidae) from the Western Indian Ocean, with comments on its ontogenetic changes. Zootaxa, 5777 (1), 169–183. https://doi.org/10.11646/zootaxa.5777.1.8