About SEASLUG.WORLD

SEASLUG.WORLD is a community-built sea slug database. Operated continuously since 2015, it welcomes contributions from anyone who has encountered a sea slug — divers, snorkellers, researchers, students.

What your submission grows

  • Your own catalogue — your observations accumulate on your My Page as a personal record of when, where, and what you saw
  • The site-wide guide — when others submit the same species, it builds up colour variation, distribution, and seasonality data for that taxon
  • Scientific databases — observation metadata is published as an open dataset on BISMaL / OBIS as a contribution to marine biodiversity research (see below)

Every submission is identified by the site owner before publication. As an aid during submission, the form shows an AI species-prediction assist (the site owner makes the final call).

  • Contributors: 615
  • Species: 2,112
  • Observation records (with photos): 50,380
  • Founder: Nobuhiko Kimoto

Dataset / citable URLs

Observation records from the site are also registered with external biodiversity databases as an open dataset. For academic citation, please use:

Suggested citation format (BISMaL's recommended form):

Kimoto, N. (2025) A photographically-vouchered global citizen science dataset of sea slugs (Mollusca: Heterobranchia) from the SEASLUG.WORLD platform since 2015. Available at https://doi.org/10.48518/00032. Accessed on yyyy-mm-dd.

Media appearances / photo provisions

Selected appearances of the site's photos in print and broadcast:

  • 2024 — Nishida K. Ecological Field Guide to Sea Slugs (Seibundo Shinkosha)
  • 4 June 2023 — Nippon TV The Tetsuwan DASH!!
  • 15 June 2020 — Sea Slugs: A Visual Field Guide (Revised Edition), Nature Watching Guidebook series (Seibundo Shinkosha)

Academic citations

Researchers have cited our species pages, observation records, or photographer names in peer-reviewed papers. We are typically not notified of such citations and the list below reflects only what we have happened to find ourselves. If you know of additional examples, please let us know.

Eponym

  • Hantazuia kimotoi Korshunova, Fletcher & Martynov, 2025 — a new genus and species named after the site's founder. Korshunova T., Fletcher K. & Martynov A. (2025). The endless forms are the most differentiated — how to disentangle the deep complexity of nudibranch classification. Zoological Journal of the Linnean Society 204(4): zlaf057.

Talks and writings by the site founder

  • 28 February 2021 — Kimoto N. "About SEASLUG.WORLD." Invited talk at the public lecture "Tales of Japanese sea slugs: from seven decades of regional surveys to today's research" hosted by the Osaka Bay Coastal Biology Research Group (co-hosted with the Osaka Museum of Natural History; held on Zoom).
  • 18 May 2025 — Mini-symposium "Vernacular names of molluscs" at the 2025 annual meeting of the Malacological Society of Japan.
    • Kimoto N. (operator of seaslug.world) — "Vernacular names of sea slugs: open issues"
    • Other speakers: Ueshima R. (Univ. Tokyo), Hasegawa K. (National Museum of Nature and Science), Senou H. (Kanagawa Prefectural Museum of Natural History)
  • September 2025 — Kimoto N. "Building and operating the website Sekai no Umiushi (SEASLUG.WORLD)." Umiushi-Tsushin, No. 128, pp. 6-7 (Research Institute of Marine Invertebrates).

Papers citing the site (chronological, newest first)

  • 2025 — Zhang S. & Wang J. Description of a new species of Pseudobornella Baba, 1932. ZooKeys 1241.
    • Cited as: Nobuhiko K (2017) Pseudobornella orientalis. https://en.seaslug.world/species/pseudobornella_orientalis [Accessed 25 April 2025]
    • In-text: "Known from Yellow Sea, China, and possibly also distributed in Japan (Kinoshita 2002; Nobuhiko 2017)."
  • 2024 — Paz-Sedano S., Moles J., Smirnoff D., Gosliner T.M. & Pola M. A combined phylogenetic strategy illuminates the evolution of Goniodorididae nudibranchs. Molecular Phylogenetics and Evolution 192: 107990.
    • N. Kimoto listed in the Acknowledgements.
  • 2022 — Paz-Sedano S., Smirnoff D., Candás M., Gosliner T.M. & Pola M. The genus Murphydoris Sigurdson, 1991 (Nudibranchia, Goniodorididae): with descriptions of four new species from the Indo-Pacific. Zoological Journal of the Linnean Society (doi: 10.1093/zoolinnean/zlac002).
    • Cited as: Kakegawa M. 2017/2018. Goniodoridella sp 12. In: Seaslug.world. Available at: https://en.seaslug.world/species/...
  • 2021 — Paz-Sedano S. & Pola M. An ocean yet to be discovered: increasing systematic knowledge of Indo-Pacific Okenia Menke, 1830 (Nudibranchia: Goniodorididae). Invertebrate Systematics 35: 797-825 (doi: 10.1071/IS20088).
    • Kakegawa, M. (2016). Okenia rhinorma Rudman, 2007. In 'Nudibranchs in the World'. Available at https://en.seaslug.world/species/okenia_rhinorma/4036
    • Kakegawa, M. (2017). Okenia echinata Baba, 1949. In 'Nudibranchs in the World'. Available at https://en.seaslug.world/species/okenia_echinata/7876
    • Kakegawa, M. (2020). Okenia echinata Baba, 1949. In 'Nudibranchs in the World'. Available at https://en.seaslug.world/species/okenia_echinata/19927
  • 2021 — Mehrotra R., Caballer Gutiérrez M.A., Scott C.M. et al. An updated inventory of sea slugs from Koh Tao, Thailand, with notes on their ecology and a dramatic biodiversity increase for Thai waters. ZooKeys 1042: 73-188 (doi: 10.3897/zookeys.1042.64474).
    • Cited as: SSW [SeaSlug World] (2017) SeaSlug World Colinatys sp. 1 – date 25/03/2017. https://en.seaslug.world/species/colinatys_sp._1
    • In-text: "records are limited to specimens from Hawaii (Oskars et al. 2015) and Japan (SSW [SeaSlug World] 2017)"
  • 2018 — Medrano S., Krug P.J., Gosliner T.M., Biju Kumar A. & Valdés Á. Systematics of Polybranchia Pease, 1860 (Mollusca: Gastropoda: Sacoglossa) based on molecular and morphological data. Zoological Journal of the Linnean Society 186: 76-115.
    • Cited as: Kimoto, 2017 in-text (multiple places), Available at: https://seaslug.world/species/...

Supporting the site

SEASLUG.WORLD is operated by an individual (Nobuhiko Kimoto). Beyond servers and domain costs, considerable time is invested every day in reviewing original descriptions and taxonomy literature, identifying species, writing, fieldwork, and contributing data to the BISMaL and OBIS biodiversity databases. Reader support helps keep the catalog growing.

For personal supporters (Premium membership, tips, Amazon gift cards, merchandise) please see "Support the Site". Corporate sponsors, publishers, and media partners please see the next section.

Non-monetary contributions are also welcome — photos and observation records directly enrich the site's content. We also welcome guest blog contributions — observation notes, field reports, taxonomic topics, and so on. If interested, please get in touch.

Photo use for academic publications

Photos hosted on SEASLUG.WORLD are copyrighted by their individual contributors. The site does not grant blanket reuse permission. If you would like to use a photo in a publication, please contact us — we will reach out to the contributor on your behalf and convey whether permission can be granted.

Contact

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