ABOUT JSC
What is Japan Spider Catalog?
Japan Spider Catalog (JSC) is a database website that brings together a checklist, distribution records, and images of spiders from Japan.
JSC succeeds Japanese Spiders (CD-ROM), created by Akira Shinkai and colleagues. The JSC management group maintains it to keep the information up to date and carry it forward in a more accessible form.
Show table of contents
01
What you can do with JSC
Explore distributions
Search literature-based distribution records by combining family, genus, species, prefecture, island, author, reference, publication year, record category, and other criteria.
Compare images
Filter images by taxonomic, distribution, and image information, and compare them with a live spider or specimen at hand.
Download data
Download filtered records, species lists, author lists, and reference lists as CSV files, or save a distribution map as an image.
02
How to use JSC
Distribution page
View a distribution map
- Select a family, genus, or species, and optionally prefectures, islands, authors, or references.
- Specify publication years and record categories when needed.
- Area selection includes records assigned to prefectural mainland polygons touched by the selected area and records from islands whose representative points fall inside it. Records with an unknown island are included when the selected area touches the corresponding prefectural mainland polygon. If other criteria, such as a taxon, are active, only records matching those criteria are shown.
- Click a prefectural mainland polygon or an island point to open a summary. Choose View details to inspect the reference, record category, record accuracy, and notes.
- Use the download button at the upper right of the map to save the current map view as an image.
Image page
View images
- Narrow the results with the all-fields search or filters for family, genus, species, region, and image information.
- Under Maximum images, choose a taxonomic rank and a number to show only representative images.
- Adjust image size and labels, then switch among Grid, Details, and Trait table views.
- Click a thumbnail to view detailed information about the image.
JSC also works on smartphones
On a narrow screen, open and close the filters while viewing maps or images. Use Distribution and Images at the top to switch between the main pages.
03
Notes for interpreting the data
Scope of records
The JSC management group is currently redefining which records fall within the scope of inclusion, and the policy described below has not yet been finalized.
For new records registered from August 2026 onward, the policy is, in principle, to include records with clear collection data: who collected the specimen, when, and where. However, records based on taxonomic description papers and records accompanied by images showing features sufficient for species identification, even when the specimen has not been preserved, are planned for exceptional inclusion.
By contrast, records based solely on web pages whose contents may become impossible to re-examine because of broken links, and newspaper articles or similar sources for which the collector, determiner, or basis of the information cannot be adequately verified, may be excluded. Records of juveniles or individuals with an unknown life stage may also be excluded when there are concerns about the certainty of their identification.
Some species, however, have conventionally been recorded by confirming their webs or nests, while others have distinctive diagnostic features and are unlikely to be misidentified. We are therefore considering selecting species that could be included under specified conditions without adult specimens and compiling a list of them.
For some alien species and public-health pests, it may be difficult years later to trace individual historical cases—when and where they were found or confirmed, and which government agency responded or issued an announcement—from primary government sources. In such cases, contemporary newspaper articles or similar sources reporting those government announcements may qualify for inclusion after the provenance and content of the information have been assessed individually.
Applying the new policy retroactively to inherited historical materials could exclude more previously included records than necessary. Rather than excluding all past records uniformly, we are considering ways to retain the information while clarifying its status, such as displaying it separately as reference records.
We plan to seek opinions on the new policy at the Arachnological Society of Japan meeting at the end of August and reflect that feedback in the final policy.
Distribution records and record counts
Within a single reference, JSC combines records that have the same taxon, prefecture, island, and record category into one record. When the same distribution information is cited by a later publication, however, it may be stored as a separate record for each reference. Record counts therefore do not equal the actual numbers of collecting events, localities, or individuals.
Record categories
- Original
- A record for which the reference is judged to be the original source
- Cited
- A record cited from an earlier reference
- Unverified
- A record whose reference has not been checked, so its status as original or cited cannot be determined
- Unknown
- A record whose reference has been checked but for which it is difficult to determine whether it is original or cited
Outlying-island data and map points
Prefecture and island are managed as separate fields. Island unknown (reference checked) means that the reference was checked but the island could not be identified. Island unknown (reference not checked) means that the original reference has not been checked and the island cannot be identified.
Individual distribution records currently do not contain latitude and longitude for the actual collection locality. Points on the map represent islands and are not actual collection localities.
Record accuracy
Record accuracy reflects the references and taxonomic knowledge reviewed to date. JSC does not guarantee that identifications are correct, including records classified as "Normal". Not every questionable record has necessarily been classified as "Needs verification / misidentification", and assessments may change following taxonomic re-examination.
Order of references
The reference list is ordered by author name, publication year, and order of entry to approximate a conventional bibliography. Romanized author names are used for sorting in Japanese; English author names are used in other languages. References are placed at the end when the romanized author name is unknown.
04
Tutorials
Narrow down candidate species for a spider
- On the image page, specify what you know, such as family or genus, sex, life stage, general appearance, or genitalia.
- Compare candidate images and look for similar taxa.
- Move to the distribution page and check for known records in prefectures or islands near where the spider was collected.
- After narrowing the candidates, check diagnostic characters in published sources such as identification guides, original descriptions, and taxonomic revisions.
Use JSC images to obtain an initial idea of possible identifications. Genital images are included, but JSC is not an identification guide that explains how to distinguish species. Some species cannot be identified from the images currently recorded in JSC alone.
Explore a distribution
- Select a taxon on the distribution page and review records from the prefecture or island of interest and nearby areas.
- Use the map, species list, and reference list to identify recorded areas and the supporting literature.
- Also review records with an unknown island and records marked Needs verification / misidentification.
- When necessary, consult the original publication to investigate name changes, synonyms, misidentifications, and locality wording.
The absence of a record in JSC alone cannot establish a first prefectural or island record. Island records in particular are still being reorganized from Japanese Spiders (CD-ROM), and unverified records remain.
05
Terms of data use
Data obtained from JSC may be used for research, education, commercial purposes, and redistribution. When using the data, cite JSC in the specified format below.
You may modify the data, but you must state that it has been modified and must not present the modified content in a way that could be mistaken for official JSC data. These terms do not apply to material owned by third parties, including photographs and map boundary data.
Photographs
Rights to photographs belong to each photographer or rights holder, not to the JSC management group. Follow the license shown for each image. When the license is Unknown, permission to reproduce or modify the image has not been granted. Contact the photographer or rights holder if you wish to use it. Creative Commons licenses will gradually be assigned to images in the future.
Administrative boundaries on distribution maps
Distribution maps use processed National Land Numerical Information: Administrative Area Data, nationwide edition for 2019, Product Specification version 2.3, provided by Japan's Ministry of Land, Infrastructure, Transport and Tourism. When reproducing or modifying a distribution map, follow the terms of use for the National Land Numerical Information and identify both the source and the fact that it was processed.
Administrative Area Data (National Land Numerical Information Download Site) Terms of use for National Land Numerical Information
Source: Created by processing the 2019 National Land Numerical Information (Administrative Area Data) provided by Japan's Ministry of Land, Infrastructure, Transport and Tourism.
Disclaimer
JSC strives to keep its information accurate and up to date but does not guarantee completeness or accuracy. The JSC management group accepts no liability for losses arising from use of the site or data.
06
How to cite JSC
When using JSC, cite it in the following format. The version and access date are updated automatically.
Japan Spider Catalog. (2026). Japan Spider Catalog, ver. 読み込み中. https://japan-spider-catalog.pages.dev/ (accessed ).
07
History
1999–2004
Turning a dream into reality
In issue 77 of Kishidaia, published in 1999, Akira Shinkai proposed creating a complete list of Japanese spiders, prefectural bibliographies of spider literature, and prefectural spider lists in an article titled 夢 (=dream). The complete species list was published by Akio Tanikawa in 2000, and the prefectural bibliography by Akira Shinkai in 2001. The biological distribution mapping program SPMAP, developed by Akihisa Andoh, was subsequently introduced, and Prefectural Distribution Maps of Japanese Spiders CD Ver.2004 was released in 2004.
2004–2024
Development into Japanese Spiders (CD-ROM)
Live and specimen photographs by Akio Tanikawa and クモ生理生態事典 [Encyclopedia of Spider Physiology and Ecology] by Hiroyoshi Ikeda, among other resources, were integrated to create Japanese Spiders (CD-ROM). The final ver.2024 contains distribution maps for 1,699 species whose references were checked and photographs of 1,023 species.
2024
Launch of the former Japan Spider Catalog
To address issues such as operating-environment compatibility, transfer of information, and continued updating, the former JSC was created and released using a cloud-based dashboard, chiefly by young researchers and students affiliated with Bulletin of Tokyo Spider Study Group. It enabled dynamic switching among the checklist of Japanese spiders, distribution records by prefecture and island, references, and update history.
2026
Transition to the current web application
JSC moved to a client-side web application running on static hosting. The current JSC manages prefectures separately from islands and original records separately from cited records, and links filter conditions between the distribution and image pages. It also supports searches combining multiple criteria, image enlargement and comparison, and faster display.
References
- Shinkai, A. 1999. 夢 [Dream]. Kishidaia, 77: 22–24. https://drive.google.com/file/d/1y9NdlkYJfxNnsJg5ago0oEle1LS9z2z7
- Tanikawa, A. 2000. A check list of Japanese spiders (ver. 2000). Kishidaia, 78: 79–142. https://drive.google.com/file/d/1AF_Ny554RcV6iGmEu-zHTyYAXco3ER4o
- Shinkai, A. 2001. 県別クモ類文献リストの一覧 [A List of Spider References by Prefecture]. Kishidaia, 80: 93–140. https://drive.google.com/file/d/1MGX2H9RYt5F7IQdMQeqJJgoiZR2XkYUq
- Shinkai, A. 2005. 夢の一里塚「県別クモ類分布図 Ver.2004」完成までの経緯 [A Milestone Toward a Dream: The Making of “Prefectural Distribution Maps of Japanese Spiders Ver. 2004”]. 東京蜘蛛談話会通信 [Newsletter of the Tokyo Spider Study Group], 113: 8–10. https://drive.google.com/file/d/17sLgS_q1kOOqaDWertVPHwoGZt8fKLQR
- Shinkai, A., Andoh, A., Tanikawa, A., Ikeda, H. & Kuwata T. 2024. Japanese Spiders ver.2024. Private publication. https://www.asahi-net.or.jp/~dp7a-tnkw/cd/cd.htm
- Hidaka, R. & Suzuki, Y. 2025. Building the Next Generation of the “Japanese Spiders”: An Introduction to the Japan Spider Catalog. Kishidaia, 126: 123–131. https://drive.google.com/file/d/1yPwaCVeIhWseb6b1QZYccpWGLbGp97ee
08
Future work
The current map uses prefectural-mainland polygons and representative points for islands. Statistical analysis would require checking collection localities stated in each reference and recording the actual localities as coordinates. Current JSC data contain neither coordinates nor coordinate-accuracy information. Because this would require an exceptionally large amount of work, implementation is currently on hold.
Sex, life stage, and collection date are being recorded. A seasonal-occurrence graph is planned once sufficient data have accumulated.
Collector information is also being recorded, and ways to show contributions by authors and collectors in each region are under consideration. Excessive ranking could encourage the production of low-quality records, however, so improvements in record verifiability may need to be developed at the same time.
JSC is vulnerable to misidentified records of species that could plausibly occur in the reported area, and its mechanisms for ensuring record reliability remain insufficient. More detailed record-accuracy categories and the registration of specimen repositories and determiners are under consideration, including treating original descriptions and records with images of palps or epigynes as more reliable.
09
Acknowledgements
Japan Spider Catalog inherited the data from Japanese Spiders (CD-ROM), developed by Akira Shinkai, Akihisa Andoh, Akio Tanikawa, Hiroyoshi Ikeda, T. Kuwata and colleagues.
Akira Shinkai shared the history of the development of Japanese Spiders (CD-ROM). Akio Tanikawa provided the data and advice on management policy.
Akihisa Andoh offered his views on the challenges of the prefectural spider distribution maps.
We are deeply grateful to Akira Shinkai, Akihisa Andoh, Akio Tanikawa, Hiroyoshi Ikeda and T. Kuwata for developing and updating Japanese Spiders (CD-ROM).
Members of the Tokyo Spider Study Group, SPIDERLING and the young spider enthusiasts’ group contributed lively discussions on operating the database.
This database and Japanese Spiders (CD-ROM) are built on the many collection records published in Kishidaia and other groups’ bulletins and academic journals. We sincerely thank everyone who has contributed to reporting these records.
