The IUCN Red List of Threatened Species™ ISSN 2307-8235 (online) IUCN 2021: T90985422A90985434 Scope(s): Global Language: English Neostethus borneensis Assessment by: Torres, A.G., Kesner-Reyes, K. & Leander, N.J.S. View on www.iucnredlist.org Citation: Torres, A.G., Kesner-Reyes, K. & Leander, N.J.S. 2021. Neostethus borneensis. The IUCN Red List of Threatened Species 2021: e.T90985422A90985434. https://dx.doi.org/10.2305/IUCN.UK.2021-1.RLTS.T90985422A90985434.en Copyright: © 2021 International Union for Conservation of Nature and Natural Resources Reproduction of this publication for educational or other non-commercial purposes is authorized without prior written permission from the copyright holder provided the source is fully acknowledged. Reproduction of this publication for resale, reposting or other commercial purposes is prohibited without prior written permission from the copyright holder. For further details see Terms of Use. The IUCN Red List of Threatened Species™ is produced and managed by the IUCN Global Species Programme, the IUCN Species Survival Commission (SSC) and The IUCN Red List Partnership. The IUCN Red List Partners are: Arizona State University; BirdLife International; Botanic Gardens Conservation International; Conservation International; NatureServe; Royal Botanic Gardens, Kew; Sapienza University of Rome; Texas A&M University; and Zoological Society of London. If you see any errors or have any questions or suggestions on what is shown in this document, please provide us with feedback so that we can correct or extend the information provided. THE IUCN RED LIST OF THREATENED SPECIES™ Taxonomy Kingdom Phylum Class Order Family Animalia Chordata Actinopterygii Atheriniformes Phallostethidae Scientific Name: Neostethus borneensis Herre, 1939 Synonym(s): • Neostethus coronensis Herre, 1942 Taxonomic Source(s): Kottelat, M. 2013. The fishes of the inland waters of southeast Asia: a catalogue and core bibiography of the fishes known to occur in freshwaters, mangroves and estuaries. Raffles Bulletin of Zoology Supplement No. 27: 1-663. Assessment Information Red List Category & Criteria: Data Deficient ver 3.1 Year Published: 2021 Date Assessed: August 10, 2020 Justification: This species is found only in the Philippines and Borneo. It is threatened by habitat destruction and siltation due to widespread deforestation, and soil erosion. However, the risk of extinction cannot be estimated due to the lack of information on population status and the impact of threats. Therefore, this species is listed as Data Deficient. More survey work is needed to determine the population size and trends, life history, ecology, exploitation, trade, and other threats. Geographic Range Range Description: This species is known from Coron, Busuanga in the Philippines, and Borneo from Brunei Darussalam, Sabah in Malaysia and Kalimantan in Indonesia (Kottelat et al. 1993; Parenti 1989, 1996; Kottelat 2013; Herre 1953; Werner and Allen 2000). Country Occurrence: Native, Extant (resident): Brunei Darussalam; Indonesia (Kalimantan); Malaysia (Sabah); Philippines © The IUCN Red List of Threatened Species: Neostethus borneensis – published in 2021. https://dx.doi.org/10.2305/IUCN.UK.2021-1.RLTS.T90985422A90985434.en 1 Distribution Map © The IUCN Red List of Threatened Species: Neostethus borneensis – published in 2021. https://dx.doi.org/10.2305/IUCN.UK.2021-1.RLTS.T90985422A90985434.en 2 Population Information on the status of the populations throughout the geographic range is limited. Earlier records of this species from museum collections suggest that this species was common in Sabah. Recent surveys in Sabah did not find this species (Ng et al. 2017, Martin-Smith et al 1998). The population in Brunei is stable and abundant (Parenti 2014). The population in Coron is not well studied. Current Population Trend: Unknown Habitat and Ecology (see Appendix for additional information) This species occurs in rivers, river mouths, brackish water, and mangrove swamps ((Herre 1953; Parenti 1989, 1996). Neostethus species are generally transparent to opaque in colour and are surface feeding fishes that move in schools (Parenti 2014). This genus can be distinguished by a complex reproductive organ in males called the priapium, which is thought to be used to clasp females during internal fertilization (Kottelat et al. 1993). The females then lay fertilized eggs that attach to substrates such as plants via adhesive filaments (Parenti 2014). In Brunei, this species is sympatric with Neostethus geminus throughout its range (Parenti 2014). Systems: Freshwater (=Inland waters), Marine Use and Trade (see Appendix for additional information) Information on the use and trade of this species is not known. Threats (see Appendix for additional information) In Busuanga (Philippines), freshwater ecosystems are threatened by habitat destruction due to deforestation, mining activities, and sedimentation and possibly impacted by the introduction of alien species (Matillano 2011, Ng 2020, University of the Philippines Los Baños, College of Human EcologyDepartment of Community and Environmental Resource Planning et al. n.d.). In Borneo, this species may face a similar threat due to widespread deforestation and soil erosion causing siltation and increased turbidity in rivers, streams, and swamps (Kottelat et al. 1993, Ng et al. 2017, WWF 2020). Conservation Actions There are no known conservation measures for this species. Research on population status, life history, ecology, use, trade, and other threats is needed. Credits Assessor(s): Torres, A.G., Kesner-Reyes, K. & Leander, N.J.S. Reviewer(s): Capuli, E. © The IUCN Red List of Threatened Species: Neostethus borneensis – published in 2021. https://dx.doi.org/10.2305/IUCN.UK.2021-1.RLTS.T90985422A90985434.en 3 Bibliography Herre, A.W.C.T. 1953. Check list of Philippine fishes. Research Report. U.S. Fish and Wildlife Service and the U.S Department of the Interior, USA. IUCN. 2021. The IUCN Red List of Threatened Species. Version 2021-1. Available at: www.iucnredlist.org. (Accessed: 25 March 2021). Kottelat, M. 2013. The fishes of the inland waters of southeast Asia: a catalogue and core bibiography of the fishes known to occur in freshwaters, mangroves and estuaries. Raffles Bulletin of Zoology Supplement No. 27: 1-663. Kottelat, M., Whitten, A.J., Kartikasari, S.N. and Wirjoatmodjo, S. 1993. Freshwater fishes of Western Indonesia and Sulawesi. Periplus Editions, Hong Kong. Martin-Smith, K.M. and Tan, H.H. 1998. Diversity of freshwater fishes from eastern Sabah: annotated checklist for Danum valley and a consideration of inter- and intra-catchment variability. Raffles Bulletin of Zoology 46(2): 573-604. Matillano, J.D. 2011. Taxonomy and conservation of the minnow genus Puntius (Pisces: Cyprinidae) from Northern Palawan, Philippines. College of Environmental Science and Forestry, State University of New York. Ng, C.K., Abdullah, F., Biun, H., Ibrahim, M.K., Mustapha, S. and Sade, A. 2017. Review: A working checklist of the freshwater fish diversity for habitat management and conservation work in Sabah, Malaysia, North Borneo. Biodiversitas 18(2): 560-574. Ng, H.H. 2020. Ompok taytayensis. The IUCN Red List of Threatened Species 2020: e.T91212399A91212416. Available at: https://dx.doi.org/10.2305/IUCN.UK.20201.RLTS.T91212399A91212416.en . (Accessed: 14 July 2020). Parenti, L.R. 1989. A phylogenetic revision of the phallostethid fishes (Atherinomorpha, Phallostethidae). Proceedings of the California Academy of Science 46(11): 243-277. Parenti, L.R. 1996. Phylogenetic systematics and biogeography of phallostethid fishes (Atherinomorpha, Phallostethidae) of northwestern Borneo, with description of a new species. Copeia 3: 703-712. Parenti L.R. 2014. A new species of Neostethus (Teleostei; Atherinomorpha; Phallostethidae) from Brunei Darussalam, with comments on northwestern Borneo as an area of endemism. Raffles Bulletin of Zoology 62: 175-187. University of the Philippines Los Baños, College of Human Ecology-Department of Community and Environmental Resource Planning, Municipal Government of Busuanga, Municipal ECAN Board and Palawan Council for Sustainable Development. n.d.. Municipality of Busuanga ECAN Resource Management Plan 2017-2022. Werner, T.B. and Allen, G.R. 2000. A rapid marine biodiversity assessment of the Calamianes Islands, Palawan province, Philippines. RAP Bulletin of Biological Assessment 17. Conservation International, Washington, USA. WWF. 2020. The heart of the Borneo under Seige. Available at: https://wwf.panda.org/knowledge_hub/where_we_work/borneo_forests/borneo_deforestation/. (Accessed: 15 August 2020). Citation © The IUCN Red List of Threatened Species: Neostethus borneensis – published in 2021. https://dx.doi.org/10.2305/IUCN.UK.2021-1.RLTS.T90985422A90985434.en 4 Torres, A.G., Kesner-Reyes, K. & Leander, N.J.S. 2021. Neostethus borneensis. The IUCN Red List of Threatened Species 2021: e.T90985422A90985434. https://dx.doi.org/10.2305/IUCN.UK.20211.RLTS.T90985422A90985434.en Disclaimer To make use of this information, please check the Terms of Use. External Resources For Supplementary Material, and for Images and External Links to Additional Information, please see the Red List website. © The IUCN Red List of Threatened Species: Neostethus borneensis – published in 2021. https://dx.doi.org/10.2305/IUCN.UK.2021-1.RLTS.T90985422A90985434.en 5 Appendix Habitats (http://www.iucnredlist.org/technical-documents/classification-schemes) Habitat Season Suitability Major Importance? 5. Wetlands (inland) -> 5.1. Wetlands (inland) - Permanent Rivers/Streams/Creeks (includes waterfalls) - Suitable - 5. Wetlands (inland) -> 5.16. Wetlands (inland) - Permanent Saline, Brackish or Alkaline Marshes/Pools Resident Suitable - 12. Marine Intertidal -> 12.7. Marine Intertidal - Mangrove Submerged Roots - Suitable - Threats (http://www.iucnredlist.org/technical-documents/classification-schemes) Threat Timing Scope Severity Impact Score 9. Pollution -> 9.2. Industrial & military effluents -> 9.2.2. Seepage from mining Ongoing - - Low impact: 3 9. Pollution -> 9.3. Agricultural & forestry effluents -> 9.3.2. Soil erosion, sedimentation Ongoing - - Low impact: 3 Research Needed (http://www.iucnredlist.org/technical-documents/classification-schemes) Research Needed 1. Research -> 1.2. Population size, distribution & trends 1. Research -> 1.3. Life history & ecology 1. Research -> 1.4. Harvest, use & livelihoods 1. Research -> 1.5. Threats Additional Data Fields Distribution Estimated extent of occurrence (EOO) (km²): 637094 © The IUCN Red List of Threatened Species: Neostethus borneensis – published in 2021. https://dx.doi.org/10.2305/IUCN.UK.2021-1.RLTS.T90985422A90985434.en 6 The IUCN Red List Partnership The IUCN Red List of Threatened Species™ is produced and managed by the IUCN Global Species Programme, the IUCN Species Survival Commission (SSC) and The IUCN Red List Partnership. The IUCN Red List Partners are: Arizona State University; BirdLife International; Botanic Gardens Conservation International; Conservation International; NatureServe; Royal Botanic Gardens, Kew; Sapienza University of Rome; Texas A&M University; and Zoological Society of London. THE IUCN RED LIST OF THREATENED SPECIES™