Here we provide a checklist of all seed plant collections (Angiosperms and Gymnosperms) present in the UBD Herbarium (UBDH). The plants are arranged in alphabetical order by family, genus and species, using the latest taxonomic classifications. UBDH contained a total of 5271 databased seed plant collections (1060 fertile, and 4211 sterile), consisting of 1386 species from 130 families. The collections covered only a limited part of Brunei Darussalam, being concentrated near the easily accessible coastal zones of Muara, Tutong and Belait, as well as near the Kuala Belalong Field Study Centre in Temburong. Because the majority of collections in UBDH came from permanent forest plots, the collections are dominated by tree families, with Dipterocarpaceae both the most collected and species rich family. We found 234 species in UBDH that were not listed in the Brunei checklist and are potentially new records for Brunei Darussalam. This would increase the known number of seed plants in Brunei by ca. 5%. The high number of new species records suggests that the Brunei seed plant flora is still incompletely known.
