This is the latest version of the dataset initially published to GBIF by the Invasive Species Specialist Group (ISSG) on behalf of the U.S. Geological Survey on October 12, 2020, at https://www.gbif.org/dataset/6b64ef7e-82f7-47a3-8ddb-ec6794ea07d6. Like that checklist, this version presents validated and verified national checklists of introduced (alien) and invasive alien species at the sub-country level. The other two related checklists for the United States, also newly published separately as V2.0, are for the States of Alaska and Hawaii.
Differences between two previous versions and ver.2.0, 2022 (this dataset): SIZE: the first version V1.0 - 5,006 accepted names (arthropods were not included); the previous version - 8,654 accepted names and two unranked hybrids; ver.2.0, 2022 (this dataset) - 8,525 accepted names and two unranked hybrids. OTHER DIFFERENCES: the previous version provided: a broader inclusion of arthropods; approximate dates of introduction (where available); 4,693 references; improved disambiguation of scientific names; biocontrol species information (where applicable); taxonomic synonyms, where available, in taxonRemarks field; unique occurrenceIDs; no habitat information; ver.2.0, 2022 (this dataset) adds pathway and habitat information, where available, more precise management of names and synonyms (and so is smaller than the previous version), and additional data on approximate dates of introduction.
OVERVIEW: Introduced (non-native) species that becomes established may eventually become invasive, so tracking introduced species provides a baseline for effective modeling of species trends and interactions, geospatially and temporally. The umbrella dataset, called United States Register of Introduced and Invasive Species (US-RIIS), is comprised of three lists, one each for Alaska (AK, with 545 records), Hawaii (HI, with 5,628 records), and the conterminous (or lower 48) United States (L48, with 8,527 records, this dataset). Each list includes introduced (non-native), established (reproducing) taxa that: are, or may become, invasive (harmful) in the locality; are not known to be harmful there; and/or have been used for biological control in the locality.
To be included in the Global Register of Introduced and Invasive Species - United States (Contiguous), or GRIIS-L48 (with L48 meaning the Lower 48 Conterminous United States), a taxon must be non-native everywhere in the locality and established (reproducing) anywhere in the locality. Native pest species are not included.
Each record has information on taxonomy, a vernacular name, establishment means designation (introduced unintentionally, or assisted colonization), degree of establishment (established, invasive, or widespread invasive), hybrid status, pathway of introduction (where available), habitat (where available), whether a biocontrol species, dates of introduction (where available; currently 46% of the records for the conterminous United States), associated taxa (where applicable), native and introduced distributions (where available), and citations for the authoritative source(s) from which this information is drawn. The umbrella dataset US-RIIS builds on a previous dataset, A Comprehensive List of Non-Native Species Established in Three Major Regions of the U.S.: Version 3.0 (Simpson et al., 2020, https://doi.org/10.5066/p9e5k160).
There are 14,700 records in the master list (USRIISv2_MasterList) and 12,571 unique scientific names. The list is derived from more than 5,800 authoritative sources (USRIISv2_AuthorityReferences) and was reviewed by (or based on input from) more than 30 taxonomic experts and invasive species scientists.
Many thanks to these reviewers and contributors: Coauthors Pam Fuller (USGS Emeritus), Kevin Faccenda (University of Hawaii), Neal Evenhuis (Bishop Museum), Janis Matsunaga (Hawaii Department of Agriculture), and Matt Bowser (US-Fish and Wildlife Service); contributors Rachael Blake (data science), National Socio-Environmental Synthesis Center (SESYNC); M. Lourdes Chamorro (Curculionidae), USDA-ARS Entomology; Meghan C. Eyler (data reviewer), US Fish & Wildlife Service; Danielle Froelich (Hawaiian botany), SWCA Environmental Consultants; Thomas Henry (Heteroptera), USDA-ARS Entomology; Sam James (Annelida), Maharishi University; Nancy Khan (Hawaiian botany), Smithsonian Institution; Alex Konstantinov (Chrysomelidae), USDA-ARS Entomology; Andrew P. Landsman (Arachnida), National Park Service, C&O Canal National Historical Park; Christopher Lepczyk (Vertebrata), Auburn University; Sandy Liebhold (Coleoptera), USDA-FS; Steven Lingafelter (Cerambycidae), USDA-APHIS; Walter Meshaka (Herpetology), State Museum of Pennsylvania; Gary L. Miller (Aphididae), USDA-ARS Entomology; Allen Norrbom (Tephritidae), USDA-ARS Entomology; Shyama Pagad (global invasive species), IUCN SSC Invasive Species Specialists' Group; John Reynolds (Annelida), Oligochaetology Laboratory; Alexander Salazar (Lycosidae), Miami University, Ohio; Elizabeth A. Sellers (data manager), USGS; Derek Sikes (Alaskan invertebrates), University of Alaska; Bruce A. Snyder (Annelida), Georgia College and State University; Alma Solis (Pyralid moths), USDS-ARS at the Smithsonian Institution; Rebecca Turner (data manager), Scion Inc., New Zealand; Darrell Ubick (Arachnida), Cal Academy; Warren Wagner (Hawaiian botany), Smithsonian Institution; Mark Wetzel (Annelida), Illinois Natural History Survey; and James D. Young (Lepidoptera), USDA-APHIS-PPQ-PHP. Our apologies to the many contributing experts we may have inadvertently omitted.
Simpson A, Sellers E, Pagad S (2023). Global Register of Introduced and Invasive Species - United States (Contiguous) (ver.2.0, 2022). Invasive Species Specialist Group ISSG. Checklist dataset https://doi.org/10.5066/p9kfftod accessed via GBIF.org on 2026-06-14.
