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List of Replaced Descriptors

The annual updating of the thesaurus with a new edition enables:

  1. Replacement of terms with more up-to-date terminology
  2. Replacement of ambiguous terms
  3. Correction of errors

However, these changes may impact the ability to search previously indexed database records for those who use the thesaurus as a controlled vocabulary. The Thesaurus Staff makes all effort to replace deleted or modified preferred terms with a cross-reference to the new preferred term. There are 86 replaced preferred terms between the 2020 and 2021 editions.

Replaced Terms between 2020 and 2021 Editions
Previous Term: Replaced by:
Acacia farnesiana Vachellia farnesiana
Acacia karroo Vachellia karroo
Acetogenium Thermoanaerobacter
Amycolata nitrificans Pseudonocardia nitrificans
Amycolata petrophilea Pseudonocardia petroleophila
arabinitol arabitol
Arterivirus Alphaarterivirus
Astragalus mongholicus Astragalus membranaceus
Astragalus propinquus Astragalus membranaceus
Avian encephalomyelitis virus Tremovirus A
Avian sapelovirus Anativirus A
beta-glucanase glycosidases
biomass gasification biogasification
Brassica rapa var. parachinensis Brassica rapa subsp. chinensis var. parachinensis
Canine minute virus Carnivore bocaparvovirus 1
Cape Verde Cabo Verde
Ceratocystis fagacearum Bretziella fagacearum
Chaetoceros socialis f. radians RNA virus 01 Chaetoceros socialis forma radians RNA virus 1
Chinese hamsters Cricetulus griseus
Choristoneura occidentalis Choristoneura freemani
Citrus deliciosa Citrus aurantium var. chrysocarpa
Citrus reshni Citrus aurantium var. chrysocarpa
Citrus sunki Citrus aurantium var. chrysocarpa
Citrus unshiu Citrus aurantium var. chrysocarpa
Citrus viroid III Citrus dwarfing viroid
Comoviridae Secoviridae
Coridothymus capitatus Thymbra capitata
Coronavirinae Orthocoronavirinae
Cryptophlebia leucotreta Thaumatotibia leucotreta
Dhori virus Dhori thogotovirus
Duck hepatitis A virus Avihepatovirus A
Echinochloa hoja blanca virus Echinochloa hoja blanca tenuivirus
Encephalomyocarditis virus Cardiovirus A
epoxyconazole epoxiconazole
Equine arteritis virus Alphaarterivirus equid
farm tourism agritourism
Fig mosaic virus Fig mosaic emaravirus
Flanders virus Flanders hapavirus
flaviviridae infections Flaviviridae infections
High Plains virus High Plains wheat mosaic emaravirus
Human parechovirus Parechovirus A
Infectious salmon anemia virus Salmon isavirus
Influenzavirus A Alphainfluenzavirus
Influenzavirus B Betainfluenzavirus
Influenzavirus C Gammainfluenzavirus
Johnston Atoll virus Johnston Atoll quaranjavirus
Lactate dehydrogenase-elevating virus Gammaarterivirus lacdeh
Ljungan virus Parechovirus B
Lycium ferrocissimum Lycium ferocissimum
Maize stripe virus Maize stripe tenuivirus
Panthera leo persica Panthera leo leo
Parapoxvirus of red deer in New Zealand Red deerpox virus
Pennisetum alopecuroides Cenchrus purpurascens
Pennisetum clandestinum Cenchrus clandestinus
Pennisetum flaccidum Cenchrus flaccidus
Pennisetum glaucum Cenchrus americanus
Pennisetum macrostachyum Cenchrus elegans
Pennisetum macrourum Cenchrus caudatus
Pennisetum orientale Cenchrus orientalis
Pennisetum pedicellatum Cenchrus pedicellatus
Pennisetum polystachion Cenchrus polystachios subsp. polystachios
Pennisetum setaceum Cenchrus setaceus
Pennisetum setosum Cenchrus polystachios subsp. setosus
Pennisetum squamulatum Cenchrus squamulatus
phages bacteriophages
Phellinus weirii Coniferiporia weirii
picornaviridae infections Picornaviridae infections
Pigeon pea sterility mosaic virus Pigeonpea sterility mosaic emaravirus
Polyporus tomentosus Onnia tomentosa
Porcine reproductive and respiratory syndrome virus Betaarterivirus suid 1
Porcine sapelovirus Sapelovirus A
Porcine teschovirus Teschovirus A
Pseudonitzschia Pseudo-nitzschia
Quaranfil virus Quaranfil quaranjavirus
Ranunculus ficaria Ficaria verna
Raspberry leaf blotch virus Raspberry leaf blotch emaravirus
Rice grassy stunt virus Rice grassy stunt tenuivirus
Rice hoja blanca virus Rice hoja blanca tenuivirus
Rice stripe virus Rice stripe tenuivirus
Sequiviridae Secoviridae
SFTS virus Huaiyangshan banyangvirus
Simian hemorrhagic fever virus Deltaarterivirus hemfev
Simian sapelovirus Sapelovirus B
Theilovirus Cardiovirus B
Thogoto virus Thogoto thogotovirus
Uca mjoebergi Austruca mjoebergi