Arnold
The taxon authority Arnold may refer to:
- Chester Arthur Arnold (1901–1977), U.S. paleobotanist
- Don C. Arnold, U.S. entomologist
- Douglas L. Arnold, herpetologist
- Edwin Nicholas Arnold (1940–2023), British herpetologist
- Ferdinand Christian Gustav Arnold (1829–1901; Arnold), German lichenologist
- George Arnold (1881–1962), entomologist
- Jennifer Mary Arnold (died 1989), Australian zoologist
- Johann Franz Xaver Arnold (1730–1801; J.F.Arnold), Austrian botanist
- Paula Arnold (fl. 1972; P.Arnold), mycologist
- Rachel J. Arnold, ichthyologist
- Spencer Arnold, U.S. malacologist
- Trevor Henry Arnold (born 1947; T.H.Arnold), botanist