Eleven species of Thrixspermum (Orchidaceae: Vandeae: Aeridinae) newly recorded from Thailand

Eleven species of Thrixspermum are newly recorded from Thailand. Four belong to sect. Thrixspermum: T. crassilabre (South-Western floristic region), T. lampongense (Eastern floristic region), T. latisaccatum (Peninsular), and T. tortum (Peninsular); and seven to sect. Dendrocolla: T. anceps (Peninsular), T. bromeliforme (of unknown provenance), T. duplocallosum (Peninsular), T. merapohense (Peninsular), T. pardale (Peninsular), T. patkaiense (Eastern), and T. pulchellum (Peninsular). Descriptions, photographs, and notes on distribution, ecology, phenology, vernacular names, and recognition are provided. Three names are lectotypified. Five species are considered to be uncommon in the wild: T. anceps, T. crassilabre, T. duplocallosum, T. patkaiense, T. tortum; and T. bromeliforme is known from cultivation and suspected to originate in Krabi Province, Peninsular Thailand.