Morphological and anatomical investigation of New Caledonian graminoid Dendrobium (Orchidaceae) with the description of two new species

Morphological characters support the description of two new species of Orchidaceae from New Caledonia: Dendrobium butinii M.Pignal & Munzinger sp. nov. and Dendrobium letocartiorum Munzinger & M.Pignal sp. nov. The lectotypes of Dendrobium camaridiorum Rchb.f. and D. crassifolium Schltr. are designated here. A leaf anatomical study was conducted and provided useful characters to distinguish the five New Caledonian graminoid Dendrobiineae species. Two identification tools are provided: an anatomical key for sterile material of grass-like Dendrobiineae and a morphological key for the New Caledonian graminoid Dendrobium. We propose preliminary conservation assessments with IUCN criteria for the new taxa.