Its single flower stands only 1– 3 cm tall, and has a hooded appearance as the maroon uppermost sepal hides most of the petals.

The main threat to C. carsei is modification of wetlands, both from draining for agriculture and increased nutrients from pastoral farming.

[9] Whangamarino once underwent regular fires sparked by land clearance and steam trains, but after active fire suppression began in the 1960s its vegetation changed from the mosaic of open mossy sites favoured by the orchids to tall sedges and grasses, and by 1991 the wild population of C. carsei had dropped to only 30 individuals.

To rescue the species, the Department of Conservation (DOC) began in 1994 to mimic natural disturbance by setting fires in fenced plots, in winter when the ground was damp so the underlying peat did not ignite.

[9][10][11] Corybas carsei is so vulnerable that New Zealand Geographic were only allowed to photograph plants on condition they did not reveal their exact location.