There is an insect-like callus about 3.5 mm (0.1 in) long with short, reddish brown, hair-like glands in a central band.

The tip of the callus is about 1.5 mm (0.06 in) wide with shiny dark reddish or black glands.

[5] The specific epithet (rosulatus) is a Latin word meaning "of roses",[6] referring to the leaf rosette surrounding the base of the flowering stem, contrasting with others in the genus that have them on side growth.

[3] The rosetted elbow orchid grows in forest in the vicinity of Cooktown, sometimes forming spreading colonies.

[2][3][4] As with other Arthrochilus orchids, A. rosulatus is pollinated by male thynnid wasps of the genus Arthrothynnus although the species involved is not known.