Corybas undulatus (R. Cunn.) Rupp

Plant: Small, 2 - 2.5 cm high terrestrial. 

Tuber: ovoid-globose, 4 by 4 mm.  

Stem: 3 - 5 mm long, 3-ribbed, glabrous. 

Cataphyll: tubular, 5 mm long, acute, apical part curved patently outward. 

Leaves: green above, pale green below, often tinged with purple; cordate, 7 - 20 by 5 - 18 mm, acute, base cordate, margin slightly wavy, midrib not or hardly prominent on either side, basal nerves 2 on either side of midrib, only the inner reaching apical part of limb, outer only reaching up to 1/4, looping towards inner nerve, suprabasal nerves 4 or 5 on either side of midrib, connate to inner basal nerve; pellucid lenticels none. 

Pedicel: 0 - 0.5 mm long, glabrous. 

Bract: linear, ovate at base, boatshaped, 5-6 mm long, subulate at tip. 

Ovary: ovoid-ellipsoid, 3.5 - 4.5 mm long, 3- grooved. 

Flower: dark purplish red with translucent patches, lip with white boss. 

Median sepal: erect, strongly cucullate, spathulate, 6 - 12 mm long, obtuse or apiculate, 3-nerved at base, 11 - 13-nerved on hood, the 9 inner nerves somewhat prominent on outside of hood only, scattered warty on outside of hood near tip only. 

Lateral sepals: linear, 2.5 - 3.5 mm long, glabrous. 

Lateral petals: linear, 1 mm long, sometimes absent. 

Lip: from a tubular, 4.5 - 5 mm long, basal part abruptly curved and spreading into an orbicular-cordate, 8 by 8 mm large limb, tube ventrally ventricose just below throat, tip of lip obtuse and acuminate, margin irregularly undulate-dentate, 5-nerved at base, 25 - 35-nerved near margin, hispidulous-warty on inside along margin but more pilose towards throat

Boss: widely and low conoid, white

Spurs: obliquely conoid, 1.5-2 mm, obtuse.   

Capsule: not seen.

Type: Cunningham s.n. (K).

Distribution: New South Wales, Bulahdelah (Rupp s.n.); without known loc. (Cunningham s.n.)

Ecology: In open spots in shrubberies