Corybas viridisepalus S.P.Lyon

Plant: Terrestrial herb

Tuber: ovoid, 7 × 6 mm  

Stem: slightly angular, c. 7.5 mm long 

Cataphyll: 9 mm long, apex subulate

Leaf: deep green with paler veins above, purple patches between veins below; sessile, cordate, 13–16 × 11–12 mm, slightly rugose, glabrous, margins undulate, apex apiculate, veins reticulate with two lateral veins on either side of midvein, outermost extending three-quarters of the way to the apex before anastomosing with the inner lateral veins 

Peduncle: greenish, less than 1 mm long 

Bract: green, narrowly triangular, 5–6 mm long, acute 

Ovary: cylindrical, c. 3.5 mm long, ridged 

Flower: solitary, upright ; colors as follows: Dorsal sepal pale translucent green, lateral sepals and petals whitish; outer surface of labellum tube pale green with dark purple longitudinal streaks, spurs greenish-white, inner surface of labellum blade pale green with 10 or more thin purple longitudinal stripes, these becoming irregular blotches in center of blade, and a thin purple margin, column green 

Dorsal sepal: spathulate-oblanceolate, 23 × 5 mm, glabrous, keeled, acute, 7-veined 

Lateral sepals: filiform, c. 3.5 × 1 mm, emerging from behind spurs 

Lateral petals: filiform, c. 3 × 1 mm 

Labellum: from tubular basal part, abruptly curved downward and opening into a 9 mm wide, expanded oval blade, c. 16 mm long when flattened out, blade densely hispidulous, margins minutely fimbriate, apex incised, opening to floral tube V-shaped  

Spurs: narrowly conical, c. 3.5 mm long 

Column: upright, 3 × 2 mm; ventral pad 2 × 1 mm 

Capsule: not seen 

Type: Papua New Guinea, Jiwaka Province, mountains above Minj, December 2011, S.P. Lyon SPL 408 (holotype LAE, isotype L). 

Distribution: Endemic to New Guinea, recorded from western areas of the central highlands of Papua New Guinea (Enga and Jiwaka Provinces). 

Ecology: Terrestrial in mossy montane forest 

Elevation: c. 2300–2900 m.