Holotype (PDD 27085); Isotype (Herb. HK. ZT 69/78: 'Track to Wilberg, SE of Hari Hari, Prov. Westland, N.Z.; leg. Horak, 15.II.1969'.

Pileus 10-20 mm diam., convex becoming umbonate to campanulate, margin upturned in aged carpophores, deep green at the centre, yellow towards the estriate margin, reddish-brown drying out, not hygrophanous, dry. Lamellae decurrent, lemon yellow to greenish-yellow, moderately distant, gill edge concolorous. Stipe 20-35 x 1-2 mm, cylindric or attenuated towards the base, yellowish above, deeper coloured at the base, finally becoming pinkish, glabrous, dry, hollow, single or fasciculate. Context greenish in the pileus. Odor and taste not distinctive. Chemical reaction on pileus: KOH, HCl and NH3 - green colours of the pileus fading immediately. Spores 6-8 x 4-4.5 µm, ellipsoid, smooth, inamyloid. Basidia 35-42 x 7µ,  4-spored. Cystidia absent. Cuticle a cutis of repent, cylindric hyphae (3-6 µm diam.), membrane not gelatinized, subcutis-subcellular. Clamp connections absent.

In soil under Weinmannia, Schefflera, Aristotelia, Fuchsia, etc. New. Zealand.

Pileo 10-20 mm lato, ex umbonato-convexo concavo, viridi-luteo, sicco. Lamellis arcuato-decurrentibus, limoneis vel viridi-luteis. 8tipite 20-35 x 1-2 mm, cylindraceo vel attenuato basim versus, luteolo, sicco. Sporis 6-8 x 44.5 µm, ellipticis. Cystidiis nullis. Epicute ex hyphis repentibus cylindraceisque cutem formantibus, fibulis nullis. Ad terram in silvis. Novazelandia.

This species has the colours of Gl. psittacinus (Fr.) but its spores are considerably smaller and neither pileus nor stipe are glutinous. A species closely related to H. luteovirens is reported from Japan. However, H. olivaceo-viridis Hongo (1967) differs from the N.Z. species by its emarginate-adnate lamellae, its more conic pileus, its habitat, and microscopical characters of the hyphae composing the cuticle.

Holotypus (PDD 27085): 'Wilberg, Hari Hari, N.Z.; leg. Horak, 15.II.1969'.

SPECIMENS: NZ: N, Reefton, Awarau River, ZT 2007; Reefton, Waitahu River Valley, ZT. 2018. -WL, Ngahere, Nelson Creek, Kopara Junc60n, ZT 208 1.

Pileus -30 mm, conico-convex becoming umbonate to campanulate, margin often upturned and centre depressed in aged specimens; green gradually changing to yellow, yellow-brown, brown or reddish brown with age; dry or lubricous, glabrous to minutely fibrillose or silky, sometimes splitting at striate margin, hygrophanous. - Lamellae 10-18 (1 -5) emarginate to adnate finally decurrent, ventricose, up to 5 mm wide; lemon yellow, ochre or greenish yellow, edges entire, concolorous or conspicuously golden yellow or ochre. - Stipe 20-60 x 1-4 mm, cylindrical, equal, subfusoid or attenuated towards base; green to yellowish at apex, pinkish orange at upper portion (occasionally with pale blue tinge), orange-pink to pale brown at base; dry, glabrous, hollow, brittle, single or caespitose. - Context pale green in pileus, orange with blue tinge at apex of stipe, orange-pink in base of stipe. –Odour and taste not distinctive. - Chemical reactions on pileus: KOH, HCI, and NH₃ - green, coloration soon fading away. Spores 6-8 x 3.5-4.5 um, ellipsoid. - Basidia 25-42 x 6-7 um, 4-spored, with medallion-like clamp connection at basal septum. - Cystidia absent - Pileipellis a cutis of repent, cylindrical hyphae (25 ,um diam.), membranes not gelatinised, encrusted with pigment; clamp connections absent on septa of subcuticular hyphae (Pl. 1, Fig. 8).

DISTRIBUTION: NZ (N, WL).

ECOLOGY: Common; saprobic on soil among litter under Nothofagus (N. truncata, N. menziesii), Leptospermum scoparium, Podocarpus-Dacrydium or in mixed forests. December-March.

ICON.: Horak (1973: 148); Taylor (1981: No. 48).

TYPE: NZ: WL, Hari Hari, Mt Wilberg, under Weinmannia-Schefflera-Aristotelia-Fuchsia, 15 ii 1969, Horak, PDD 27085.