Fruit bodies up to 15 x 10 mm, branched from the base, erumpent from rotten wood, lax-ascending, inverted talon-like; all parts terete, bright golden yellow to ochraceous yellow ("capucine-buff", "pale yellow-orange"), with base in age becoming rusty orange ("Mars-yellow", "xanthine-orange"); arising from sheets of flattened rhizomorphic strands of identical colours where exposed to air, or white where within wood; axils lunate; internodes diminishing gradually; hymenium amphigenous. Apices either awl-shaped or minutely dichotomous, concolourous with other parts. Odour negligible; taste bitter.
Macrochemical reactions: branch sections: KOH = avellaneous; NOH = golden; FCL = green-black; GUA = positive; ANO = black in 30 s; PYR = ambiguous; PHN = negative.
Hyphae of rhizomorphic strands generative, 2-4 µm diam., clamped, uninflated, thin-walled, involving abundant cystalline material; ampulliform clamps occasional, up to 10 µm broad, thick-walled (wall up to 0.5 µm thick), unornamented. Hyphae of branch trama skeletal generatives 3-5 µm diam., clamped, gnarled at septa or branch points, hyaline; wall up to 0.4 µm thick. Basidia 35-40 x 9-10 µm, broadly cylindrical distally, rather abruptly narrowing to an equal stalk-like portion proximally; contents multiguttulate; sterigmata 4, curved-erect. Spores (Fig. 109) 8.3-9.7 x 5.0-5.8 µm (E =1.53-1.93; E^m = 1.66; L^m = 9.05 µm), ellipsoid to ovate, somewhat flattened adaxially, roughened; wall up to 0.3 µm thick medially, thinner apically, strongly cyanophilous; hilar appendix papillate, abruptly thin-walled; ornamentation of very small raised areas on wall, strongly cyanophilous, at or beyond resolution of my microscope (x2250).

On well rotten wood of Nothofagus.

Receptacula ad 15 x 10 mm, ramosa, in ligno, dara aurantio-flava. Stipite parvulo; rhizomorphis aurantio-flavis, tenacibus, vetustioribus ferrugineo-auranths; odore nullo, sapore amaro. Hyphis monomiticis; in ramis fibulatis, non inflatis, crassitunicatis; basidiis 35-40 µm longis, fibulatis; sterigmatibus 4. Sporis 8.3-9.7 x 5-5.8 µm, ellipsoideis ad ovatis, laevibus ad vix omatis, ut in oratione infra.

COMMENTARY: This taxon is unique in subgenus Lentoramaria for at least two reasons: (i) the rather bright golden yellow of fruit bodies and rhizomorphs; (ii) virtually smooth or smooth spores.
Spore ornamentation cannot be seen at x1000, but, with cotton blue, at x2250 a hint of roughness can be seen. This is not typical of the subgenus, where spores show "normal" shagreened or tuberculate ornamentation.
With such an approach toward smooth spores, I was reminded of Lentaria pinicola (Burt) Pet., the spores of which are smoothbut otherwise very similar to those of the above. Two characters prohibit placement of Ramaria aureorhiza in Lentaria: (i) minute roughness visible on about 25% of the spores observed; and (ii) the lack of cyanophilous ornamentation of rhizomorphic strand hyphae as typical for Lentaria. Instead, the ampulliform clamps and crystalline material in the rhizomorphs of R. aureorhiza are typical of the R. apiculata complex of subg. Lentoramaria.
In gross morphology, fruit bodies are somewhat reminiscent of those of Ramaria filicicola (Fawcett) Corner, described on dead tree ferns from Australia, but that species produces skeletal hyphae in its rhizomorphs, and much smaller spores (see below).

South Island: Nelson, Haycock's Bush, Graham River Valley, 15.v.82, no. 43402 (holotype, PDD; isotype, TENN).