New Zealand: South I.: Buller: Lewis Pass, Ninas Tr., on twigs and branches of Nothofagus fusca (Hook.f) Oerst. and N. menziesii (Hook.f) Oerst., E. Shaw, 11 May 1990, PDD 60841 (holotype).

Basidiomes 3-7 mm diam., pale rose pink (10A34), colour retained on drying or sometimes darkening (10A6), attached to the substratum either laterally with a dense subiculum of white hyphae or by a lateral extension of the pileus. Basidiome extremely brittle when dried. No stipe seen. Pileus fan-shaped to reniform, convex with an inrolled margin when young, flattening with age; surface velutinous (near the margin) to villose. Lamellae well-developed, subdistant, thin, relatively broad, slightly ventricose, in 2-3 series, 5-8 principal ones converging to an excentric point; lamellar margin even and concolorous. Taste and smell unknown. Spore print unknown.

Spores 6.5x4-6.5 (5.2x5.l)µm, Q= 1.01, globose to sub-globose, occasionally broadly pyriform, hyaline, inamyloid, not dextrinoid, acyanophilic, wall very thin, collapsing easily, apiculus usually short and distinct, occasionally extending gradually from the spore to give the pyriform spore outline, often with a distinct subterminal scar. Basidia 20-22 x 8 µm, subcylindrical to clavate, relatively short and stout, extending slightly at maturity; sterigmata (2)-4, 3-4 µm long, often scarred apically. Cheilocystidia and pleurocystidia absent. Trama fairly dense, somewhat bilateral with a central region of more or less parallel hyphae, 3-4 µm diam., lateral hyphae more interwoven, slightly divergent, merging into the narrow, filamentous subhymenium. Context of fairly densely packed hyphae, 5-6 µm diam., more parallel than interwoven and difficult to squash, merging into the loosely arranged pileipellis region with upturned hyphal endings responsible for the velutinous appearance and bundles of narrower hyphae for the villi. The pileus margin is heteromorphous, composed mainly of short, cylindrical to subclavate, flexuose to geniculate hyphal endings, some basidia and a number of more irregular cells basically narrow-subulate with a distinctive, long narrow neck. All hyphae have conspicuous clamp connections, and there was no indication of a gelatinisation.

Gregarious on dead wood on the ground in Nothofagus forest.

Basidioma 3-7 mm diam., dilute roseum (10A3-4), colore retento ubi aridum vel aliquando fuscato, substrato affixum aut lateraliter cum subiculo conferto ex hyphis albis aut pileo lateraliter extenso. Basidioma fragilissimum ubi aridum. Stipes nullus conspicuus. Pileus flabelliformis vel reniformis, convexus sed postea planus, margine involuta in juventute, superficie velutina vel villosa. Lamellae manifestae, subdistantes, tenues, latiores, leviter ventricosae, in 2-3 seriebus, 5-8 lamellis principalibus convergentibus ad locum excentricum, margine plana et concolorata Odor et sapor incogniti. Sporarum imago incognita. Sporae 5-6.5x 4-6.5 (5.2x 5.1)µm, Q = 1.01, globosae vel subglobosae, aliquando late pyriformes, hyalinae, inamyloideae, haud dextrinoideae, acyanophilae, parietibus tenuissimis et facile collabentibus, apiculo plerumque curto distinctoque, aliquando extenso sensim in spora pyriformes. Basidia 20-22 x 8 µm, subcylindrica vel clavata, curtiora et latiora in maturitate paullum extensa; sterigmata 4, 3-4 µm longa, saepe cicatricata apicaliter. Cheilocystidia pleurocystidiaque absunt. Trama conferta, nonnihil bilateralis, regione centrali ex hyphis plus minusve parallelis, 3-4 µm diam., hyphis lateralibus intertextis, nonnihil divergentibus. Contextus ex hyphis confertis, 5-6 µm diam., subparallelis potius quam intertextis, compressu difficilibus, mergentibus in regionem pileipellis laxe contextam cum hyphis ad finem erectis facieique velutinae auctoribus et fascibus hypharum angustiorum ad villos. Margo pilei heteromorpha, plerumque ex hyphis curtis, subclavatis vel flexuosis vel geniculatis, aliquot basidiis immixtis, et cellulis angustis, longioribus, inaequalibus, principaliter subulatis. Gregarie in ramis mortuis in silva (Nothofagus spp.). Novazelandia.

The name reflects the all-over pink colour of the basidiomeCheimonophyllum roseum was found quite commonly on dead twigs and branches of Nothofagus fusca and a N. menziesii in the Lewis Pass area. Its all-over shell-pink colour makes it quite distinctive as compared with other described species of the genus, which are all reported to have white basidiomes. It also has broader lamellae, without interveining, and lacks a stipe. As in C. candidissimum, no zone of cheilocystidia was found, but some awl-shaped cells were found on pileus margins of C. roseum. These are very similar to the awl-shaped cheilocystidia described by Horak (1968) and Pegler (1983) for C. candidissimum, and are also believed to be hyphal outgrowths from the trama or context, as described by Reijnders & Stalpers (1992).

HOLOTYPUS: PDD 60841