Hygrocybe rubronivea (an agaric fungus) - vulnerable species listing

The Scientific Committee, established by the Threatened Species Conservation Act, has made a Final Determination to list Hygrocybe rubronivea A. M. Young, an agaric fungus, as a VULNERABLE SPECIES in Schedule 2 of the Act. Listing of vulnerable species is provided for by Part 2 of the Act.

NSW Scientific Committee - final determination

The Scientific Committee has found that:

1. Hygrocybe rubronivea A. M. Young (Fungi, Basidiomycota, Agaricales, Hygrophoraceae) is a small, brightly-coloured gilled fungus. It is described by Young (2000):  Pileus 7-30 mm, convex then becoming rather flattened and occasionally centrally depressed, dry, smooth or sometimes mealy, brilliant crimson, (near 8A8-10A8), margins crenulate (especially when young) to even, not cracking, may be yellow tinted.  Lamellae broadly adnate with a slight decurrent tooth, thick, widely spaced, pure white becoming cream coloured (3A2-4A2) with age, margins concolorous; veins often present on the upper lamellae surfaces and on the pileus undersurface.  Stipe 11-35x2-3 mm, more or less cylindrical although occasionally with a tendency to become flattened and frequently is sinuous, firm, smooth, dry, at first brilliant crimson, but paling with age and may become pinkish cream, the base has a tendency to become yellow tinted and this may spread upwards. Odour none, taste mild.  Spores 6.5-10.0x(3.5)4.0-7.0 µm, mean 8.4x5.4 µm, Q:1.3-1.9, mean Q: 1.6, oblong to ellipsoid and occasionally slightly constricted medially, apiculus prominent 1-2 µm.  Basidia 27-40x6-9 µm, mean 36x6 µm, Q: 4.5-7.6, mean Q: 5.6, narrowly clavate, 2- or 4- spored, clamped.  Cystidia absent.  Hymenophoral trama regular, composed of cylindrical, clamped, and occasionally inflated elements 25-60(100)x2-10 µm, lactifers present as highly refractive, tortuous and sometimes branching, clamped hyphae 2-4 µm.  Pileipellis a cutis of clamped hyphae, 3-5 µm diameter, lactifers occasionally present and similar to those in the hymenophoral trama.  Stipitipellis a cutis of hyaline, thin-walled, clamped hyphae 3-5 µm.

2. Hygrocybe rubronivea is known only from its type locality in the Lane Cove Bushland Park in the Lane Cove local government area in Sydney.

3. Young et al. (2001) indicates that the species is widespread in NSW and Queensland. However, recent surveys by the Sydney Fungal Studies Group Inc. have not provided evidence that the species is widespread in NSW, although the surveys have provided records for other  Hygrocybe species. (R & E Kearney, pers. comm. 2003). The available recent records suggest  Hygrocybe rubronivea has a restricted distribution or that conditions required for fruiting are less frequently satisfied than for other  Hygrocybe species.

4. Species in the family Hygrophoraceae are highly sensitive to pollution from run off.

5. In view of the above the Scientific Committee is of the opinion that Hygrocybe rubronivea A. M. Young is likely to become endangered in New South Wales unless the circumstances and factors threatening its survival or evolutionary development cease to operate.

Associate Professor Paul Adam
Chairperson
Scientific Committee

Proposed Gazettal date: 02/04/04
Exhibition period: 02/04/04 - 14/05/04

Reference:

Young AM, Kearney R, Kearney E (2001) Additions to the Hygrophoraceae of Lane Cove Bushland Park. Australasian Mycologist 20, 79-86.