Artomyces pyxidatus
A coral fungus 2-10 cm high, initially creamy white to yellow, sometimes white to pinkish white, browning with age, with many branches in the form of a candelabra, each branch apex with a central depression and multiple pointed tips resembling a minute crown, found on rotted, often moss-covered hardwood and occasionally softwood logs.
Basidiomata candelabra-like, 2-8(-13) cm high, usually in groups, white to pinkish white or light yellow when young, fading with age to pale yellow in upper branches, downwards becoming light yellowish brown to moderate yellowish brown, when very old becoming completely brownish; single to multiple branches arising from single stems, branching in whorls in 2-5 ranks; primary branches 1-3 mm wide; secondary branches about 1 mm thick; branch tips crown-like, with a central depression and multiple new branch initials forming around the rim; stipe slightly covered with light brown to moderate brown hyphal bundles; basal pad spreading, light brown to moderate brown, also covered in brown hyphal bundles; texture pliable, somewhat tough, flesh white to pale yellow, inamyloid (no reaction to iodine-containing solutions); taste slowly becoming acrid; on rotten deciduous and conifer wood, most often moss-covered.
Contextual tissue aerenchymatous (spongy); generative (living) hyphae up to 16 µm wide, inflated, clamped, hyaline, thin- to slightly thick-walled (wall up to 0.5 µm thick). Gloeoplerous hyphae (highly refractive hyphae) 3-7 µm wide, septate (with clamp) at base, often culminating in the hymenium as gloeocystidia, with refractive contents black in sulfobenzaldehyde. Subhymenial generative hyphae 1.6-4.0 µm wide, tightly interwoven, short-celled (10-50 µm), thin-walled, hyaline, clamped; gloeoplerous hyphae as above. Hymenium plus subhymenium 30-50 µm thick. Basidia (17-)20-28(-30) x 4.0-4.5(-50) µm, 2.0 µm wide at base, thin-walled, hyaline, clamped, (2-)4-sterigmate (“with horns”); sterigmata 3.5-4.5 µm long, slightly curved. Basidiospores (3.5-)4.0-5.0 (-5.5.) x 2.0-2.6 (-3.0) µm, white in mass, amyloid, minutely rough, thin-walled. Gloeocystidia (highly refractive sterile cells between basidia) (3-)4-6(-18) µm wide, projecting up to 15 µm beyond basidia, cylindrical mucronate (with a short sharp point) or ventricose (swollen in the middle), usually arising from subhymenial or contextual gloeplerous hyphae but occasionally from generative hyphae in subhymenium. Leptocystidia (smooth, hyaline cells between basidia) 3-5 µm wide, ventricose-rostrate (swollen in the middle with a beak), filamentous or occasionally dichotomously branched, hyaline, clamped at the base, projecting up to 8 µm beyond basidia.
Description adapted from Dodd, J. L. (1972). The genus Clavicorona. Mycologia, 737-773.
Not formally assessed. Considered Extinct 1920 in the current but unofficial Red Data List of British Fungi (Evans et al. 2006), but rediscovered in East Suffolk in 2012.
Most likely to be confused with a complex of species around Ramaria stricta, but these and other Ramaria species are macroscopically less elegantly whorled in their growth forms; possess irregularly pointed branch tips rather than delicate crown-like structures; and have considerably larger basidiospores.
Artomyces pyxidatus grows on rotten deciduous and conifer wood.
In GB&I, Artomyces pyxidatus is known only from a historic record and illustration from a collection in Worcester VC37 in 1896, and a recent vouchered specimen from East Suffolk VC25 in 2012.