Cyathus is a genus of fungi in the family Nidulariaceae. Along with the genera Crucibulum, Mycocalia, Nidula and Nidularia, they are known collectively as the bird's nest fungi due to their small nest-like fruiting bodies containing egg-shaped peridioles. The genus Cyathus was monographed by mycologist Lloyd (1906), and later Brodie (1975, 1984), and their species concepts, especially those of Brodie (1975), are followed by most mycologists.
Taxonomic characters
The differentiation of Cyathus species is based on observable characters, such as fruiting body shape, coverings and plications of peridia, and microscopic characteristics such as the anatomy of peridioles, and the size and shape of basidiospores. The following characters are used to help identify Cyathus species:
Setae are rigid bristles made of compacted hyphae that are sometimes found at the mouth of the peridium.
The emplacement is the rounded mass of hyphae at the lower, narrow end of the fruiting body which attaches it to the growing surface.
Microscopic characters
Tunica: a thin membrane that is the outermost covering layer of the peridioles.
Cortex: in this article, the cortex refers to the tissue layer comprising the wall of the peridiole.
Spores:
Species
The following list of species is compiled from Brodie's monograph (1975) and subsequent revision (1984), as well as articles written since then describing new species or reducing others to synonymy.
experidium not plicate, woolly, hairs of equal length knotted into tight curls; endoperidium smooth with faint or irregular ridges; peridioles 2–2.5 mm in diameter, silvery with tunica
6.5–8.5 × 8.5–12 ovoid, with a distinct apiculus
L. African
C. amazonicus[2] Trierveiler-pereira & Baseia (2009)
pale brown, covered on exoperidium with tomentum; basal emplacement small and inconspicuous; endoperidium pale buff, shiny, lightly striate; lip of peridium with deep brown ring 0.5 mm wide; peridioles 1.5–1.75 mm, roughly triangular with shiny tunica[4]
15.5–17 × 15–19[4] ellipsoid to ovate or roughly spherical
Exoperidium dark brown, fruiting bodies arising from wooly base 3–mm in diameter; peridioles lenticular, 2.3 mm long by 2 mm wide by 0.6–0.9 mm thick, silvery-lead colored, with tunica.[5]
Exoperidium hairy in fresh specimens, but wears off in age, leaving surface smooth and plicate; inner surface variably plicate; peridioles dark brown, 1.5–3 mm in diameter; typically elliptical, with a thin tunica.[6]
Exoperidium with fine tomentum and long, converging downward-pointing hairs, plicate in upper third; ectoperidal surface plicate, silvery; epiphragm white with vertical tufts of hyphae; peridioles 2–2.5 mm in diameter with thick tunica, silvery when fresh, dark-brown when old.[8]
Peridium slender, obconic, thin-walled (0.2–0.4 mm); outer surface umber- or rust-colored and covered with conical tufts of hairs, not plicate, inner surface same color as outer or lighter; epiphragm pale buff with brown hairs; peridioles 2 mm in diameter, circular.[25]
Pale brown or yellow, obconic with straight sides, thin-walled; exoperidium not plicate, covered with very fine hairs; inside wall smooth, glossy; narrow basal emplacement; epiphragm pale brown or yellowish; peridioles black, elliptical, wrinkled on upper surface, 1.5–1.75 mm long; thin tunica, single-layered cortex.
5–9 × 5–7 subglobose to ellipsoid, thin-walled.[30]
Obconic or funnel-shaped, outer surface covered by greyish-white hairs and narrow tufts, plicate externally and internally, lip not setose; peridioles 1.5–2 × 1.5–1.8 mm, depressed, mostly round or ellipsoid.
15.5–18.5 × 11–15
C. limbatus Tul. & C. Tul. (1844)
British Guiana, West Indies, China, India, Africa, South America, Hawaiian Islands, Pacific Islands
Exoperidium covered with hairs pressed-down. Interior surface smooth. Peridioles approximately 1 mm, with a thin tunica. Single-layered cortex, 50 μm thick.
dark brown, fading with age, outside hirsute, faintly plicate; inside walls widely plicate, silvery-colored Peridioles are black and shiny, with a thin tunica, cortex one-layered but may appear two-layered
Flared outwards towards the mouth; exoperidium grey, fine-textured; endoperidium smooth; peridioles large, up to 3.5 wide, irregularly shaped, with tunica.[37]
Crucible shaped, pale buff-colored; thin and friable peridium walls; exoperidium covered with long down-ward-bent hairs; peridioles dark grey to black; 2 mm diameter; with a thin tunica.
Outer surface with fine hairs clumped into small mounds; cinnamon brown when dry, dark brown when moist; the mouth has a distinct red-brown band (0.2–0.3 mm wide) immediately below the rim; inside wall smooth, not plicate, lead-grey; emplacement large (7 mm); peridioles situated deep in cup, black, irregular shape (1.75–2 mm wide × 2–2.5 mm long), with depression on upper side; no tunica.
26–32 globose
L. picted (painted)
C. poeppigii Tul. & C. Tul. (1844)
Warm countries: West Indies, South America, Hawaiian Islands, Asia, Africa, China, Florida
6–8 × 6
Narrowly obconic, felty or shaggy, reddish brown to dark brown, almost black in age; both inner and outer surface deeply fluted or plicate; peridioles black and shiny. Synonymous with C. megasporus
Conic; striate on inner surface, with reddish squamules on outer surface; interior surface silvery-white; peridioles black-brown with thin tunica, 1 mm wide[10]
9–12 × 5 elliptical
C. setosus H.J. Brodie (1967)
St Lucia, Trinidad, Guadelope, Jamaica, Mexico, Bolivia
8–10 × 7–8
Mouth of cup has stiff, dark setae 0.5–1 mm long; outside surface with fine appressed hairs and some longer tangled hairs; inside surface barely plicate, silvery; basal emplacement narrow (1.5–2 mm wide); epiphragm thin, white to pale buff; peridioles angular, black, shiny, 2.5 or more wide.
^Brodie HJ. (1967). "Cyathus bulleri, a hitherto undescribed fungus of the Nidulariaceae from the West Indies". Bulletin of the Torrey Botanical Club94: 68–71.
^Brodie HJ. (1984). More bird's best fungi (Nidulariaceae) (A Supplement to 'The bird's best fungi'). Lejeunia Revue de Botanique, Nouvelle série Nº 112.
^Zhao RL, Jeewon R, Desjardin DE, Soytong K, Hyde KD (2007). "Ribosomal DNA phylogenies of Cyathus: is the current infrageneric classification appropriate?". Mycologia. 99 (3): 385–95. doi:10.3852/mycologia.99.3.385. PMID17883030.
^Zhao RL, Desjardin DE, Soytong K, Hyde KD. (2008). "A new species of bird's nest fungi: characterisation of Cyathus subgloblisporus sp nov based on morphological and molecular data". Persoonia21: 71 6.