Sebacina

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Sebacina
Sebacina schweinitzii
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Fungi
Division: Basidiomycota
Class: Agaricomycetes
Order: Sebacinales
Family: Sebacinaceae
Genus: Sebacina
Tul. & C.Tul. (1871)
Type species
Sebacina incrustans
(Pers.) Tul. & C.Tul. (1871)
Species

Sebacina alutacea
Sebacina aureomagnifica
Sebacina confusa
Sebacina cystidiata
Sebacina dimitica
Sebacina epigaea
Sebacina flagelliformis
Sebacina guayanensis
Sebacina incrustans
Sebacina ocreata
Sebacina pileata
Sebacina pseudocandida
Sebacina schweinitzii
Sebacina sparassoidea
Sebacina tomentosa

Synonyms

Cristella Pat. (1887)
Soppittiella Massee (1892)
Tremellodendron G.F. Atk. (1902)
Atkinsonia Lloyd (1916)

Sebacina is a genus of fungi in the family Sebacinaceae. Its species are mycorrhizal, forming a range of associations with trees and other plants. Basidiocarps (fruit bodies) are produced on soil and litter, sometimes partly encrusting stems of living plants. The fruit bodies are cartilaginous to rubbery-gelatinous and variously effused (corticioid) to coral-shaped (clavarioid). The genus has a cosmopolitan distribution.

Taxonomy[edit]

History[edit]

The genus was first published in 1871 by Louis and Charles Tulasne who had discovered that two species (Sebacina incrustans and Sebacina epigaea) previously referred to Corticium or Thelephora possessed septate basidia, similar to those found in the genus Tremella. Although it was unusual at that time to separate fungal genera on purely microscopic characters, Sebacina was erected for effused, Corticium-like fungi with tremelloid basidia.[1]

Subsequent authors added many additional species of corticioid fungi with septate basidia to the genus. Most, however, proved unrelated to Sebacina. In 1957 Ervin referred some Sebacina species to Heterochaetella, Bourdotia, and Exidiopsis.[2] In 1961, Wells transferred all Sebacina species having clamp connections on their hyphae to the genus Exidiopsis,[3] retaining Sebacina for the minority of species lacking clamp connections.

Current status[edit]

Molecular research, based on cladistic analysis of DNA sequences, has shown that Sebacina as previously understood includes the genus Tremellodendron (established for a group of species with coral-like basidiocarps),[4][5] but does not include some species that are not closely related to the type. These latter species have been placed in the genera Helvellosebacina and Paulisebacina.[6]

Description[edit]

Fruit bodies are typically cartilaginous or rubbery-gelatinous. In effused species (those that spread out loosely or flat), they are formed on the soil surface or in leaf litter, often encrusting fallen twigs and debris, sometimes encrusting the stem bases of living plants. In the type species, irregular or coral-like outgrowths may also be produced.[2] In some species, fruit bodies are entirely coral- or net-like.[7][6] Spores are white in mass.[2]

Microscopic characters[edit]

Fruit bodies are composed of hyphae lacking clamp connections in a gelatinous matrix. In several species the hyphal system is dimitic. The spore-bearing surface is initially covered in a layer of weakly branched hyphidia below which the basidia are formed. The basidia are tremelloid (ellipsoid and vertically septate), giving rise to long, sinuous sterigmata or epibasidia on which the basidiospores are produced. These spores are typically ellipsoid to oblong.[6]

Ecology[edit]

Sebacina species were assumed to be saprotrophic until DNA analysis of mycorrhizal roots showed that they were ectomycorrhizal plant associates.[8][9]

References[edit]

  1. ^ Tulasne LR; Tulasne C. (1871). "New notes upon the tremellineous fungi and their analogues". Journal of the Linnean Society, Botany. 13 (65): 31–42. doi:10.1111/j.1095-8339.1871.tb00079.x.
  2. ^ a b c Ervin MD. (1957). "The genus Sebacina". Mycologia. 49 (1): 118–23. doi:10.2307/3755737. JSTOR 3755737.
  3. ^ Wells K. (1961). "Studies of some Tremellaceae IV. Exidiopsis". Mycologia. 53 (4): 317–70. doi:10.2307/3756581. JSTOR 3756581.
  4. ^ Atkinson GF. (1902). "Preliminary notes on two new genera of Basidiomycetes". Journal of Mycology. 8 (2): 106–107. doi:10.2307/3752542. JSTOR 3752542.
  5. ^ Bodman MC. (1942). "The genus Tremellodendron". American Midland Naturalist. 27 (1): 203–216. doi:10.2307/2421035. JSTOR 2421035.
  6. ^ a b c Oberwinkler F; Riess K; Bauer R; Garnica S. (2014). "Morphology and molecules: the Sebacinales, a case study". Mycological Progress. 13: 445–470. doi:10.1007/s11557-014-0983-1.
  7. ^ Roberts P. (2004). "Sebacina concrescens and S. sparassoidea: two conspicuous but neglected North American Sebacina species". Sydowia. 55: 348–54.
  8. ^ Selosse M-A; Bauer R; Moyersoen B. (2002). "Basal hymenomycetes belonging to the Sebacinaceae are ectomycorrhizal on temperate deciduous trees". New Phytologist. 155 (1): 183–95. doi:10.1046/j.1469-8137.2002.00442.x. JSTOR 1513894. PMID 33873297.
  9. ^ Weiss M; Selosse MA; Rexer KH; Urban A; Oberwinkler F. (2004). "Sebacinales: a hitherto overlooked cosm of heterobasidiomycetes with a broad mycorrhizal potential". Mycological Research. 108 (Pt 9): 1003–10. doi:10.1017/S0953756204000772. PMID 15506013.