Venturiales » Sympoventuriaceae

Scolecobasidium

Scolecobasidium E.V. Abbott, Mycologia 19(1): 30 (1927).

Index Fungorum number: IF 9840; Facesoffungi number: FoF 12047, 44 morphological species (Species Fungorum 2022), 20 species with molecular data.

Saprobic in soil. Sexual morph: Unknown. Asexual morph: Hyphae creeping, septate; conidiophores arising as short side branches from aerial hyphae, not erect, non-septate. Conidia elongate, two celled, smooth, light olivaceous to almost hyaline, borne singly on short, terminal, thread-like sterigmata; one to three sterigmata on each conidiophore (adapted from Abbott 1927).

Type species: Scolecobasidium terreum E.V. Abbott

Notes: Scolecobasidium is characterised by creeping, septate hyphae, and elongate, two-celled, smooth, light olivaceous to almost hyaline conidia. The shape of the conidia and the way the conidia are borne on the conidiophores are significant characters of Scolecobasidium. De Hoog and Arx (1973) studied several species of Scolecobasidium and erected the genus Ochroconis to accommodate species with ellipsoidal, clavate or fusiform, one- to four-celled conidia, having denticles gathered at the apex or in a different rachis. Scolecobasidium differs from Ochroconis in having T- or Y-shaped or bilobed, two- to many-celled conidia and ampulliform conidiogenous cells, having one to three conidium-bearing denticles at the apex of the conidiophores. Ellis (1976) considered Ochroconis as a synonym of Scolecobasidium and his treatment was followed by subsequent authors (Domsch & Gams 1980, Hamayun et al. 2009). De Hoog (1985) reported that the intraspecific variability was high and considered Ochroconis and Scolecobasidium as two distinct genera. Wellman (1975), Yarita et al. (2010) and Martin-Sanchez et al. (2012) also accepted Ochroconis as a distinct genus. Horré et al. (1999) reported that Scolecobasidium and Ochroconis comprise a polyphyletic complex based on examination of restriction fragment length polymorphism (RFLP) of rDNA small subunit (SSU) and internal transcribed spacer (ITS). Yarita et al. (2010) added a new species O. calidifluminalis based on phylogenetic analysis of SSU and ITS sequence data, which clustered sister to O. gallopava but neither Scolecobasidium spp. nor Ochroconis spp. were monophyletic in their phylogenetic tree. Hao et al. (2013) agreed with Ellis (1976) and considered Ochroconis as a synonym of Scolecobasidium based on phylogenetic analysis of LSU and ITS sequence data. The familial placement of Scolecobasidium is still unknown and the genus is currently in Pleosporales genera incertae sedis. More collections with DNA sequence data might help to solve the polyphyletic nature of Scolecobasidium and determine the correct taxonomic placement of the genus. Molecular markers available for Scolecobasidium are ITS, LSU, SSU, Actin, BTUB, RPB2, TEF-1 and mtSSU.

 

Recent News

Recent paper to be published

Recent Genus

Nothocladosporium
Phillipsiella
Curreya

Recent Species

Nothocladosporium syzygii
Phillipsiella atra
Curreya conorum