Search on : Taxa descriptions


 Add this item to the list  Gelatoporia Niemelä n.gen.
Page number:22 
Remarks (internal):The erection of the new genus was felt necessary, even though it is undesirable to burden the polypore system with new small genera. It was prompted by the situation of Poria subvermispora, which did not find a natural place in any of the existing genera. Doma?ski (1969) proposed Fibuloporia for it, but that genus is characterized by species with subglobose and very small spores, cottony-corky structure, straight and spaced hyphae, small and conical clamp connections, perenniality, and many other alien features. In fact, the two taxa are connected by little more than the resupinate growth habit, light colour and white-rot.
Tyromyces, proposed by Ryvarden (1973) for the species, was at that time considered to comprise most of the monomitic, light-coloured, annual polypores, causing predominantly brown-rot. So P. subvermispora did not fit well within its scope. After the studies of David (1980), however, Spongiporus (which produces brown-rot) and Leptoporus (with brown-rot and simple-septate hyphae) were separated from Tyromyces, which was left with only two species: T. chioneus as the type, and T. kmetii (Bres.) Bond. & Sing. In this restricted sense it turned out to include taxa which produce white-rot and whose context contains special, solid, rather short hyphae besides the dominant thin-walled ones. Thus Tyromyces emerged as a possible genus for P. subvermispora. At present, however, I am inclined to exclude P. subvermispora from that genus, because all the known species of Tyromyces s.str. are fleshy, able to produce pilei, their context is formed by special coralline hyphae, which are predominantly CRB negative, and their tube structure is uniform, non-hygrophanous and not gelatinized on drying. Besides, T. chioneus is dimitic.
Some degree of gelatinization is found in Skeletocutis, too. The core of that white-rot-causing genus
consists of dimitic or 'pseudo-trimitic' species, but David (1982) introduced monomitic species into it as well. They all share a special kind of encrustation (Keller 1979), not found in Gelatoporia. I am not quite convinced about the suitability of including monomitic species in Skeletocutis; anyhow Gelatoporia cannot be included in Skeletocutis s.str., or Leptotrimitus, Incrustoporia or Piloporia, which are all dimitic or 'pseudo-trimitic'.
The genus Gloeoporus (sensu Ryvarden & Johansen 1980) deserves consideration, especially since it has long included P. pannocincta. Gloeoporus is characterized by a merulioid hymenium, which lines the pore mouths in a continuous layer. On account of this feature, Gloeoporus is generally regarded as a distant relative of the true pore fungi.
Rigidoporus (incl. Physisporinus) and Henningsia (Ginns 1979) resemble the new genus in often being hygrophanous-gelatinous, in having a monomitic structure and bottle-shaped cystidioles, and in causing white-rot. However, they have globose spores and are consistently clampless. The latter feature is further supported by the absolute lack of clamp connections in the related Oxyporus and Leucophellinus (Parmasto 1983), and seems to have considerable value in that group.
Bjerkandera resembles Gelatoporia in having gelatinous tubes (B. adusta (Willd.: Fr.) Karst.) or a gelatinous layer above the tubes (B. fumosa (Pers.: Fr.) Karst.), cyanophilous hyphae and white-rot, but differs in producing pilei, having robust contextual hyphae with prominent clamp connections and an-other spore type. Further, the gelatinized (or rather, resinous) parts of Bjerkandera look quite different in the microscope, being formed of tortuous hyphae glued together with coloured matter (which gives a grey tone to the pores), instead of the tightly arranged, subparallel hyphae.
Ceriporiopsis is a genus with white-rot-causing species. In contrast to Gelatoporia, its species have fragile and non-hygrophanous tubes, whose structure does not differ sharply from that of the subiculum. Their spores are reniform to ellipsoid, have another type of basidium and no cystidioles.
Dichomitus, Diplomitoporus and Flaviporus, though causing a white-rot, exhibit a strong dimitic hyphal structure, which has no equivalent in the genus Gelatoporia.
As only a few species are now ascribed to Gelatoporia, the less critical characters of the genus may still change. If roundish spores are acceptable, Poria rivulosa (Berk. & Curt.) Cooke seems to belong here. The cultural characters of P. subvermispora and P. rivulosa are surprisingly similar (Stalpers 1978, Nakasone 1981), and the latter has gelatinous tubes and prominent cystidioles. Poria mentchulensis Pilát, too, seems to be connected with the new genus.
Description type:Original description 
Description:Gelatoporia Niemelä, n.gen.
Fruit bodies annual, resupinate, light-coloured; tubes soft and hygrophanous when fresh. Hyphal system monomitic; hyphae with thin or slightly and evenly thickened walls but lacking solid side branches or other differentiated hyphal types, hyaline, with clamp connections, CRB+, glued together into a gelatinized structure in dry tube dissepiments, adjacent subiculum or both; dissepiment structure often layered with special medullary hyphae; hymenial cystidia absent, but bottle-shaped cystidioles some-times present; spores cylindrical, IKI-, CB-. Causing white-rot on both coniferous and deciduous trees.
Taxon name: