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 Add this item to the list   Syzygospora physciacearum Diederich sp. nov.
Page number:38 
Remarks (internal):S. physciacearum differs from S. bachmannii and S. tumefaciens by the shorter basidia and the different hosts.
In the type collection, some basidia are subspherical; they are thus reduced to the probasidia on which epibasidia developed.
I am not sure if the material included in this species is homogenous. In some specimens, the fungus is inducing the formation of distinct galls on the host thallus, whilst in others true superficial basidiomata are present. In two collections on Physcia aipolia (T. Ahti 3730 and 3973) most basidiomata are reduced and grow in the hymenium of the lichen apothecia. On Physconia grisea (J. Etayo s. n.) many basidiomata are pruinose and the pruina appears to be the same as on the host thallus.
In several specimens on Heterodermia the basidiomata are strongly tuberculate and dark brown or black. The microscopic characters noted in material on Heterodermia do not allow it to be separated from the collections on Physcia s. 1. In the specimen J. Lambinon 72/175, the context hyphae are with clamp connections, and all basidia are 3-spored. In the specimen J. D. & E. G. C. Chapman 7745B, I have seen many septa of context hyphae without clamps and one basidiospore that was refractive at the point of attachment; the single basidiospore was 3.5 x 3 µm; catenate conidia were also present. In the specimens O. Sebald s. n. and S. Tucker 6269, many asteroconidia could be observed.
It is possible that the material included here in S. physciacearum represents an assemblage of several species. As many specimens are immature, it is often difficult to detect even one single basidium or basidiospore, to prove the presence or absence of clamps, or to understand which type of conidia are produced. It would be important to culture specimens from different hosts to determine whether they are identical in all respects, but this has not been possible to date.
Description type:Original description 
Description:Syzygospora physciacearum Diederich sp. nov.
Basidiomata waxy to gelatinous, pinkish, pale brown, reddish brown, greyish brown to almost black, convex, often with a constricted base, old basidiomata often tuberculate, sometimes inducing gall formation, 0.1-1.2 mm in diam.; basidiomata sometimes reduced, growing in the hymenium of the host; context hyphae thin-walled, 2-3.5 µm in diam., clamp connections not observed in most specimens, but frequent in some specimens; haustorial branches frequent, tremelloid, mother cell subspherical to ellipsoid, 2.5-5 µm in diam., haustorial filament 0.5 µm in diam., 1-8 µm long. Hymenium mostly hyaline, sometimes with dark brown thick-walled hyphae in the outer part with cells 8-15 x 4-9 µm, containing numerous probasidia; probasidial initials ellipsoid, proliferations occurring through the basal clamp; hyphidia and cystidia absent. Basidia, when mature, cylindrical, aseptate, 24-55 x 5-7(-9) µm, rarely subspherical, 9-11 µm in diam., with (2-)3-4 epibasidia; epibasidia subulate, 1.5-2.5 µm in diam., 5-9 µm long; steriµmata refractive at the tip. Basidiospores ellipsoid or ovoid to almost limoniform, obliquely attached to steriµmata, refractive at the point of attachment, 7.5-11 x 3.5-6.5 µm. Anamorph: lunate conidia have been observed in one specimen, asteroconidia in two specimens and catenate conidia are frequent in some specimens; zygoconidia absent.
Etymology: Growing on Physciaceae.
Hosts: Heterodermia erinacea (Ach.) Hale, H. japonica (Sato) Swinscow & Krog, H. leucomela (L.) Poelt, H. sp., Physcia adscendens (Fr.) H. Olivier, P. aipolia (Ehrh. ex Humb.) Fiirnr., P. dubia (Hoffm.) Lettau, P. tenella (Scop.) DC., P. cf. tribacea (Ach.) Nyl., P. sp., Physconia detersa (Nyl.) Poelt, P. distorta (With.) Laundon and P. grisea (Lam.) Poelt. On Heterodermia, the basidiomata are frequently found growing on the cilia.
Distribution: Europe (Austria, Great Britain, Ireland, Netherlands, Spain, Sweden), Africa (Ethiopia, Rwanda), North America (Canada, U. S. A.), South America (Ecuador) and Asia (Papua New Guinea).
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