Search on : Taxa descriptions


Page number:222 
Description type:Non-original description 
Description:Parmastomyces taxi (Bondartsev) Y.C. Dai & Niemelä, comb. nov. (Fig. 5).
Basionym: Polyporus taxi Bondartsev, Bot. Mater. Otd. Spor. Rast. 5(1-3):17. 1940. Type: Russia. Caucasus, Black Sea, 20.IX.1936 Vasilyeva (LE, not studied). - Hapalopilus taxi (Bondartsev) Bondartsev & Singer, Ann. Mycol. 39:52. 1941. - Tyromyces taxi (Bondartsev) Ryvarden & Gilb., Synopsis Fungorum 7:693. 1994.
The species was originally described from the Black Sea coast of the Caucasus Mts., and was only lately found in Khabarovsk Terr. of Russia. Because it is a very rare and still poorly known species, we treat it here. Ryvarden and Gilbertson (1994:693) have published a modern description.
The monomitic hyphal system, and oblong-ellipsoid spores which are fairly thick-walled, strongly cyanophilous and distinctly dextrinoid, are the typical characters of Parmastomyces Kotl. & Pouzar (Kotlaba & Pouzar 1964). The characters agree well with the present species, and we propose the new combination as Parmastomyces taxi.
The genus Parmastomyces is closely related to Oligoporus: O. rennyi (Berk. & Broome) Donk, the type species of Oligoporus, and O. sericeomollis (Romell) Bondartseva have the same kind of hyphal system and similar spores as what they are in Parmastomyces, and also cause a white rot, but their spores are not dextrinoid (at least not distinctly), and their fruit bodies show no colour changes. Basidiocarps of P. mollissimus (Maire) Pouzar (syn. P. transmutans (Overh.) Ryvarden & Gilb., P. kravtzevianus (Bondartsev & Parmasto) Kotl. & Pouzar) and P. taxi become brownish upon bruising or drying.
The spores in the genus Hapalopilus P. Karst. are negative in CB and IKI. Basidiocarps of Parmastomyces taxi become grey with KOH, not pinkish red as in the species of Hapalopilus. For these reasons P. taxi cannot be included in Hapalopilus, and this was already pointed out by Ryvarden and Gilbertson (1994), who placed this species in Tyromyces P. Karst. Spores in Tyromyces are distinctly thin-walled, CB-, IKI-, and basidiocarps of Tyromyces do not change upon bruising or drying and show no colour reaction with KOH. Therefore we consider Tyromyces to be unsuitable a genus for the present species.
We want to add here a few characters to supplement the description of Ryvarden and Gilbertson (1994). In Parmastomyces taxi tramal hyphae are more or less parallel, thin- to slightly thick-walled. Contextual hyphae are strongly interwoven, thick-walled to almost solid, and they are usually encrusted with yellowish-brown crystals, making the hyphae pale brown-coloured. All hyphae are CB-, IKI-, and unchanged in KOH. Spores in our material are (3-)3.8-4.5 x (1.9-)2-2.4 µm, L=4.04 µm, W=2.18 µm, Q=1.85 (n=32/1), ie., they are smaller than those of the collection on Taxus (4-5 x 3 µm, Bondartsev 1940).
Parmastomyces taxi is a very rare species. It is only known in the Black Sea coast of the Caucasus Mts., Khabarovsk Terr. of Russia and in northeastern China, and has been reported to grow only on Larix and Taxus.
Taxon name: