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Page number:222 
Description type:Non-original description 
Description:Bondarcevomyces taxi (Bondartsev) Parmasto, comb. nov. Basionym: Hapalopilus (Polyporus) taxi Bondartsev, Bot. Mater. Otd. Sporov. Rast. Bot. Inst. Akad. Nauk S.S.S.R. 5 (1-3): 17, 1940. Synonyms: Tyromyces taxi (Bondartsev) Ryvarden & Gilb., European Polypores 2: 693, 1994; Parmastomyces taxi (Bondartsev) Y.-C. Dai & Niemelä, Ann. Bot. Fennici 32: 222, 1995.
Figures and an additional description: Ryvarden & Gilbertson, 1994, f. 379; Dai & Niemelä, 1995, f. 5; Chang, 1996: 34, f. 12.
Rem.: Colour terminology used below is as in Kornerup & Wanscher's (1967) handbook; colour notations are as in the Munsell Book of Color (1942).
Basidiomata 3-8 x 2-12 x (0.7)-1-2.5 cm, annual, sessile, dimidiate, flabellate, thickening towards base, usually a few imbricated, rarely single, cheesy, fleshy or spongy, watery, drying brittle and very light. Odour strong, cloying sweetish, in dry specimens very strong, almost unpleasantly cloying honey-like. Pilear surface slightly floccose, soft, sometimes indistinctly zonate, when fresh orange red, brownish orange, yellowish brown, later almost tomato red or dark rust brown (Munsell: 2.5 YR - 7.5 YR 4/10, sometimes 7.5 R 3/8), near margin dark yellow to orange red (5 YR 6/13 or 7.5 R 5/14), later margin concolorous, thin, rounded or almost sharp. Pilear surface of herbarium specimens brick red or reddish brown (2.5 - 5 YR 5-6/8-10 or 4-5/6-8). Context thick, indistinctly zonate or azonate, ochraceous, light orange to almost carrot red (7.5 - 2.5 YR 6-7/12-14, later sometimes 2.5 YR 4/10), turning dark greenish or olivaceous when bruised (5 Y 5/4); in herbarium specimens butter yellow or maize yellow (2.5 Y 8/8-10, sometimes 2.5 Y 9/6), blackish in KOH solution. Tubes 3-7 mm long, cheesy or fleshy, light orange or melon yellow (10 YR 7/12 to 8/8), when bruised turning slowly olive green or honey yellow (2.5 Y 5/6); in herbarium specimens brittle, olive yellow or olive (2.5 Y 6-7/8-10) or blackish. Pores angular or slightly irregular, (0.15)-0.2-0.4-(0.6) mm in diam., (2)-3-(4) per mm, with rather thick dissepiments, pore surface light or deep orange to saffron yellow (10 YR - 2.5 Y 8-8.5/11-14), when bruised turning slowly olive (2.5-5 Y 5/6 to 5 4/4), in herbarium specimens dark olive to blackish (2.5 Y 5-6 to 5 Y 4/2-4). Spore print yellow ochre or ochraceous brown (10 YR 5-6/8-10), not changing in herbarium during many years.
Hyphal system monomitic. Generative hyphae sparingly branched, with anastomoses, thin-walled, with clamps, hyaline, (2.5)-3-5.5-(8) µm in diam., in context intermingled, in tubes subparallel and encrusted with olivaceous yellowish granules soluble in KOH solution. Gloeoplerous hyphae present, usually more abundant in tubes, slightly tortuous, sparingly branched, thin-walled, with a milky greyish or olivaceous yellow content, with rare clamps, 3-10-(15) µm in diam. Subhymenium thin, not thickening. Cystidioles or hyphidia few, (3)-4-8 µm in diam. Basidia clavate, with a basal clamp, 15-20-(22) x 5.5-7 µm, with 4 sterigmata 4-5.5 µm long. Basidiospores ellipsoid, with one side flattened, or short cylindric, with thickened smooth yellowish walls, dextrinoid, mostly with one or several guttula, (3.5)-3.8-4.8-(5.2) x 2.4-2.8-(3) µm. Species mean is 4.45 x 2.63 µm, Q = 1.69. Further, 90% expected specimen means (see Parmasto & Parmasto, 1987) are in limits 4.09-4.81 x 2.50-2.76 µm; Q = 1.58-1.80.

Causing brown cubical heart rot of living tree trunks and stumps. Substrata. On trunks of living and dead trees of coniferous families Taxaceae, Pinaceae and Cupressaceae (Chamaecyparisformosensis, Larix dahurica, Larix sp., Pinus koraiensis, Tams baccata).
Distribution. Asia: Russia, at East coast of Black Sea in Caucasus; Russian Far East, Primorsk Terr.; Northeastern China (Chilin Prov.); Taiwan, Ilan Co.
Specimens studied: RUSSIA, Krasnodarsk Terr., Khosta near Sochi, on a stump of Taxus baccata, 20 Sep 1936 L. Vasilyeva (LE, holotype); Russian Far East, Primorsk Terr, Sikhote-Alin Biosphere Reserve, Ust' Serebryanka, on base of a trunk of Larix dahurica in an Abies forest, 14
Sep 1987, U. Koljalg (TAA 150026); nearby on trunks of Pinus koraiensis, 16 Sep 1987, U. Kôljalg (TAA 150118, 150120); Sikhote-Alin Biosphere Reserve, Maisa, on base of a Larix dahurica trunk in an Abies forest, 11 Sep 1990, 1. Parmasto (TAA 150941); nearby, on a trunk of Larix dahurica, 13 Sep 1990, E. P. (TAA 151005); nearby, on base of a L. dahurica trunk, 16 Sep 1990, E. P. (TAA 151114); Siberia, South East part of Novosibirsk Reg., Salair, on a Larix stump, E. Zhukov (TAA 166178). CHINA, Changbai Forest Reserve, on base of a Larix tree, 10 Sep 1993, Y.-C. Dai 2058 (H; TAA 166337).
Remarks. According to Chang (1996), B. taxi causes white rot, according to Ryvarden & Gilbertson, 1994: 694, the rot is "presumably white". Specimens seen by me in nature caused brown heart rot of stand ing trees or stumps. Several herbarium specimens have been collected without substrate, but in two cases (TAA 150026 and 151005) typically brown-rotten wood is seen at the base of basidiomata.
The spores of B. taxi have been described as hyaline by all authors except Chang (1996: 34), who called them "hyaline to slight yellowish". We have obtained three spore prints in nature; these are all ochraceous brownish and did not change remarkably during the last eleven years. The reddish brown dark colour of older basidiomata is caused by abundant spores deposited on these during sporulation. This phenomenon is well known in polypores Fomes fomentarius and Ganoderma applanatum. The striking white or chocolate brown colour resp. of their basidiomata in sporulation periods is caused by thick cover of spores, fallen on their upper surface due to certain aerodynamical processes.
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