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Page number:174 
Remarks (public):The size of the spores deserves some remarks.
The type of P. cavernulosus Berk. is not sterile as stated by Lowe (1966:130). After repeated examinations spores were found that measured 9-12 x 4-5 µm. The dextrinoid reaction of the skeletal hyphae is very strong in this specimen. In the type of Poria delicatula the spores measured 12-16 x 4-6 µm while all intermediate sizes were found in others specimens examined. We believe that the medium sized pores, the cream to ochraceous fruitbody and the strongly dextrinoid skeletal hyphae are diagnostic for this species. The relatively large spore-variation that can be observed from the type of P. cavernulosus and of fresh specimens collected in Ecuador (see list below) probably reflects only different stages in develo µment. After having examined many specimens from Africa and America we came to the conclusion that a separation based on spore size was not possible.
The description given by Ryvarden & Johansen (1980:37) was based partly on an undescribed species with almost the same size of the spores but with yellow and non-dextrinoid skeletal hyphae. This species will be treated in a later paper.
Representative specimens: Brazil, Panuré, Ad ramos (type of P. cavernulosus, K:); Bahia, Serra da Agua de Rega, 28/II/1971. H.S. Irwin. (NY). Cuba. Coll. Wright 451. (det. P. cavernulosus by Berkeley). Panama: Marragante, leg. H. Williams 3/IV/1908 (type of Poria linearis Murr.). (NY). Ecuador: Pastaza: Curaray, 20/III/l9,90. (GB). Guyana: Tumatumari, Leg. G. Linder, 16/IX/1923. (NY). Tanzania: Usambara, Bomole, May 1902, leg. G. Zimmermann (type of Poria delicatula Henn., S). Morogoro prov. Uluguri Mts. Morning Side Res. Sta. 24/11/1973, L. Ryvarden 10944 (O). Zaire: Shaba nrov. Luisursiti, no date, leg. Thoen no 5431 (BR,O).
Description type:Non-original description 
Description:MEGASPOROPORIA CAVERNULOSA, (Berk.) Ryv. Fig. 1. comb.nov. - Basionym: Polyporus cavernulosus Berk. Hook. J. Bot. 8:235, 1856. - Poria delicatula Henn. Engl. Bot. Jahrb. 34:44, 1904. - Hexagonia heteropora Pat. J. Bot. (Morot) 3:166, 1889. - Hexagonia bartlettii Mass. Bull. Misc. Inform, Kew, 1908:216, 1908. - Poria linearis Murr. Mycologia 12:303, 1920.
Fruitbody annual, resuninate, effused, adrate and coriaceous, up to 2 mm thick.. Pore surface first white to cream, then pale strawcoloured and finally when dry and old, ochraceous to pale woody brown Pores angular and shallow, 2-4 per mm, up to 1 mm deep, pore edges finely fimbriate in actively growing specimens. Context white to pale strawcoloured.
Hyphal system trimitic, generative hyphae thinwalled, 2-3 µm wide and with clamps, often difficult to fine, skeletal hyphae dominating, thickwalled, mostly sinuous and unbranched, 2-3 µm wide and strongly dextrinoid, binding hyphae or branched skeletal hyphae also present, especially in the context, arboriform and 2-4 µm wide, strongly dextrinoid. Dendrohyphidia present, but difficult to observe in old and dry specimens, most easily seen along the pore-edges where they are abundant in young and growing specimens, hyphoid to ventricose with irregular branching in the unner part, arising from a clamp at the base, up to 25 µm long. Spores cylindrical, hyaline, thinwalled and non-amyloid, variable in size, 10-16 (18) x 5-7 µm, when young and immature apparently somewhat ellipsoid; when mature longer and slender, Habitat: On deciduous wood, Distribution: Tropical Africa and America.
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