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Page number:145 
Description type:Non-original description 
Description:Royoporus spathulatus (Jungh.) De, Comb. nov.
= Laschia spathulata Jungh., Fl. Crypt. Java, 75-76, 1838 (basionym) ; Favolus spathulatus (Jungh.) Lév., Ann. Sci. mat. Ser. III, bot., Paris, 2: 203, 1844 ; Favolus moluccensis Mont., Ann. Sci. mat. Ser. II. bot., Paris, 20 65, 1847, Polyporus moluccensis (Mont.) Ryv., Mycotaxon, 38 : 84, 1990.
Basidiocarp annual, solitary or several growing from a common point on the substratum, coriaceous and corky, very shortly stipitate ; pileus spathulate, flabelliform or dimidiate, tapering towards the base, upper surface (Fig.1) flat or slightly convex, may be depressed near the stipe, straw coloured with sharp fine radial striations ; margin thin, entire or lobed, sterile below ; hymenial surface (Fig.2) white to ochraceous, pores hexogonal, radially aligned, 1-4 per mm, dissepiments very thin, tubes up to 3 mm long ; context white, up to 1 mm thick. Stipe very short, lateral, about 5 mm in diameter and up to 8 mm long.
Hyphal system dimitic. Generative hyphae (Fig.3) hyaline, thin-walled, rarely slightly thick-walled, simple septate, branching not common, 1.5-3.5 µm wide, abundant in trama and rare in context. Binding hyphae (Fig.4) hyaline, corrugated, thick-walled, in the context showing wide lumina, in trama frequently subsolid to solid, usually dichotomously branched, 3.0-8.2 µm wide, often tapering to 1.5-2.0 µmm: Gloeoplerous hyphae (Fig.5) present, up to 8 µm wide. Basidia (Fig.6) hyaline, clavate, 4-sterigmate, 18.4-22.0 x 3.0-6.0 µm. Basidiospores (Fig.7) hyaline, thin-walled, smooth, cylindrical, non-amyloid, 5.0-8.0 x 2.0-3.0 , some with one or two guttulae. Cystidioles (Fig.8) 18.024.0 x 3.0-6.0 µm.
TYPE OF ROT : White rot.
SPECIMEN EXAMINED : BRCMH P-1993, Madhya Pradesh, India, on dead branch of an unknown angiosperm, 20.10.1993. Kept in the Mycological Herbarium, Department of Botany, Burdwan Raj College, Burdwan West Bengal, India (BRCMH). The duplicate material (HCIO 41026) has been deposited in the Herbarium of the Division of Mycology and Plant Pathology, Indian Agricultural Research Institute, New Delhi, India.
ETYMOLOGY : The generic epithet after the celebrated mycologist of India Dr. Anjali Roy (Department of Botany, Visva-Bharati University, Santiniketan, West Bengal, India).

DISCUSSION The genus Favolus Fr. (Elench. Fung., P.44, 1828) was previously regarded as distinct from the genus Polyporus Fr. (Syst. Myc. 1 : 341, 1821) due to lack of clamps in the former and their presence in the latter (Ryvarden and Johansen 1980). But Stankovicova (1973) in a detailed study of the hyphal system of Favolus brasiliensis (Fr.) Fr. [=Favolus tenuiculus Beauv.], the type species of the genus Favolus Fr., described amps. Gilbertson and Ryvarden (1987) and Ryvarden (1990) agreed, and they corrected the error in Ryvarden and Johansen
(1980) which stated the hyphae were simple septate. Due to presence of clamps in the type species of both of these genera, Favolus could not be kept as a separate genus and Corner (1984) proposed to merge Favolus Fr. with Polyporus s. str. This view was supported by Ryvarden (1990 and Teixeira (1994). Gilbertson and Ryvarden (1987); Roy, De and Pal (1994) and Teixeira (1994) have accepted the transfer of Favolus tenuiculus Beauv. (= F. brasiliensis), the type species of the genus FavoIus Fr., to the genus Polyporus Fr. made by Fries (1821). But Favolus spathulatus (Jungh. Lév., having simple septate generative hyphae (Ryvarden and Johansen 1980) could not be transferred to Polyporus along with F. tenuiculus and generic position of F. spathulatus became uncertain In 1990 Ryvarden transferred F. spathulatus to the genus Polyporus Fr. and he made a new combination Polyporus moluccensis (Ryvarden 1990) although he did not explain whether clamps were observced by him in this species. Mention may be made in this connection that Junghuhn's name Laschia spathulata of 1838 is the oldest name for this taxon but when it was transferred to the genus Polyporus, Ryvarden (1990) could not coin the name Polyporus spathulatus as this name was preoccupied by another polypore Polyporus spathulatus (Hook.) Fr. Epicr. Mycol. 1838]. Montagne described this species in 1843 as Favolus moluccensis Mont. [Ann. Sci. nat. Ser. II, bot. Paris, 20 : 36, 1843) and his name was therefore used by Ryvarden 1990). Thus Polyporus moluccensis is the name for the fungus (F. spathulatus) in the genus Polyporus.
But my study based on fresh basidiocarps revealed that F. spathulatus has simple septate generative hyphae. Thus its inclusion in Polyporus Fr., a genus characterized by the presence of clamps in all species, can not be agreed upon. Moreover, F. spathulatus exhibits a combination of characters that can not be found in any other existing genus : (a) spathulate to flabelliform basidiocarp with very short, lateral stipe, (b) poroid hymenial surface with radially aligned hexagonal pores, (c) white context, (d) dimitic hyphal system with hyaline, simple septate generative hyphae and hyaline binding hyphae, (e) hyaline, thin-walled, smooth, cylindrical, non-amyloid basidiospores, and (f) an association with a white rot of angiospermic wood.
I, therefore, propose a new genus Royoporus De to accommodate F. spathulatus and the transfer F. spathulatus: Royoporus spathulatus (Jungh.) De, comb. nov. (Basionym : Laschia spathulata Jungh., Crypt. Java, 75-76, 1838).
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