Trametes modesta

Appearance

FRUITBODY annual, pileate, applanate to slightly concave or bent downwards, single or frequently in clusters or fused laterally to compound fruitbodies, but then usually with a distinct base for each pileus, single pilei semicircular to flabelliform with a contracted base occasionally more broadly attached, up to 6 cm wide and 7 cm long, very rarely above 3-4 mm thick, flexible and tough both as fresh and dry.

PILEUS variable with age and development, first finely velutinate and soft to velvety to touch and then dull, very finely concentrically zonate, pale pinkish brown to buff with weak pink to lilac shades or café au lait, then becoming more agglutinated on the pileus and thus more glabrous, and the colour changes to paler tan to pale brown colours and usually more radially-wrinkled at this stage and some radial reddish spots or streaks may even develop. Some specimens for some unknown reason, turns more whitish when the surface agglutinates, but this is apparently more uncommon. In a large gathering of over 50 fruitbodies from a log in Thailand, only 2 were white, the other older spcimens were in shades of tan to pale fulvous.

Pileus frequently from the base covered with irregular pale outgrowths which cover the narrowly concentric zonate pileus, it is azonate and occurs partly as irregular warts and as a coherent area spreading from the base, usually in more ochraceous colours, rarely above 1 mm thick. It may be lacking in many specimens even within the same collection, and the reason for its development is obscure.

There is no cuticle on the pileus except when the reddish bay streaks develop, but this is apparently quite rare and only seen a few times.

PORE SURFACE, in actively growing or living specimens, pale pinkish-beige, buff to pale greyish-pink, when viewed obliquely paler and even whitish with a faint pink shade, pores round and small, but somewhat variable, mostly 6-10 per mm and almost invisible to the naked eye, tubes more or less concolorous with the pore surface with age tan to pale brown, non-stratified and up to 2 mm deep.

CONTEXT whitish to pink, beige or pale cocoa and this is a rather persistent characteristic, changing into pale cinnamon-pink or very pale tan with age, quite easy to squash in thin sections, fibrous, up to 2 mm thick, pale cherry red in KOH, fading after 2-5 seconds but persistent as a pale cherry red spot when dry.

HYPHAL SYSTEM trimitic, generative hyphae thin-walled, hyaline and with clamps, 2-4 µm wide, skeletal hyphae dominate in the fruitbody, straight, pale pink to yellow thickwalled, but usually with a distinct lumen, 2-5 µm, not swelling in KOH, binding hyphae fairly scarce in the context and sparingly branched, more common and more densely branched in the dissepiments, thick-walled to solid, 2-3 µm wide. SPORES cylindrical, 4.5-6 × 1.5-2(2.5) µm, thin-walled smooth and hyaline, non-amyloid. Fidalgo & Fidalgo (op.cit.) report them to be 6-7.5 × 3.5-4, thus considerably larger than for all species in the T. feei-complex.

REMARKS. The speices is related to T. feei and chiefly separated by the conspicuous pinkish colour of the latter. The difference is very distinctive when seen in the field. However, they share almost the same spores, type of fruitbody and hyphal system and the same reaction to KOH. The colour is the only reliable separating characteristic and in fact, T. feei may be considered a colour-variant of T. modesta or vice-versa.

Macroscopically T. modesta may be difficult to separate from more ochraceous and whitish specimens of T. menziezii, but the latter has a distinct white context only becoming yellow with KOH and the colour disappears rapidly. In the T. modesta the context almost always has a faint shade of pinkbuff and reacts cherry red with KOH. Even if also this reaction fades away, it will leave a pale cherry red spot where the drop was placed. This characteristic alone will usually be sufficient for a separation of more dubiously coloured specimens. The pinkish colour will also be reflected on the pore surface which is white to more ochraceous in T. menziezii. Further, the binding hyphae of T. menziezii are far more branched than those of T. modesta, this is especially the case in the context where binding hyphae are fairly rare in T. modesta, common in T. menziezii.

Naming

Trametes modesta (Kunze ex Fr.) Ryvarden, Norwegian Journal of Botany 19: 236 (1972)

Deprecated Synonyms: Coriolus albocervinus, Coriolus atypus, Coriolus cervinonitens, Coriolus clemensiae, Coriolus cuneatiformis, Coriolus parthenius, Coriolus perpusillus, Coriolus subcalvus, Coriolus substipitatus, Daedalea modesta, Fomes languidus var. monochrous, Fomes sordidus, Microporus aculeatus, Microporus albocervinus, Microporus cervinonitens, Microporus deglubens, Microporus detonsus, Microporus modestus, Polyporus albocervinus, Polyporus atypus, Polyporus atypus var. exaratus, Polyporus badius var. substipitatus, Polyporus caespitosus, Polyporus cervinonitens, Polyporus deglubens, Polyporus detonsus, Polyporus dorcas, Polyporus leiodermus, Polyporus modestus, Polyporus monochrous, Polyporus praetervisus, Polyporus splendens, Polystictus aculeatus, Polystictus albocervinus, Polystictus cervinonitens, Polystictus clemensiae, Polystictus cuneatiformis, Polystictus deglubens, Polystictus detonsus, Polystictus modestus, Polystictus parthenius, Polystictus perpusillus, Polystictus subcalvus, Polystictus substipitatus, Poria deglubens, Scindalma sordidum, Trametes atypa, Trametes badia var. substipitata, Trametes caespitosa, Trametes detonsa, Trametes luzonensis

Distribution

Pantropical, widespread in S. America, not common in Africa and only a few specimens seen from Burundi and Kenya. More common in Asia, especially in the South-Eastern part to judge from the collections in the herbaria and from our own experience in Thailand where it was found on every excursion.

Habitat

On deciduous wood of many kinds.

Uses

A source of laccase, an enzyme used in pulpwood delignification, textile dye bleaching, effluent detoxification, washing powder components, removal of phenolics from wines and transformation of antibiotics and steroids as well as in biosensors.