Studies in Laeticorticium (Aphyllophorales, Corticiaceae) and related genera

M. J. LARSEN & R. L. GILBERTSON

Larsen, M. J. & Gilbertson, R. L. 1977. Studies in Laeticorticium (Aphyllophorales, Corticiaceae) and related genera. Norw. J. Bot. 24, 99-121. Nineteen species in the genera Laeticorticium, Dendrocorticium, and Dentocorticium are presented. Four species are described as new: Laeticorticium griseo-effusum Larsen & Gilbertson, Dendrocorticium piceinum Lemke, D. violaceum Jacks., and Dentocorticium brasiliense Larsen & Gilbertson. One new combination is proposed, Dendrocorticium roseocarneum. Basidial ontogeny and position of basidia in basidiocarps are emphasized as primary taxonomic criteria in delimiting these genera. The type of mating system is implicated as possible taxonomic criterion at the generic level, and keys to genera and species are provided. Species descriptions are supplemented with line drawings of microscopic characters, and data on sub­ strate relationships and geographic distributions are given. M. J. Larsen, Center for Forest Mycology Research, Forest Products Laboratory, Forest Service, U. S. Department of Agriculture (maintained in cooperation with the University of Wisconsin), Madison, Wis. 53705, U. S. A. R. L. Gilbertson, Department of Plant Pathology, University of Arizona, Tucson, Ariz. 85721, U. S. A.

The genus Laeticorticium was erected by and do not mature until the spring or early Donk (1956), who transferred five species summer following the season in which into the genus. These are Thelephora rosea development begins. The spores are hyaline. Pers. per Fr. (nomenclatural type), Corticium non-amyloid, ellipsoid to broadly ellipsoid, polygonioides Karst., C. jonides Bres. in and pink to pinkish rose in mass. Cystidia are Brinkm., Aleurodiscus minnsiae Jacks., and usually absent. A. pini Jacks. Stereum roseocarneum Schw. The catahymenium may be an adaption to and Hydnum sulphurellum Pk. were transfer­ the relatively dry environmental conditions red to Laeticorticium by Boidin (1958) and under which the basidiocarps are formed. Gilbertson (1962), respectively. Seven species The species included in the genus have have recently been described as new. These basidiocarps that usually develop on the lower are L. lundellii (Eriksson 1958), L. ussuricum surface of small dead branches attached to and L. pilatii (Parmasto 1965), L. canfieldii, standing trees. These branches tend to dry out L. durangense, and L. mississippiense (Lar- very quickly, but probably retain enough sen & Gilbertson 1974a), and L. appalachien­ moisture to support fungus growth for short se (Burdsall 1976). periods of time. During wet periods in the Laeticorticium is characterized in part by a fall, basidiocarp development ensues with catahymenium, below which the basidia origi­ probasidia forming in or adjacent to the nate deep in the subiculum as probasidia, and subiculum. Probasidia eventually become become greatly elongated while growing noticeably thick-walled, a characteristic which through a previously developed layer of apparently enables them to retain viability dendrohyphidia with more or less intricate under adverse conditions. During more terminal branching. It is also characterized favorable periods these probasidia are stimu­ by basidiocarps that are typically bright lated by moisture and higher temperatures to colored, develop as small scattered patches, produce metabasidia. 100 M. J. Larsen & R. L. Gilbertson

Probasidia are apparently quite resistant of these branches. There are no observations to dessication. In the laboratory we have associating these fungi with heartrot in living observed that portions of basidiocarps from trees. collections made up to 10 years previously, when incubated under more optimal condi­ TAXONOMY tions, discharge basidiospores. These portions, The distinctive nature of laeticorticioid fungi attached to petri dish covers and suspended was first recognized by Bourdot & Galzin over agar, contained viable probasidia which (1928), who grouped two of the species re­ subsequently had undergone metabasidial corded from France (L. roseum and L. elongation and sporulated. polygonioides) in a section Aleurodiscoidea In Dendrocorticium and Dentocorticium a in the genus Corticium. Jackson (1950) point­ catahymenium is also present, but it is not ed out the close relationship of these species always a continuous and distinctly recogniz­ with Aleurodiscus and predicted that the able tissue layer. This condition is also found group ‘ . . . will ultimately contain several in some species of Laeticorticium. In the two recognizable species and when better under­ former genera, however, basidial ontogeny stood it may be found logical to include them differs from Laeticorticium. In Dentocorti­ in a genus separable from Aleurodiscus.’ cium, basidiocarps may or may not be formed Donk formally proposed Laeticorticium in in the growing season prior to the year of 1956, and subsequently, Lemke (1964a, b) sporulation. Probasidia are absent. Basidia excluded it from his treatment of Ale­ are typically clavate, show no metabasidial urodiscus. elongation, and are found juxtaposed to the Parmasto (1968) recognized three sections dendrohyphidia of the catahymenium. in the genus. In the section Laeticorticium he In Dendrocorticium, probasidia are thin- placed L. roseum, L. pini, L. minnsiae, L. walled and positioned in the subhymenial pilatii, L. polygonioides, L. jonides, and area. Our data indicate that they are formed L. lundellii. This section is characterized by in the same growing season in which metab­ a smooth to radially veined hymenophore, asidial elongation and sporulation occurs. resupinate basidiocarps with a white to pur­ The exception is D. piceinum, in which a plish brown or ochraceous hymenial surface, probasidial stage accompanied by metab­ and ellipsoid to ovoid basidiospores 4 µm or asidial growth is not readily apparent, but more wide. His section Roseocorticium con­ basidiospore morphology suggests that it be tains only L. roseocarneum and is characteri­ placed in Dendrocorticium. We have observed zed by reflexed basidiocarps, a smooth, also that basidiocarps of some species of purplish to brownish purple hymenial sur­ Dendrocorticium may contain viable prob­ face, and ellipsoid spores more than 4 µm asidia after extended periods of herbarium wide. The third section, Dentocorticium, storage as do those of species of Laeticorti­ contains L. ussuricum. It is characterized by a cium. hymenial surface that becomes papillose and The probasidium is not a unique character is purplish brown to yellow. The basidiospores of laeticorticioid fungi, for it appears to be are cylindric and less than 4 µm wide. present in a variety of forms in other major Laeticorticium sulphurellum was also listed fungal groups besides the corticiaceous Aphyl­ as allied to this section. lophorales. Its formation, occurrence, and Boidin et al. (1968) and Boidin (1971) have function in the life cycle is suggestive of the proposed taxonomic groupings within Laeti­ teliospore stage in many of the Uredinales. corticium based on nuclear behavior and A striking similarity may also be seen with sexuality in the life cycles of various species. some members of the genus Septobasidium They did not include in their groupings L. (see Couch 1938). minnsiae, L. pini, and L. roseum (group A) All of the species treated herein produce (the L. roseum cited was their group B). a white rot and/or positive oxidase reaction Reasons for the exclusion of these species in culture. They occur on dead wood on the were not given. To date, Boidin’s scheme ground, but more frequently on dead branches has not lent itself to coordination with taxo­ attached to standing trees, and play an im­ nomic data and conclusions derived by other portant role in the decay and natural pruning methods. Laeticorticium and related genera 101

In a recent paper by Larsen & Gilbertson (1974b), the taxonomy of Laeticorticium was further restructured (Fig. 1) primarily on the basis of positional origin and ontogeny of basidia, previously discussed herein. The relationship of L. pilatii to these genera is still uncertain, as the nature of the basidium remains obscure. For the present it is main­ tained in Laeticorticium as originally de­ scribed and included here under Species Incertae Sedis.

SEXUALITY The types of mating systems have been reported for several of the species under consideration and are summarized in Table I. It is apparent that only about half of the presently recognized species treated here have been investigated with regard to mating systems. With the exception of homothallic L. roseum, species of Laeticorticium which have been investigated are heterothallic and bipolar (with the possible exception of L. canfieldii), while those of Dendrocorticium Fig. 1. Longitudinal sections of basidiocarps rep- and Dentocorticium are heterothallic and resentative of Laeticorticium, Dendrocorticium, and Dentocorticium illustrating comparative posi- tetrapolar. The type of mating system appears tional and ontogenetic relationships of basidia in at present to support the segregation of the three genera (diagrammatic). Laeticorticium sensu stricto from the two newly recognized genera.

Table I. Sexuality in species of laeticorticioid fungi 102 M. J. Larsen & R. L. Gilbertson

METHODS long, negative in Melzer’s reagent, acyano­ Free hand sections of basidiocarps were philous; spore print pink to rosaceous pink. treated first with 95% ethanol, 10% KOH, Nomenclatural type species Laeticorticium and finally stained with 1% phloxine. roseum (Pers. per Fr.) Donk. Melzer’s reagent (for formula see Slysh 1960) KEY TO THE SPECIES OF was used for detection of amyloid or dex­ LAETICORTICIUM trinoid structures and cotton blue for cyano­ phily. Illustrations were prepared with the 1. Basidiospores frequently over 10 µm aid of a camera lucida and Zeiss drawing wide ...... 2 tube. Numerical-capital letter color designa­ 1. Basidiospores usually less than 10 µm tions are from the Munsell system (1929­ wide ...... 5 1942). Herbarium abbreviations are those of 2. Basidiocarps formed primarily on the Holmgren & Keuken (1974). underside of hemlock branches, some­ times on other conifers, often asso­ ciated with a sterile sclerotial stage on KEY TO GENERA the upper side of branches; basidio­ 1. Probasidia absent; basidia arising in, spores 12-15 × 9-11 µm ...... or directly adjacent to, catahymenium; L. minnsiae basidiospores rarely exceeding 4 µm in 2. Basidiocarps formed on other hosts; diameter ...... Dentocorticium (p. 117) sterile sclerotial stage absent; basidio­ 1. Probasidia present; if absent, then spores 16-24 × 8-12 µm ...... 3 spores ellipsoid; spores usually greater 3. Basidiocarps formed on dead branches than 4 µm in diameter ...... 2 of standing aspen ...... 2. Thick-walled probasidia formed di­ L. roseum rectly adjacent to, or barely in, the 3. Basidiocarps formed on members of subiculum; basidia usually greater than the Pinaceae ...... 4 8 µm in diameter and frequently 75­ 4. Basidiospores broadly to narrowly el­ 100 µm + long; basidiospores usually lipsoid; basidiocarps pale pink; on 12 µm or more long . . . . Laeticorticium Pinus ponderosa in Mexico ...... s. str. (p. 102) L. durangense 2. Probasidia not noticeably thick-walled, 4. Basidiospores cylindrical to narrowly usually formed in the subhymenium; ellipsoid; basidiocarps grayish white; basidia usually less than 8 µm diame­ on Pseudotsuga menziesii in Arizona ter and less than 75 µm long, frequently L. griseo-effusum projecting noticeably above the cata­ 5. Basidiocarps occurring only on Pinus hymenium when mature; basidiospores strobus; basidiospores 9-11 (-13) × rarely longer than 12 µm Dendrocorti­ 5-7.5 (-9) µm ...... cium (p. 110) L. pini 5. Basidiocarps occurring on angiosperms; basidiospores various ...... 6 THE GENUS LAETICORTICIUM 6. Basidiospores 9-12 × 7-9 µm ...... Laeticorticium Donk, Fungus 26:17. 1956. L. roseum - group B Basidiocarps annual or biennial, occurring 6. Basidiospores larger, up to 18 × 11 µm 7 in small scattered patches; hymenia1 surface 7. Basidiospores 15-18 × 8-11 µm; smooth to granulose, brightly colored; hyphal basidia 40-65 (-75) × 9-13 µm . . . . system monomitic; mature basidia formed L. mississippiense from outgrowths of thick-walled probasidia, 7. Basidiospores 11-15 × 6-8.5 µm; from which originate elongated, flexuous basidia 70-125 × 7-9 µm ...... 8 metabasidia growing instrusively through a 8. Dendrohyphidia frequently becoming layer of dendrohyphidia, becoming 75-100 cystidioid with apices capitulate . . . . µm+ long; clamp connections present through­ L. appalachiense out; cystidia and pseudocystidia usually ab­ 8. Dendrohyphidia not becoming cys­ sent; basidiospores hyaline, ovoid, broad to tidioid ...... cylindrical-ellipsoid, usually 12 µm or more L. canfieldii Laeticorticium and related genera 103

Laeticorticium appalachiensis Burds. & Lar­ subiculum white; sterile margin narrow or sen in Burds., J. Elisha Mitchell Sci. Soc. 91: absent, when present villose and white. 343-345. 1976. Subicular hyphae 2.5-4 µm diam, septate, Basidiocarps annual or biennial, effused, with clamps, thick-walled, hyaline; dendro­ beginning as small patches, finally enlarging hyphidia (Fig. 6) forming a distinct cata­ and coalescing, up to 4 × 1 cm, up to 0.25 hymenium of extensively and intricately mm thick, pruinose; fertile area yellowish branched hyphae, clamped; probasidia (Fig. white to grayish yellow when dry (near 2.5 7) somewhat globose to irregular in outline, Y 8/4), surface smooth; margin up to 1 mm frequently thick-walled, usually located di­ broad, thin, pubescent, concolorous with the rectly adjacent to, but not in, subicular tis­ fertile area to white; subiculum inconspicu­ sue; basidia (Fig. 8) 90-120 × 8-9 µm, sinu­ ous, concolorous with or paler than the ous-clavate, 4-sterigmate, with sterigmata up hymenial surface. to 6 µm long; basidiospores (Fig. 9) 13-15 X Subicular hyphae 2-4 µm diam, septate, 6-8.5 µm, broadly ellipsoid, sometimes with clamps, hyaline, smooth or heavily tapering noticeably towards the apicular end. encrusted with hyaline crystals; dendro­ Laeticorticium canfieldii is morphologically hyphidia (Fig. 2) arising from subicular very similar to L. roseum, L. durangensis, and hyphae, irregularly branched toward the L. roseum-group B (Boidin et al. 1968). apex, with ends of branches often cut off by However, the basidiospore size of the homo­ septa and with tips collapsing, smooth or thallic L. roseum on Populus sp. is 17-24 × encrusted with hyaline granules, clamped at 8-12 µm, while those of L. durangensis (on base and often clamped in branched portion, Pinus ponderosa Laws.) and L. roseum­ hyaline, frequently capitulate at apex and group B, are 16-24 × 8-12 µm and 9-12 × appearing cystidioid, up to 7 µm across, 7-9 µm, respectively. smooth to somewhat encrusted; probasidia (Fig. 3) formed directly adjacent to or within Specimen examined subicular tissue, variously shaped but often obpyriform, 12-18 µm broad, with slight wall U.S.A. ARIZONA. Graham County, Pinaleno thickening at base; basidia (Fig. 4) (including­ Mts., on Juglans major (Torr.) Heller, Can- meta- and probasidia) 70-125 × 10-12 µm field 72-11 (holotype in ARIZ; isotype in (at apex), narrowly clavate or cylindrical, CFMR). flexuous, 4-sterigmate, sterigmata up to 7 µm long; basidiospores (Fig. 5) 12-15 (-18) × Laeticorticium durangense Larsen & Gil­ 7-8 µm, ovoid to broadly ovoid, adaxially bertson, Can. J. Bot. 52:688. 1974. flattened, with distinct apiculi. Basidiocarps biennial, adnate, occurring in Lacticorticium appalachiense is distin­ small patches and effused up to 4 × 3 cm, guished by the unique form of dendro­ up to 0.4 mm thick; hymenial surface smooth hyphidia. It appears to be allied to L. and undulating, becoming pulverulent, pale canfieldii and L. mississippiense. pinkish buff (near 7.5 YR 4/8), cracking on drying and exposing a pale pink to pale Specimens examined orange layer of tissue below the hymenial U.S.A. TENNESSEE. Sevier County, Great surface; subiculum white; sterile margin Smoky Mountains National Park, on Vitus abrupt, narrow, pruinose, paler than hymenial sp., Burdsall 3890, 3893 (holotype 3893 in surface. CFMR; isotypes in BPI, VPI, and TAA); on Subicular hyphae 2.5-4 µm diam, thick- Nyssa silvatica Marsh., Burdsall 3894 walled, hyaline; dendrohyphidia (Fig. 10) (CFMR). forming a distinct catahymenium, 3-4 µm diam, intricately branched, with clamp con­ Laeticorticium canfieldii Larsen & Gilbert- nections at septa: probasidia (Fig. 11) thick- son, Can. J. Bot. 52:687. 1974. walled; basidia (Fig. 12) 40-50 (-70) × 10-12 Basidiocarps apparently biennial, effused µm, clavate, normally sinuous and contorted, in small patches, separable in small pieces. 4-sterigmate, sterigmata up to 5 µm long; up to 0.25 mm thick; hymenial surface basidiospores (Fig. 13) (16-) 19-24 × (8-) smooth, pinkish buff (near 7.5 YR 8/4); 10-12 µm distinctly pink in mass (spore 104 M. J. Larsen & R. L. Gilbertson

Figs. 2-17. Microscopical characteristics of species of Laeticorticium. Scale bars equal µm. Figs. 2-5. Laeticorticium appalachiense (from type). Fig. 2. Dendrohyphidia. Fig. 3. Probasidia. Fig. 4. Basidia. Fig. 5. Basidiospores. Figs. 6-9. Laeticorticium canfieldii (from type). Fig. 6. Dendro­ hyphidia. Fig. 7. Probasidia. Fig. 8. Basidia. Fig. 9. Basidiospores. Figs. 10-13. Laeticorticium durangense (from type). Fig. 10. Dendrohyphidia. Fig. 11. Probasidia. Fig. 12. Basidia. Fig. 13. Basidiospores. Figs. 14-17. Laeticorticium griseo-effusum (from type). Fig. 14. Dendrohyphidia. Fig. 15. Probasidia. Fig. 16. Basidia. Fig. 17. Basidiospores. Laeticorticium and related genera 105 print), hyaline under the microscope, broad tapered slightly towards the base, 4-sterig­ to narrowly ellipsoid. mate, sterigmata up to 10 µm long and 2-3 Laeticorticium durangense may be readily µm diam at the base; basidiospores (Fig. 17) diagnosed by its usual occurrence on pine cylindric to narrowly ellipsoid, bluntly cone epiphylls and by the size of its basi­ apiculate. hyaline, 19-23 × 8-10 µm. diospores. The diagnostic characters of this species are the thin, effused grayish white basi­ Specimens examined diocarps, and the cylindrical to narrowly MEXICO, STATE of DURANGO, On cones ellipsoid spores. and branches of Pinus ponderosa Laws., Cum­ mins, 13 × 1971 (CFMR FP 133141, holo­ Laeticorticium minnsiae (Jacks.) Donk, Fun­ type; isotype in ARIZ); on cones of P. gus 26:17. 1956. Aleurodiscus minnsiae Jacks., ponderosa, Cummins (CFMR FP 101516); Can. J. Res. (C)28:67. 1950. East of Chalco on Hwy 190, on cone epiphylls Basidiocarps biennial, developing in the of Pinus sp., Cain (TRTC 37132); near late summer or fall on underside of small Amecameca, base of Mt. Popocatepetl, on branches on which a sclerotial stage (Fig. 22) cone epiphylls of Pinus sp., Cain (TRTC appeared on the upperside earlier in the 37137); and on slopes of Mt. Popocatepetl, season, not maturing until the following spring on cone epiphylls of Pinus sp., Cain (TRTC or early summer, developing in small coales­ 37108). U.S.A., TEXAS. El Paso Quarantine cing patches up to 1 cm diam, adherent, but Station, on cone epiphylls of Pinus sp. (from tending to peel away from substratum in the Mexico), Smith, El Paso Quarantine Station mature stage when dried; hymenial surface no. 28510 (BPI, TRTC). cream white (near 10.0 YR 8/4), soft and very finely tomentose under a 25 × lens; Laeticorticium griseo-effusum Larsen & Gil­ margin abrupt. bertson, sp. nov. Etymology-From griseus (L., Subicular hyphae 2-5 µm diam, clamped, adj.) = gray + effusus (L., adj.) = effused. hyaline, thin- to moderately thick-walled, Basidiocarpis 0.2 mm crassis, effusis, with occasional branching; dendrohyphidia pruinosis, griseo-albis; hyphis 1.5-2 (-2.5) (Fig. 18) abundant, even in immature fruiting µm diam, fibulatis; probasidiis adsunt; basi­ bodies in which basidia or probasida are not diis 65-80 (-100) × 10-12 µm; basidiosporis yet discernible, 2-5 µm diam, often with 19-23 × 8-10 µm, cylindraceis vel cylin­ clamp connections, branched and conspicu­ draceo-ellipsoideis. ously so in some specimens; probasidia (Fig. Holotypus-U.S.A. ARIZONA. Coronado 19) appearing as variously shaped vesicular National Forest, Chiricahua Mts., Cochise bodies, abundant throughout tissue directly County, Turkey Creek, ad ramosa Pseud­ adjacent to the subiculum, these often bran­ otsuga menziesii (Mirb.) Franco, legit R. L. ched or variously contorted; mature basidia Gilbertson 10701, 18 VIII 1972 (CFMR); iso­ (Fig. 20) greatly elongated and contorted, typus in ARIZ. often branched, 100-130 × 8-10 µm, 4­ Basidiocarps apparently biennial, effused sterigmate, sterigmata 2-3 µm diam at the up to 4 × 2 cm, up to 0.2 mm thick, in patches, base and 8-10 µm long; basidiospores (Fig. pruinose; hymenial surface grayish white 21) 12-15 × 9-11 µm, broadly ellipsoid. (near 10.0 YR 8/2); subiculum grayish white; Sclerotial Stage (Fig. 22) - Cups laterally sterile margin narrow, farinaceous, concolor­ or basally attached on upper side of branches, ous with the hymenial surface. single or confluent and fused with adjacent Subicular hyphae thick-walled, hyaline, cups, 500-900 µm diam, white to pale buff, 1.5-2 (-2.5) µm diam, septate, clamped; sometimes cottony on outer surface; sclerotial dendrohyphidia (Fig. 14) not forming a well- bodies single, slightly darker than cup, spheri­ defined catahymenium, 1.5-2.5 µm diam, cal, slightly flattened apically, projecting sparingly septate, clamps present, sparingly hyphae giving a sparsely cottony appearance branched at the apex, associated with abun­ to the surface, 300-500 µm in diam. dant crystalline material; probasidia (Fig. 15) Hyphae of the cup tissue thin- to thick- subglobose to ovoid, 9-13 µm across; basidia walled, clamped, hyaline, 2-8 µm diam; (Fig. 16) 65-80 (-100) × 10-12 µm, sinuous, hyphae (Fig. 23) of the sclerotial body very

8 - Botany 106 M. J. Larsen & R. L. Gilbertson

Fig. 22. Laeticorticium minnsiae. Sclerotia-coiltaining cups on the upper side of a branch of Tsuga canadensis (× 13, from type). thick-walled in the interior portion, contorted ONTARIO. Woods east of Maple, on T. and breaking up into short segments, up to canadensis (L.) Carr., Jackson (TRTC 8232, 16 µm diam, with conspicuous swellings and BPI); Bell’s Lake, Parry Sound, on T. constrictions, thinner walled in tissue around canadensis, Jackson (TRTC 8233, BPI); the periphery. Sutton, on T. canadensis, Jackson (TRTC Basidiocarps first appear in the fall as 11700, BPI); woods near Holland River small, sterile patches on the underside of Marsh, on T. canadensis, Jackson, TYPE small branches bearing cups with sclerotial (TRTC 11131, BPI, NY); Chalk River, bodies on the upper surface. These small on T. canadensis, Jackson (TRTC 17493, patches show abundant well developed den­ NY); woods east of Maple, on T. cana­ drohyphidia of typical form although no sign densis, Jackson (TRTC 9835, NY); To­ of basidia in any stage of development can ronto, on T. canadensis, Jackson and Cain be found. Apparently the dendrohyphidia (TRTC 8231, NY); west of Aurora, on T. develop rapidly from the inception of the canadensis, Jackson (TRTC 13240, NY); Hol­ basidiocarp. This is well exemplified by speci­ land River Marsh, on T. canadensis, Jack­ men Hansbrough 176 (BPI). son (TRTC 12176, NY). QUEBEC. Mt. Bur- Laeticorticium minnsiae is the only known net, on T. canadensis, Jackson (TRTC 22948, species of Laeticorticium that possesses a NY). U.S.A. CALIFORNIA. Darlingtonia, means of asexual propagation. The sclerotial Del Norte County, on Pseudotsuga menziesii, stage is usually associated with the perfect Parks, 6947 (NY). MAINE. Brookton, on T. stage, and is a reliable diagnostic aid. canadensis, Eno (FP 88979, BPI); Orient, on T. canadensis, Eno & Hansbrough (FP 88986, Specimens examined BPI); Bar Harbor, on T. canadensis, Hans­ CANADA. BRITISH COLUMBIA. Cinema, brough (FP 93577, BPI); Dover-Foscroft, on on Tsuga heterophylla (Raf.) Sarg., Ziller, T. canadensis, Hansbrough & Eno (FP 88982, 23 VII 1949 (NY); D’Arcy, on Pinus pon­ BPI); Skowhegan, on T. canadensis, Eno (FP derosa Laws., Hansbrough 174 (NY). 88980, BPI). MICHIGAN. Keweenaw Point, Laeticorticium and related genera 107 on T. canadensis, Minns 281 (NY); NEW formed directly adjacent to subicular tissue, HAMPSHIRE. Waterville, on T. canadensis, globose to subglobose, often napiform, 12-18 Hansbrough 176 (BPI); Plainfield, on T. cana­ µm across; mature basidia (Fig. 26) 40-65 densis, Eno (FP 69972, BPI); Bottomless Pit, (-75) × 9-13 µm, sinuous-clavate, 4-sterig­ Hanover, on T. canadensis, Overholt 20462 mate, sterigmata up to 5 µm long; basidio­ (PAC); Intervale, on T. canadensis, Thaxter, spores (Fig. 27) 15-18 × 8-11 µm, obovate to 1 X 1901 (NY); Thornton, on T. canadensis, broadly ellipsoid. Hansbrough 177 (NY); Plainfield, on T. Laeticorticium mississippiense is separated canadensis, Eno (FP 69972, BPI). NEW from other species of the genus by its very YORK. King’s Ravine north of Frontenac thin and scanty basidiocarps, noticeably glob­ Point, Lake Cayuga, on T. canadensis, Jack­ oid probasidia, and compact subicular tissue. son, 13 X 1946 (NY); Eagle’s Nest Inlet, on Its spores are similar to those of L. canfieldii T. canadensis, Overholts 18946 (PAC); Lewis in size and shape. on T. canadensis, Povah, VIII 1920 (NY); Specimens examined Watkins Glen, on Picea?, Beach & Fairchild 4031 (BPI); Alexandria Bay, on T. canadensis, U.S.A. ARIZONA. Coronado National Eno & Hansbrough, 12 IX 1935 (BPI); Morish Forest, Santa Cruz County, Atascosa Mts., Center, on T. canadensis, Eno (FP 88979, Sycamore Canyon, on Quercus emoryi Torr., BPI). NORTH CAROLINA. Cranberry, on Canfield 72-162 (ARIZ, CFMR); Santa Cata­ T. canadensis, Thaxter, VII-VIII 1887 (NY). lina Mts., Pima County, on Juglans major OREGON. Rhododendron, on P. menziesii, (Torr.) Heller, Canfield 71-86 (ARIZ, Kimme & Childs (FP 68063, BPI); Rhodo­ CFMR); MISSISSIPPI. Stoneville, on hard­ dendron, on Pinus contorta Dougl., Hans­ wood (?Quercus ) on the ground, Lentz brough 31 III 1931 (BPI); Rhododendron, on (CFMR, FP 106848); on Cornus, Lentz P. menziesii, Hansbrough 175 (BPI). PENN­ (CFMR, FP 106807); on Morus, Lentz (holo­ SYLVANIA. Laurel Run, Huntingdon Coun­ type in BPI, FP 106664, and isotype in ty, on T. canadensis, Overholts & Vesta Green CFMR). 22819 (PAC); Lamar Gap, Clinton County, Laeticorticium pini (Jacks.) Donk, Fungus on T. canadensis, Overholts 22921 (PAC); 26:17. 1956. Aleurodiscus pini Jacks., Can. J. Stone Creek, Huntingdon County, on T. cana­ Res. (C)28:74. 1950. densis, Overholts 19734 (PAC); Ross Run, Basidiocarps annual (? biennial), usually Huntingdon County, on T. canadensis, Over­ consisting of thin, scattered patches on the holts 16885 (PAC); Laurel Run, Huntingdon underside of small branches, up to 200 µm County, on T. canadensis, Overholts 20207 thick, sometimes confluent to form a more (BPI). VERMONT. Bethel, on T. canadensis, extensive mat, not readily separable; hymenial Spaulding (FP 93265, BPI). surface pale buff (near 2.5 Y 8/4 and 10.0 YR 8/4), appearing finely tomentose under a Laeticorticium mississippiense Lentz, in Lar­ 25 × lens; subiculum pale buff, soft; margin sen & Gilbertson, Can. J. Bot. 52:688. 1974. fertile, abrupt, or thinning out and arachnoid, Basidiocarps apparently annual, resupinate, white. occurring in small patches which eventually Subicular hyphae 2-4 (-5.5) µm diam, coalesce, up to 0.2 mm thick, pruinose; fertile hyaline to pale yellowish brown, septate, area pale yellowish buff (near 2.5 Y 8/4), usually with clamps, with occasional branch­ hymenial surface smooth; subiculum obscure, ing, thin to moderately thick-walled; dendro­ apparently concolorous with to paler than the hyphidia (Fig. 28) abundant, clamped, some fertile area; margin narrow, pruinose, con­ much-branched, branches 1-2 µm diam; pro­ colorous with to paler than the fertile area. basidia (Fig. 29) terminal or intercalary, Subicular hyphae compact, 2-2.5 (-3) µm fusiform to spherical, often thick-walled, up diam, becoming 3-3.5 µm towards the hy­ to 10 µm diam; mature basidia (Fig. 30) 80­ menium, heavily incrusted with granular ma­ 100 × 7-8 (-9) µm, narrowly clavate, 4­ terial; dendrohyphidia (Fig. 24) arising from sterigmate, sterigmata up to 4.5 µm long; the same level as basidia, 2-4 µm diam at basidiospores (Fig. 31) 9-11 (-13) × 5-7.5 base, clamped, becoming extensively and very (-9) µm, ovoid to ellipsoid, somewhat flat­ intricately branched; probasidia (Fig. 25) tened on one side, with prominent apiculi. 108 M. J. Larsen & R. L. Gilbertson

Figs. 18-21; 23-31. Microscopical characteristics of species of Laeticorticium. Scale bars equal 10 µm. Figs. 18-21, 23. Lacticorticium minnsiae (from type). Fig. 18. Dendrohyphidia. Fig. 19. Probasidia. Fig. 20. Basidia. Fig. 21. Basidiospores. Fig. 23. Thick-walled hyphae of sclerotial body. Figs. 24-27. Laeticorticium mississippiense (from type). Fig. 24. Dendrohyphidia. Fig. 25. Probasidia. Fig. 26. Basidia. Fig. 27. Basidiospores. Figs. 28-31. Laeticorticium pini (from type). Fig. 28. Dendrohyphidia. Fig. 29. Probasidia. Fig. 30. Basidia. Fig. 31. Basidiospores. Laeticorticium and related genera 109

Laeticorticium pini may be separated from especially conspicuous in immature basidio­ other species in the genus by its occurrence carps, intricately branched, often clamped, on Pinus strobus and size of basidiospores main branches 2-3 µm diam; probasidia (Fig. (9-11 (-13) × 5-7.5 (-9) µm). The fungus is 33) abundant in late fall and early spring, probably distributed throughout the natural at first thick-walled, spherical to elongated, range of P. strobus. some forked or lobed, elongating in late spring and early summer; mature basidia (Fig. 34) Specimens examined 70-100 × 7-10 µm, often sinuous-clavate, CANADA, ONTARIO. Woods north of Sum­ 4-sterigmate, sterigmata 2-3 µm diam at the mit Golf Club, Richmond Hill. on P. strobus, base, up to 8 µm long; basidiospores (Fig. 35) Jackson (TRTC 11640, BPI); also (TRTC distinctly apiculate, narrowly ellipsoid, most­ 8230, SYRF, BPI); Munising, Simcoe County, ly flattened on one side, 17-24 × 8-12 µm. on P. strobus, Cain, (TRTC 32472. BPI); We have referred basidiocarps of what ap­ Midhurst, Simcoe County, on P. strobus, Cain, pear to represent several species to the ‘L. (TRTC 30075, BPI); Maple, York County, roseum -complex.’ This complex is charac­ on P. strobus, Linder, 5 V 1936 (TRTC, BPI); terized by hyphae with clamp connections, Algonquin Park, on P. strobus, Jackson deeply imbedded probasidia, a pink to ochra­ (TRTC 17631, BPI); Constance Bay, NW of ceous hymenial surface, and large ovate to Ottawa, on P. strobus, Jackson, 30 VI 1938 ellipsoid basidiospores that are pink to pink­ (TRTC, BPI); Oakland Swamp, Brant County, ish red in mass. Numerous specimens from on P. strobus, Cain (TRTC 16494, BPI); the Mississippi Valley and southwestern, Richmond Hill, on P. strobus, Jackson (TRTC northwestern, and north central United States 13241, BPI). U.S.A., NEW HAMPSHIRE. have been placed in this complex. However, Jeffrey on P. strobus, Darker (FP 6822, BPI). we are now able to state with some certainty NEW YORK. Warrensburg, on P. strobus, the criteria necessary to delimit the species Gilbertson 5806, 5811 (SYRF); Ithaca, Coy that are placed here. We have arrived at the Glen, on P. strobus, Nobles (DAOM 31466, following: SYRF); Minnewaska, on fallen pine limbs, (1) Spore shape and dimension must be Peck (MO 55980, BPI). obtained from freshly discharged basi­ diospores. Laeticorticium roseum (Pers. per Fr.) Donk, (2) The type of mating system must be as­ Fungus 26:17. 1956. Corticium roseum Pers., certained. Dispos. Meth. Fung., p. 31. 1797 (devalidated (3) Interfertility tests must be employed name). Thelephora (Himantia) rosea (Pers.) among those similar fungal populations per Fr., Syst. Mycol. 1:451. 1821. Lyomyces with the same, overlapping, or disparate roseus (Pers. per Fr.) Karst., Bidr. Kann, Finl. distributions. Nat. Folk. 37:153. 1882. Hypochnus roseus (4) Degree of host specificity must be re­ (Pers. per Fr.) Schroet., in Cohn, Krypt.-F1. cognized. Schles. 3(1):417. 1889. Peniophora rosea (Pers. At present we are reasonably satisfied that per Fr.) Massee, auct., J. Linn. Soc. (Bot.) L. roseum of Persoon is homothallic and is 25:146. 1889-1890 [1890]. the species he recorded from Populus sp. and Corticium roseolum Massee, J. Linn. Soc. Salix sp. It is also our contention that this (Bot.) 27:140. 1890-1891 [1891]. fungus is equivalent to L. roseum-group A Basidiocarps biennial, appearing determi­ of Boidin et al. (1968). nant on branches of standing Populus sp. and Salix sp. and somewhat aleurodiscoid, usually Specimens examined adherent, sometimes separable, soft, some­ CANADA, ONTARIO. Sault Ste. Marie times cracking on drying and exposing the District, Kirkwood Management Area north white subiculum; hymenial surface cream of Thessalon, on Populus tremuloides Michx., white to dull pinkish buff (7.5 YR 8/4); sterile Larsen 3504 (CFMR, SSMF 695-4580); Sault margin narrow and abrupt. Ste. Marie, 4th line and Old Goulais Bay Subicular hyphae 2.5-5 µm diam, becoming Road, on P. tremuloides, Larsen 3508 (CFMR, thick-walled, septate, clamped, branching fre­ SSMF 695-4581); St. Joe’s Island, on P. tre­ quently; dendrohyphidia (Fig. 32) abundant, muloides, Trieselmann (CFMR. FP 133130). 110 M. J. Larsen & R. L. Gilbertson

FRANCE. Drancy (Seine St. Denise), on 4. Basidiocarp tissue, in part, amyloid in Salix sp., Hespléde (Boidin herb. 5242, LY); Melzer’s reagent ...... D. piceinum Prés de Nivolet (Ain), Salix cinerea L., Ber­ 4. Basidiocarp tissue negative in Melzer’s thier (Boidin herb. 5248, LY); Ermenonville reagent ...... 5 (Oise), Salix sp., Hespléde (Boidin herb. 5774, 5. Basidiospores subglobose to broadly LY). U.S.A., NEW YORK. Tully, Heiberg ovoid, 4-6.5 × 3-5 µm; usually on Memorial Forest, on P. tremuloides, Gilbert- Fraxinus nigra in northeastern North son 5802 (CFMR). WISCONSIN. Cambridge, America ...... D. violaceum on P. tremuloides, Larsen (CFMR, FP 133144); 5. Basidiospores 6-10 × 3.5-6 µm ...... 6 Nicolet National Forest, near Whitefish Lake, 6. Basidiocarps with conspicuous white on P. tremuloides, Larsen (CFMR, FP 133166), mycelial strands; basidiospores 6-10 × and at junction of Forest Service roads 2114 3.5-4.5 µm ...... D. lundellii and 2118, on P. tremuloides, Larsen (CFMR, 6. Basidiocarps without mycelial strands; FP 133177). basidiospores 6-9 × 1-6 µm ...... D. polygonioides THE GENUS DENDROCORTICIUM Dendrocorticium jonides (Bres. in Brinkm.) Dendrocorticium Larsen & Gilbertson, Norw. Larsen & Gilbertson, Norw. J. Bot. 21:225. J. Bot. 21:225. 1974. Laeticorticium Donk 1974. Corticium jonides Bres. in Brinkm., sect. Laeticorticium Parm., pro parte, Consp. Jahresber. Westfal. Prov. Ver. Wissen. und Syst. Cortic., p. 151. 1968. Nomenclatural Kunst 26:128. 1898. Aleurodiscus jonides type species Dendrocorticium polygonioides (Bres. in Brinkm.) Bourd. & Galz., Bull. Soc. (Karst.) Larsen & Gilbertson. Mycol. France 28:353. 1912. Laeticorticium Basidiocarps annual, effused; hymenial jonides (Bres. in Brinkm.) Donk, Fungus surface smooth; hyphal system monomitic; 26:17. 1956. subicular hyphae usually septate with clamp Corticium jonides var. dealbatum Bres. in connections and with some wall thickening; Brinkm., Jahresber. Westfal. Prov. Ver. Wis­ dendrohyphidia present, with or without a sen. und Kunst 26:128. 1898. well defined catahymenium; probasidia pre­ Basidiocarps apparently biennial, curling sent and formed in the subhymenium; mature away from the substratum in some portions, basidia formed by intrusive metabasidial effused up to 5 × 3 cm, up to 0.3 mm thick, growth, up to 75 µm long, frequently project­ firm, mostly adherent or separable in small ing noticeably above the catahymenium; basi­ pieces, somewhat waxy, cracking slightly on diospores rarely exceeding 12 µm in length, drying; hymenial surface smooth, slightly subglobose, ellipsoid, or broadly ovoid, powdery or minutely pulverulent under a smooth, hyaline, thin-walled, negative in Mel­ 10 × lens, pale to dark buff (near 10.0 YR zer’s reagent, acyanophilous. Spore prints 8/6 and 10.0 YR 8/4); subiculum and sub­ usually white, sometimes pale red. hymenial tissue concolorous to somewhat paler than the hymenial region; sterile margin ir­ KEY TO THE SPECIES OF regular in outline, narrow, almost white to DENDROCORTICIUM concolorous with the fertile portion, villose. 1. Basidiospores usually more than 9 µm Subicular hyphae 2-3.5 µm diam, parallel long ...... 2 to the substratum, compact, clamped, hyaline, 1. Basidiospores usually less than 9 µm somewhat thick-walled, walls appearing gela­ long ...... 4 tinous in KOH; subhymenial hyphae 2.5-3.5 2. Basidia 40-70 µm long ...... 3 µm diam, septate, clamped, hyaline, thin- 2. Basidia 75-100 µm long ...... D. jonides walled; other hyphae 3-5 µm diam, clamped, 3. Basidiocarps membranous and separ­ with rare branching, vertically oriented, giv­ able, up to 0.5 mm thick, not reflexed; ing rise to hymenial dendrohyphidia (Fig. buff to yellowish brown D. lilacinoroseum 36); probasidia (Fig. 37) napiform, becoming 3. Basidiocarps often firm and waxy, not elongated; mature basidia (Fig. 38) 75-79 readily separable, up to 1.5 mm thick, (-110) × 5-8 µm, clavate, with constrictions often reflexed; in part usually some and swellings, 4-sterigmate, sterigmata up to shade of purple or violet D. roseocarneum 6 µm long; basidiospores (Fig. 39) 8.5-10 Laeticorticium and related genera 111

(-12) × 6.5-7 µm, conspicuously apiculate, to yellowish brown (near 7.5 YR 8/4); subi­ broadly ellipsoid to ovoid. culum white; sterile margin narrow, white, This species has been widely treated in the arachnoid. European literature and is reported from Subicular hyphae hyaline, moderately thick- North America by Moffatt (1909) as Corti­ walled, clamped, 2.5-3.5 (-4) µm diam; den­ cium jonoides Bres., but this report is probab­ drohyphidia (Fig. 40) abundant but apparent­ ly based on a specimen of D. roseocarneum. ly not forming an obvious and distinct cata­ We have seen no North American specimens hymenium, coarsely branched and lobed, of D. jonides. clamped, sometimes lightly incrusted with In the original description of the species, granular material, 3-4 µm diam; probasidia the specific epithet was spelled ‘jonides’, and (Fig. 4 1) frequently napiform; basidia (Fig. this same orthography is followed in Brink­ 42) (40-) 60-70 × 6-8 µm, long clavate, mann’s exsiccati. However, Pilát (1926), Bour­ sometimes tortuous and constricted and some­ dot & Galzin (1928). Litschauer (1944), and what swollen, 4-sterigmate, sterigmata up to Boidin (1971) have spelled the epithet as 5 µm long; basidiospores (Fig. 43) 9-11 (-12) ‘ionides’. In Brinkmann’s diagnosis the color × 4-6.5 µm, ellipsoid, blunt-apiculate. of basidiocarps is given as ‘lilacino-amethys­ This species is well characterized by size of teum vel isabellino-testaceum.’ The prefix spores, and size of soft, separable, fruiting ‘ion-’ (Gr.) in the word ‘ionides’ means violet bodies. The spores resemble those of L. roseum colored. We consider Brinkmann’s name, in shape, but in the latter they are much therefore, as one containing questionable larger. orthography, but are reluctant to adopt a change involving the initial letter of the Specimens examined epithet (see Article 73, Note 2 of the Code). TUNISIA. El Fedja, on oak, Patouillard, We recommend the continued use of ‘jonides’. January 1893 (holotype in Patouillard herb., FH). Specimens examined GERMANY. Lengerich, an Rinde und Holz Dendrocorticium lundellii (J. Erikss.) Larsen von Fagus sp., Winter 1899/1900; no. 6 in & Gilbertson, Norw. J. Bot. 21:225. 1974. Brinkmann, Vorarbeiten zu einer Pilzflora Laeticorticium lundellii J. Erikss., Symb. Bot. Westfalens (type of C. jonides); Lengerich, Upsal. 16:(1) 74. 1958. an Rinde von Salix sp., Winter, 1899-1900; Basidiocarps effused, up to 0.5 mm thick, no. 7 in Brinkmann, Vorarbeiten zu einer readily separable from substratum; hymenial Pilzflora Westfalens (type of C. jonides var. surface pale buff (near 2.5 Y 8/2), in some dealbatum); Lengerich, in cortice Salicis, areas appearing reticulate, with white my­ Brinkmann, I 1898 (TRTC ex S); Lengerich, celial strands and thicker pink rhizomorphs on Fagus sp., Brinkmann, I 1898 (TRTC ex visible in the underlying subiculum, in better S); Lengerich, ad corticem Fagi, Brinkmann, developed areas with an unbroken, continuous IV 1897 (TRTC ex S); Tirol, Brandenberger­ surface, farinaceous under 10 × lens; margin tal bei Brixlegg, Litschauer, 10 X 1920 (TRTC strikingly fimbriate with the white, feathery ex S, herb. Litschauer). SWEDEN. Öland; mycelial strands extending out up to 5 mm Persnäs parish, Stenninge, on Rosa sp., Nann­ beyond the fertile area, a few thicker, pink feldt, 20 VII 1953 (TRTC ex S, Flora Sue­ rhizomorphs also present; subiculum soft, cica). white, very thin. Subicular hyphae (Fig. 44) 2-4 µm diam, Dendrocorticium lilacinoroseum (Pat.) Larsen hyaline, thin-walled, clamped, with scattered & Gilbertson, Norw. J. Bot. 21:225. 1974. incrustation, multiple clamps frequent; den­ Hypochnus lilacinoroseus Pat., Catal. Rais­ drohyphidia (Fig. 45) numerous, up to 2.5 soné Plant. Cellul. Tunis., p. 62. 1897. µm diam, thin-walled, some with rather ex­ Basidiocarps annual, up to 0.5 mm thick, tensive and irregular branching, others with effused in small patches up to 5 mm diam, little or no branching but contorted; pro­ often anastomosing and becoming laterally basidia (Fig. 46) somewhat napiform, wall confluent, membranous, somewhat separable; thickening infrequent; basidia (Fig. 47) nar­ hymenial surface smooth, buff or pinkish buff rowly clavate, 30-50 × 4-6 µm, 4-sterigmate, 112 M. J. Larsen & R. L. Gilbertson

Figs. 32-48. Microscopical characteristics of species of Laeticorticium and Dendrocorticium. Scale bars equal 10 µm. Figs. 32-35. Laeticorticium roseum (from MJL 3504). Fig. 32. Dendrohyphidia. Fig. 33. Probasidia. Fig. 34. Basidia. Fig. 35. Basidiospores. Figs. 36-39. Dendrocorticium jonides (from type). Fig. 36. Dendrohyphidia. Fig. 37. Probasidia. Fig. 98. Basidia. Fig. 39. Basidiospores. Figs. 40-43. Dendrocorticium lilacinoroseum (from type). Fig. 40. Dendro­ hyphidia. Fig. 41. Probasidia. Fig. 42. Basidia. Fig. 43. Basidiospores. Figs. 44-48. Dendro­ corticium lundellii (from RLG 4757). Fig. 44. Subicular hyphae. Fig. 45. Dendrohyphidia. Fig. 46. Probasidia. Fig. 47. Basidia. Fig. 48. Basidiospores. Laeticorticium and related genera 113

sterigmata slender, curved, up to 5 µm long; branching frequently; other hyphae 1-2 µm basidiospores (Fig. 48) 6-10 X 3.5-4.5 µm, diam, branching extensively and occurring with a large apiculus, ovoid to oblong. throughout the subiculum and subhymenium, In the original description Eriksson gives amyloid in Melzer’s reagent; dendrohyphidia the color of the fresh basidiocarps as ‘Grena­ (Fig. 49) abundant (catahymenial development dine Pink’ or ‘Venetian Pink’. He also reports discontinuous), arising from tissue directly ad­ the spore print as being pale red. Basidio­ jacent to the subiculum, degree of branching carps of D. lundellii are distinguished by their at apices variable, 2-3 µm diam, clamped; pale pink color and the conspicuous white sterile elements (Fig. 50) in the hymenium mycelial strands at the margin. subulate to obclavate, often tortuous and con­ stricted, up to 40 µm long, not projecting Specimens examined above the hymenium; probasidia (Fig. 51) CANADA, ALBERTA. Whitecourt, on Po­ not readily discernible; mature basidia (Fig. pulus balsamifera L., Gilbertson 3439 (SYRF); 52) 45-55 × 7-8 µm, often with a median Whitecourt, on Picea glauca (Moench) Voss, swelling (? probasidum), upper part of the Gilbertson 6652 (SYRF); Athabasca River, basidium approximately cylindrical, 4-sterig­ Jasper National Park, on Pinus contorta mate, sterigmata up to 8 µm long; basidio­ Dougl., Gilbertson 4757 (SYRF); YUKON spores (Fig. 53) 7.5-8 × 5-6 µm, broadly TERRITORY. Mile 1005, Alcan Highway, on ellipsoid to subglobose, hyaline. Salix sp., Gilbertson 8804 (ARIZ). SWEDEN. Basidial development of D. piceinum is Uppland, Uppsala, 1 km. S of Hägaborg, somewhat atypical for the genus. Basidial Nilsson (SYRF ex herb. John Eriksson 2012); initials are positioned in the subhymenium at Uppland, Bondkyrka parish, near Uppsala, on the base of the branching portion of dendro­ dead stems of Rubus sp., Lundell, Fungi hyphidia, and in this respect can be likened Suecici 189 (TRTC); Hälsingland, Harmän­ to Dentocorticium. The basidial ontogeny in ger parish, Stränsbruk, on coniferous wood, the material studied suggests, however, that Eriksson 90 (TRTC); Djurö, Runmarö, Vägen probasidial and metabasidial stages are pre­ Södersunda-Skogsberga ödetorp, vid första sent, but the typical form is not as accentuated kalkhällen, Eriksson & Haglund, 3 XI 1949 as it is in other species. This and the shape (TRTC ex S). and size of the spores suggest the affinity with Dendrocorticium. Dendrocorticium piceinum Lemke, sp. nov. Etymology-from Picea. Other specimens examined Basidiocarpis effusis, albis e alboluteis e CANADA, ONTARIO. Algoma District, luteis; hyphis subiculis et subhymeniis amy­ Little White River, on Picea sp., Cain (TRTC loideis in IKI; hyphis sterilibus in hymeniis 32513, NO, CFMR); U.S.A., SOUTH CARO­ subulatis vel obclavatis; basidiosporis 7.5-8 × LINA. Sand Hills State Forest, Cheraw, on 5-6 µm, late ellipsoideis e subglobosis. Taxodium distichum (L.) Rich, Hodges, 25 IX Holotypus-Canada, Ontario, Kenora Dis­ 1960 (CFMR). trict, N. Vermillion Bay, ad lignum Picea sp., leg. R. F. Cain, 6 V 1956 (TRTC 33417); Dendrocorticium Polygonioides (Karst.) Lar­ isotypi in herb. NO, J. Eriksson, BPI, CFMR, sen & Gilbertson, Norw. J. Bot. 21:225. DAOM, FH, K, L, LE et NY. 1974. Corticium Polygonioides Karst., Medd. Basidiocarps apparently annual, effused up Soc. Fauna Fl. Fenn. 6:12. 1881. Xerocarpus to 8 × 3 cm, occurring in small patches which polygonioides (Karst) Karst., Rev. Mycol. eventually coalesce, firm, separable, up to 3:22. 1881. Xerocarpus polygonium var. poly­ 0.8 mm thick; hymenial surface smooth, gonioides (Karst.) Karst., Acta Soc. Fauna Fl. pruinose, cracking upon drying, pale buff to Fenn. 2:38. 1881. Lyomyces polygonioides pale yellowish buff (near 2.5 YR 814 and 2.5 (Karst.) Karst., Finska Vet. soc. Bidr. Nat. YR 8/6); subiculum white; margin pale yel­ Folk 58:419. 1889. Laeticorticium polygoni­ low to white, abrupt to becoming villose or oides (Karst.) Donk, Fungus 26:17. 1956. pruinose. Basidiocarps annual or (?) biennial, re­ Subicular hyphae 2-4 µm diam, septate, supinate, effused up to 9 × 5 cm, up to 1.0 clamped, hyaline, wall thickening apparent, mm thick, mostly dark buff to medium brown 114 M. J. Larsen & R. L. Gilbertson

Figs. 49-65. Microscopial characteristics of species of Dendrocorticium. Scale bars equal 10 µm. Figs. 49-53. Dendrocorticium piceinum (from type). Fig. 49. Dendrohyphidia. Fig. 50. Sterile hymenia1 elements. Fig. 51. Probasidia. Fig. 52. Basidia. Fig. 53. Basidiospores. Figs. 54-57. Dendrocorticium polygonioides (from Parmasto 66). Fig. 54. Dendrohyphidia. Fig. 55. Probasidia. Fig. 56. Basidia. Fig. 57. Basidiospores. Figs. 58-61, Dendrocorticium roseocarneum (from JLL 3477). Fig. 58. Dendrohyphidia. Fig. 59. Probasidia. Fig. 60. Basidia. Fig. 61. Basidiospores. Figs. 62-65. Dendrocorticium violaceum (from type). Fig. 62. Dendrohyphidia. Fig. 63. Probasidia. Fig. 64. Basidia. Fig. 65. Basidiospores. Laeticorticium and related genera 115

(near 7.5 YR 7/2, 7/4, and 8/4; and 10.0 YR Schrift 1:107. 1822 (basionym). Stereum roseo­ 7/8), cracking extensively on drying and ex­ carneum (Schw.) Fr., Acta Soc. Sci. Upsala posing fibrous subiculum, velvety or finely (III) 1:112. 1851. Laxitextum roseocarneum tomentose; subiculum soft, white next to the (Schw.) Lentz, Agric. Monograph No. 24, substratum, becoming increasingly buff co­ U.S.D.A., p. 22. 1955. Laeticorticium roseo­ lored towards the hymenial region; margin carneum (Schw.) Boid., Bull. Soc. Mycol. cottony, villose to fimbriate, usually paler France 74:479. 1958. than older parts, but some parts becoming Corticium lilacinofuscum Berk. & Curt., dark buff. Grevillea 1:180. 1873. Subicular hyphae 2-4.5 µm diam, the dia­ Corticium subrepandum Berk. & Cke., Gre­ meter decreasing with subsequent hyphal villea 6:81. 1878. branching to 1-1.5 µm diam, septate, clamped, Stereum sendaiense Lloyd, Mycol. Writ. 5, hyaline; dendrohyphidia (Fig. 54) arising Mycol. Notes 48:680. 1917. from upright hyphae in the subiculum, mostly Basidiocarps annual or biennial, apparent­ under 40 µm long, 1-2.5 µm diam, clamped; ly not maturing at the end of first growing probasidia (Fig. 55) usually napiform; mature season, effused or narrowly reflexed, often basidia (Fig. 56) 50-60 × 5-7 (-8.5) µm, firm and waxy, not readily separable, occur­ tortuous, hyaline, 4-sterigmate, sterigmata up ring in small patches and becoming confluent, to 7 µm long; basidiospores (Fig. 57) 6-9 × frequently covering large substrate surfaces, 4-6 µm, prominently apiculate, ovoid, some­ up to 1.5 mm thick; hymenial surface smooth, times appearing flattened on one side. color variable in dried specimens, dark purp­ Dendrocorticium polygonioides is readily lish brown to pale violet buff (near 5.0 YR characterized by the extensively cracked basi­ 614, 10.0 YR 514, 5.0 YR 712, 5.0 YR 3/4, diocarps, which are dark buff to medium 7.5 YR 614) to pale brownish yellow (near brown, and ovoid basidiospores. Litschauer 10.0 YR 8/6), cracking on drying and expos­ (1944) has indicated synonymy of this species ing a pale brown to pale buff subhymenium with D. jonides. and a white subiculum; sterile margin thin, abrupt, pruinose to fibrillose. Specimens examined Subicular hyphae 2-3.5 (-4) µm diam, sep­ AUSTRIA. Innsbruck, on Fagus sp., Lit­ tate, clamped, hyaline, with some wall thick­ schauer 25 (TRTC ex herb. Litschauer); Tirol, ening; dendrohyphidia (Fig. 58) abundant near Seefild, on Fagus sp., Litschauer, 25* and usually forming a distinct catahymenium, (TRTC ex herb. Litschauer). ESTONICA 2-3.5 µm diam, septate, clamped, hyaline to RPSS. District Rakvere, Porkuni, ad truncum pale brown; probasidia (Fig. 59) not usually Coryli sp. emortuum in piceeto, Parmasto (66, discernible, but typical when present; mature Corticiaceae URSS. I.), 2 X 1956 (BPI). basidia (Fig. 60) 45-60 × 7-9 µm, often FINLAND. Mustiala, on Salix sp., Karsten, with a noticeable distension 15-20 µm above X 1881 (TRTC ex S ex herb. Sydow. Raben­ the basal septum, 4-sterigmate, sterigmata up horst-Winter Fungi Europaei 2821), and on to 5 µm long; basidiospores (Fig. 61) 8-12 × angiospermous wood, Karsten (TRTC ex S 4-6 µm, ovoid to broadly ellipsoid. ex H). ITALY. [Trento], on angiospermous Dendrocorticium roseocarneum is well cha­ wood, Bresadola, XI 1893 (TRTC ex S). racterized by the color of the hymenial sur­ NORWAY. Kristiania, auf Laubholz-rinde, face, size of spores, stratification of tissue in Egeland, 7 XI 1909 (TRTC ex S). SWEDEN. basidiocarps, and its apparent restriction to Uppland, Uppsala by Hägeborg, on decaying angiospermous substrate. It is widely dis­ fence, Melderis & Eriksson 1301 (DAOM tributed in eastern North America, reported 69161); Uppland, Hägeborg, on P. tremula, from Japan as Stereum sendaiense Lloyd, and Melderis (DAOM 69162); Åsele Lappmark: not yet known from Europe. Burt (1920) re­ Dorotea Parish, on Salix sp., B. & J. Eriksson ported S. sendaiense as a synonym of D. roseo­ 3524 (DAOM 69163). carneum, and cites a specimen (G. O. Malme 75) from Brazil. We have not, however, seen Dendrocorticium roseocarneum (Schw.) Lar­ the Brazilian collection. Lentz (1955) also sen & Gilbertson, comb. nov. Thelephora notes that it is reported from China. roseocarnea Schw., Naturf. Gesel. Leipz. Burt (1920) cites collections from the fol- 116 M. J. Larsen & R. L. Gilbertson lowing stations in states other than those which eventually coalesce, brittle, often crack­ given below: Indiana, Massachusetts, Michi­ ing extensively upon drying; fertile area pale gan, New Jersey, Virginia, and West Vir­ lilac-brown (near 2.5 Y 814 and 10.0 YR 814); ginia. hymenial surface smooth; subiculum white; sterile margin up to 6 mm wide or absent, Specimens examined yellowish tan. CANADA. NEW BRUNSWICK. Fredrick­ Subicular hyphae 1.5-3.5 µm diam, com­ ton, New Brunswick Forest, on Acer sp., pactly arranged and difficult to separate, Pongress 4321 (DAOM 99575). NOVA SCO- clamped: dendrohyphidia (Fig. 62) 2-3 (-4) TIA, Kentville, on Fagus sp., Harrison µm diam, clamped near point of origin, arising (DAOM F 5461); Ravine, on Quercus sp., from hyphae directly adjacent to subicular Harrison 3050 (DAOM 99574). ONTARIO. tissue, forming a discontinous catahymenium; London, on hardwood, Dearness 9451 (BPI, probasidia (Fig. 63) napiform to short clavi­ MBG 1425 1); Petawawa Forest Experiment pedunculate; basidia (Fig. 64) 30-45 × 4-6 Station, on Acer sp., Eriksson 8901 (DAOM µm, somewhat tortuous and with median 141288). JAPAN. Sendai, on Fraxinus sp., swelling, 4-sterigmate, sterigmata up to 5 µm Yasuda, 17 X 1918 (BPI). SIBERIA. U.R.S.S.: long: basidiospores (Fig. 65) 4-6.5 × 3-5 µm, oriens extremis, regio Chabarovsk, distr. Lazo, subglobose to broadly ovoid, hyaline. on Corylus sp., Parmasto 14170 (LY 4326, Dendrocorticium violaceurn is well charac­ CFMR). U.S.A., CONNECTICUT. North terized by its small spores (4-6.5 × 3-5 µm). Bloomfield, on Acer rubrum L., Eno (BPI FP Though we have not seen fresh specimens 81375, TRTC). NEW HAMPSHIRE. North of this fungus, it is apparent, from the appli­ Conway, on Acer sp., Overholts 5161 (BPI). cation of the name by H. S. Jackson and NEW YORK. Brookton, on hardwood, Muen­ from annotations (dealing with the fresh con­ scher 215 (BPI); Newcomb, on Fagus grandi­ dition) on a few collections, that the color of folia Ehrh., Lowe 3477 (SYRF). NORTH basidiocarps is frequently lilac to violet co­ CAROLINA. Salem, on hardwood, Schwein­ lored when encountered in the field. The itz (as Thelephora anthocroa in PH). PENN­ color fades noticeably upon drying and with SYLVANIA. Spruce Creek, on hardwood, subsequent herbarium storage. Faull (TRTC 312, BPI). WISCONSIN. As indicated by annotations on the packet Oneida County, Kemp Biological Station, of the type, portions of the specimen were Minocqua, on hardwood, Lombard & Payne sent to NO and Dr. J. Eriksson in Sweden. (CFMR FP 101403). VERMONT. Burlington, These portions, if still extant, should be con­ on Alnus rugosa (DuRoi) Spring., Spaulding sidered isotypic. (BPI FP 43994). Based on distribution data that are avail­ able, D. violaceum is apparently confined to Dendrocorticium violaceurn Jacks., sp. nov. eastern Canada in the Great Lakes-St. Law­ Etymology-From violaceus (L., adj.) = violet rence and Acadian Forest Regions (Halliday colored. 1937),and occurs primarily on Fraxinus nigra. Basidiocarpis effusis, rimosescenti, area fe­ It is associated with a white rot. cunda pallidolilacina vel ochracea (in horto sicco); hymenio superficie laevi; margine Additional specimens examined pallido-luteo; hyphis subiculis 1.5-3.5 µm, CANADA, NOVA SCOTIA. Anna County, fibulatis, compactis; probasidiis adsunt; basi­ Melvern Sq. Vault, on Alnus, Harrison 4276 diis 30-45 × 4-6 µm; basidiospores 4-6.5 and 4277 (DAOM 99462 and 99463, respec­ × 3-5 µm, subglobosis vel late ovoideis. tively); Kings County, Cape Split, on Alnus Holotypus-Canada, Ontario, Lake Tima­ sp., Harrison 4275 (DAOM 99461). ON­ gami, Bear Island, ad ligna Fraxinus nigra TARIO. Lake Timagami, on Acer saccharum Marsh., legit. H. S. Jackson 2 IX 1946, Marsh., Jackson (TRTC 11621); Bella TRTC 21116, et isotypi in CFMR, NO, et Lake, on Betula alleghaniensis Britt., Jackson herb. J. Eriksson. (TRTC 23446); Lake Timagami, on Fraxinus Basidiocarps annual, effused, margin fre­ nigra, Jackson (TRTC 11937, TRTC 11619, quently curling away from the substratum, TRTC 11620, TRTC 11618, TRTC 20042, up to 0.3 mm thick, occurring in patches TRTC 13306, and TRTC 13331); Lake Tima- Laeticorticium and related genera 117 gami, on Fraxinus sp., Jackson (TRTC 21116 ing; dendrohyphidia present, with or without and TRTC 17964); Petawawa, on Fraxinus a distinct and well defined catahymenium; sp., Jackson (TRTC 18045): S. Aurora, on probasidia absent; basidia clavate, 4-sterig­ Fraxinus sp., Jackson (TRTC 5457): Chalk mate, 30-.50 µm long; basidiospores rarely River, Cory Lake, on Fraxinus sp., Jackson exceeding 4 µm in diameter, ellipsoid to cy­ (TRTC 18035); Bella Lake. on Fraxinus sp., lindrical, sometimes allantoid, smooth, hya­ Jackson (TRTC 23176); Lake Timagami, line, negative in Melzer’s reagent, acyano­ Kokoko Bay, on Picea, Biggs (TRTC 10458); philous. Beaverton, on Populus sp., Jackson (TRTC 20596); Lake Timagami. Bear Island, on KEY TO THE SPECIES OF Prunus sp., Jackson (TRTC 17946). QUEBEC. DENTOCORTICIUM Gatineau Park, King Mountain, Black Lake, 1. Basidiospores 5-6 × 2-2.5 µm ...... on hardwood, Weresub, 62-42B (DAOM ...... D. ussuricum 73601). 1. Basidiospores 6-10 × 2.5-4 µm ...... 2 2. Basidiospores allantoid . . D. sulphurellum THE GENUS DENTOCORTICIUM 2. Basidiospores cylindrical to ellipsoid . . Dentocorticium (Parm.) Larsen & Gilbertson, ...... D. brasiliense Norw. J. Bot. 21:225. 1974. Laeticorticium Donk sect. Dentocorticium Parm., Consp. Dentocorticium brasiliense Larsen & Gilbert- Syst. Cortic., p. 151. 1968. Nomenclatural son, sp. nov. Etymology-From brasil (Brazil, type species Dentocorticium ussuricum (Parm.) South America) + -ense (L., suff. indic. Larsen & Gilbertson. origin) = brasiliense. Basidiocarps annual, effused; hymenial sur­ Basidiocarpa effuso, rimosescenti; area fe­ face smooth and undulating or dentate; hyphal cunda brunneopurpurascenti; hymenio super­ system monomitic or dimitic; subicular hyphae ficie laevi; hyphis subiculis brunneis, 3-5 (-6) usually clamped and with some wall thicken­ µm diam, fibulatis; hyphis fasciculis adsunt; 118 M. J. Larsen & R. L. Gilbertson probasidiis nullis; basidiis 30-40 (-45) × fissured, exposing a bistratose subhymenial 4-6 µm, longoclavatis; basidiosporis 6-10 × tissue; hymenial surface smooth, dark brown­ 2.5-4 µm, cylindricis, cylindrico-ellipsoideis ish purple (near 5.0 YR 3/2), tissue below the vel ellipsoideis, hyalinis. hymenium of two distinct layers, a pale pink­ Holotypus-Brasilia, ad ligna angiosperma, ish buff subhymenial zone above a dark brown (?) Rio Grande du Sul, legit. J. Kick, 1936 subicular layer of loosely interwoven hyphae; (FH, nominato ‘Merulius patellaeformis B. & sterile margin up to 2 mm wide, pale pinkish C.’). buff, surface tomentose, matted, edge fim­ Basidiocarp (Fig. 66) annual, effused up to briate. 6 × 2 cm, up to 0.5 mm thick, adherent, Hyphal system monomitic: subicular hyphae cracking on drying and becoming deeply 3-5 (-6) µm, thick-walled, yellowish brown,

Figs. 67-79. Microscopical characteristics of species of Dentocorticium and Laeticorticium. Scale bars equal 10 µm. Figs. 67-70. Dentocorticium brasiliense (from type). Fig. 67. Dendrohyphidia. Fig. 68. Thick-walled vesicular structures. Fig. 69. Basidia. Fig. 70. Basidiospores. Figs. 7 1-73. Dentocorticium sulphurellum (from Cain 3357). Fig. 71. Dendrohyphidia. Fig. 72. Basidia. Fig. 73. Basidiospores. Figs. 74-76. Dentocorticium ussuricum (from type). Fig. 74. Dendro­ hyphidia. Fig. 75. Basidia. Fig. 76. Basidiospores. Figs. 77-79. Laeticorticium pilatii (from type). Fig. 77. Subicular hyphae. Fig. 75. Compactly arranged, vertically oriented hyphal elements. Fig. 79. Dendrohyphidia. Laeticorticium and related genera 119 clamped, frequently aggregated into hyphal white. Microscopically, the large allantoid strands; dendrohyphidia (Fig. 67) abundant spores and branched hyphidia are distinc­ and forming a distinct catahymenium, 3-7 tive. The spore print (JLL 11855) is white. µm diam, variously branched and lobed, Specimens examined clamped, septa without clamps towards the extremities, olive brown, sometimes associated CANADA, ONTARIO. Toronto, on Salix with thick-walled vesicular structures (Fig. sp., Cain (TRTC 3387, BPI); Toronto, on 68) from which they originate; basidia (Fig. Salix sp., Jackson & Cain (TRTC 6373, BPI). 69) 30-40 (-45) × 4-6 µm, becoming tortuous, QUEBEC. Blue Sea Lake, on hardwood, long-clavate, 4-sterigmate, sterigmata up to Macrae (DAOM 53115); Iberville, on hard­ 4 µm long; basidiospores (Fig. 70) 6-10 × wood, Br. Marie-Anselme 172 (DAOM 22960 2.5-4 µm, cylindrical, cylindrical-ellipsoid, to SYRF). U.S.A. MINNESOTA, Itasca State ellipsoid, hyaline. Park, on hardwood, Lombard, French & Gil­ This species, known only from the type, is bertson (CFMR, FP 100778). NEW YORK. so morphologically distinct that it warrants Griffins, on Acer spiculum Lam., Peck, IV recognition. Dentocorticium brasiliense is 1878, TYPE (NY); Tully, on Tilia ameri­ readily diagnosed by a heavily fissured hy­ cana L., Lowe 11855 (SYRF); Phoenix, on menial surface, color of fertile areas, brown Acer sp., Pennington, 20 X 1917 (SYRF); subicular hyphae, and size and shape of Cazenovia, on Acer sp., Czabator 2225 spores. It is associated with a white rot. (SYRF); Clark Reservation, Jamesville, on hardwood, Lowe 14474 (SYRF); on hard­ Dentocorticium sulphurellum (Pk.) Larsen & wood, Roskin 52 (CFMR). NORTH CARO­ Gilbertson, Norw. J. Bot. 21:226. 1974. Hyd­ LINA. Bernardsville, on hardwood, Lowe num sulphurellum Pk., N.Y. State Mus. Rept. 4434 (SYRF); Pisgah National Forest, on 31:38. 1879. Grandinia sulphurellum (Pk.) Liriodendron tulipifera L., Lowe & Gilbert- Burt in House, N.Y. State Mus. Bull. 266:44. son (Lowe 11174) (SYRF). 1925. Laeticorticium sulphurellum (Pk.) Gil­ Dentocorticium ussuricum (Parm.) Larsen & bertson, Mycologia 54:673. 1962. Gilbertson, Norw. J. Bot. 21:226. 1974. Laeti­ Basidiocarps apparently annual, up to 0.5 corticium ussuricum Parm., Acad. Sci. Esto­ mm thick, not easily separable, yellow to al­ nian SSR, Biol. Ser. 14(2):229. 1965. most white when dry; hymenial surface almost Basidiocarp annual, effused up to 3 cm, up smooth or with hemispherical, wart-like pa­ to 400 µm thick, adherent, firm; hymenial pilli; subiculum thin, soft, tending to crack surface dark ochraceous brown (near 5.0 YR on drying; sterile margin finely fimbriate to 4/2) with scattered bluntly conical warts up tomentose, abrupt, not thinning out. to 100 µm long, the apices entire, white con­ Hyphal system dimitic; subicular hyphae colorous; subiculum white, firm-fibrous, up 3-4 µm diam, compactly interwoven, of two to 300 µm thick; sterile margin narrow, white, kinds; some generative, thin to moderately fibrillose, curling away in places. thick-walled, sometimes branched, occasion­ Hyphal system monomitic; subicular hyphae ally with clamp connections; some skeletal 2-4 µm diam, septate, clamped, moderately (? fiber hyphae) thick-walled, aseptate, pro­ thick-walled; dendrohyphidia (Fig. 74) abun­ fusely branched, 1-1.5 µm diam; dendro­ dant, intricately branched at the apex, origi­ hyphidia (Fig. 71) abundant in the hymenial nating in candelabrums with the basidia; layer, 1-2 µm diam, often imbedded; basidia basidia (Fig. 75) 30 × 3-4.5 µm, clavate, (Fig. 72) 30-40 × 4-6 µm, clavate, 4-sterig­ 4-sterigmate, sterigmata up to 4 µm long; mate, sterigmata up to 5 µm long; basidio­ basidiospores (Fig. 76) 5-6 × 2.5 µm, cy­ spores (Fig. 73) 7-9.5 × 2.5-4 µm, allantoid. lindric, slightly curved. This species is probably widely distributed This species, reported only from Estonia, throughout central and northeastern United resembles the North American species L. States and adjacent areas of Canada, and sulphurellum in having a warted or grandi­ southward in the Appalachian Mountains to nioid hymenial surface and cylindric spores. North Carolina. Fresh specimens in the field It differs distinctly from that species in its are bright sulfur yellow but the color fades smaller spores and darker colored basidio­ in dried specimens, which are often almost carp. 120 M. J. Larsen & R. L. Gilbertson

Specimens examined buricae, Parmasto TAA 14451 (paratype, ESTONIA RPSS. Regio Primorsk, reservatum exsiccati 65 in Corticiaceae URSS I); regio Kedrovaia Padj., ad ramum emortuum Ligu­ Primorsk, distr. Lazovski, insula Petrovna, ad strinae amurensis in silva mixta, Parmasto ramum arboris frondosae deiectuni in taxeto, TAA 13, 836, in Corticiaceae URSS 73, ‘para­ Parmasto TAA 15927 (paratype, exsiccati 64 typus’ (BPI). in Corticiaceae URSS I).

SPECIES INCERTAE SEDIS ACKNOWLEDGEMENTS Laeticorticium pilatii Parm., Acad. Sci. Esto­ nian SSR, Biol. Ser. 14(2):228. 1065. The use of herbarium facilities or the loan Basidiocarps annual. effused up to 10 × 5 of specimens by the curators of BPI, FH, cm, up to 800 µm thick, firm, somewhat fragile PAC, NY. DAOM. and TRTC are gratefully in spots. adherent. becoming deeply fissured acknowledged. This research, including col­ and then exposing the subiculum; hymenia1 lecting in 1962 and 1963, was supported in surface somewhat viridescent (near 10.0 YR part by National Science Foundation grant G24382 to Gilbertson, and by McIntire- 6/8 or 10.0 YR 5/6: to 5/8), nearly smooth to faintly merulioid, often waxy at the apices Stennis project no. 2016-4166-23in the Uni­ of folds; subiculum concolorous with the hy­ versity of Arizona Agricultural Experiment menial surface to pale brown; margin narrow, Station. thin; basidiocarps dull violet-red in KOH. Subicular hyphae (Fig. 77) (1-) 2-4 µm diam, septate, clamps lacking, hyaline to pale REFERENCES yellow, branching extensively and becoming narrower with successive branching; cata­ hymenium composed of compactly arranged vertically oriented hyphal elements (Fig. 78) that are up to 6.5 µm diam, moderately thick- walled, yellow, septate, clamps lacking, often constricted at the septa and then the indi­ vidual hyphal cells swollen, usually branch­ ing directly below the septa; dendrohyphidia (Fig. 79) intricately branched, apparently aseptate and dissolving to some extent in KOH, incrusting reddish brown granular ma­ terial also dissolving in KOH; basidiospores, probasidia, and mature basidia not observed (‘sporae oblongo-ovatae, uno latere depressae, non amyloidea, (7.5)-8-10 × 4-4.5 µm’ - Parmasto). As pointed out by Larsen & Gilbertson (1974), the taxonomic position of this species is uncertain because of a lack of precise data on basidial ontogeny in the type collections. Parmasto (1965) described the probasidia for this species as ‘obovoidea, deinde subfusoidea, clavata, non optime visibilia.’ When his illu­ stration (p. 227, Fig. 13) is taken into ac­ count, one may conclude that the species is closely related to Dendrocorticium.

Specimens examined ESTONIA RPSS. Regio Primorsk, reservatum Kedrovaia Padj., ad ramum Fraxini mans­ Laeticorticium and related genera 121

9 - Botany