Fungal Diversity New species and records of Crepidotus from Costa Rica and Mexico Bandala, V.M.1*, Montoya, L.1 and Mata, M.2 1Dept. Biodiversidad y Sistemática, Instituto de Ecología, A.C., P.O. Box 63, Xalapa, Veracruz 91000, Mexico 2Instituto Nacional de Biodiversidad, P.O. Box 22-3100, Santo Domingo de Heredia, Costa Rica Bandala, V.M., Montoya, L. and Mata, M. (2008). New species and records of Crepidotus from Costa Rica and Mexico. Fungal Diversity 32: 9-29. The new species C. pseudoantillarum and C. herrerae are described from Costa Rica and Mexico respectively. Records of C. pseudoantillarum from different localities in Mexico are presented, as well as the first report of C. albescens from Costa Rica. The newly described species, related to the taxa with smooth spores, gelatinous tissues and clamped hyphae, prompted us to make a reexamination of type specimens of C. albescens, C. antillarum, C. betulae, C. cinchonensis and C. phaseoliformis. On account of the morphological features are recognized: C. albescens (= C. betulae, C. phaseoliformis) and C. cinchonensis. The type of Tremellopsis antillarum is found to be a member of Crepidotus uber but under the name of C. antillarum s. auct. a distinct taxon has been obscured, which is being described here as C. pseudoantillarum. Descriptions, illustrations of microscopic features and discussions are provided. Key words: Crepidotaceae, taxonomy, tropical fungi, wood-inhabiting fungi Article Information Received 6 June 2007 Accepted 19 January 2008 Published online 30 September 2008 *Corresponding author: V.M. Bandala; e-mail: [email protected] Introduction occurrence (in some cases embracing far-off points) is reasonably well supported (Horak, There has been an increment in studying 1964; Singer, 1973; Bigelow, 1980; Luther and the macrofungi of Central and South America Redhead, 1981; Redhead, 1984; Nordstein, (Capelari et al., 2006; Lechner et al., 2006; 1990; Pereira, 1990; Senn-Irlet, 1995a; Astier, Ovrebo and Baroni, 2007; Ortiz-Santara et al., 1998; Senn-Irlet and De Meijer, 1998; Bandala 2007). In this paper we report new records and et al., 1999, 2006, 2008; Bandala and Montoya, new species of Crepidotus from Mexico and 2000a,b, 2004; Krisai-Greilhuber et al., 2002; Coast Rica. Crepidotus includes several species Ripková et al., 2005). While few species are of lamellate, often sessile, small, brown-spored recognized to have a rather widespread distribu- mushrooms that constitute an important tion [e.g. C. applanatus (Pers.) P. Kumm, C. component in the community of forest sapro- epibryus (Fr.) Quél. or C. cinnabarinus Peck] trophic fungi. They occur in a wide variety of (Pilát, 1948; Hesler and Smith, 1965; Luther ecosystems normally colonizing small plant and Redhead, 1981; Senn-Irlet, 1995a; Bandala debris and fallen wood. Such habits could be et al., 1999), most representatives (including the reason for the worldwide distribution of the several taxa currently known only by their genus and perhaps the patterns of occurrence respective diagnoses) display an apparently currently recorded for the species, in part being restricted or fragmentary distribution. Several influenced by the local ecological conditions, species described from both hemispheres, have rather depend on selected sampling areas (or been recorded in a variety of types of intensity of explorations). A small group of vegetation in Mexico (Bandala et al., 1999; American species have been well documented Bandala and Montoya, 2000a,b, 2004; Krisai- (Hesler and Smith, 1965; Singer, 1973) with Greilhuber et al., 2002). Type studies of additional information on variation of taxono- phenotypically similar Crepidotus species mically important morphocharacters, and their describeed from Mexico (Bandala et al., 1999, taxonomic circumscription and geographic 2006; Bandala and Montoya, 2000a,b, 2004), 9 revealed that there are eight Mexican species already noted also by Hesler and Smith (1965), that currently show an apparent endemism Horak (1968) and Singer (1947), is in poor (Singer, 1957, 1973), excluding C. rubrovinosus condition of preservation that prevents making Bandala, Montoya & E. Horak (2006), recently an appropriate study. Data introduced by this found also in Central America and not treated latter author suggest that the microscopic here. In Costa Rica, a single sample of C. information provided in his monograph is a calolepis subsp. polycistis Singer, was gathered composite description resulted by including his during 1925-1926 by P.C. Standley and J. collections from Florida, as well as the type Valerio in El Cerro de Las Vueltas (San José) specimen of Crepidotus cinchonensis Murrill (Singer, 1973). (1913) from Jamaica. Following Singer (1947), During ongoing revisions of Crepidotus the so-called C. “antillarum” was therefore a (Bandala et al. 2008; Bandala and Montoya, taxon microscopically characterized by smooth, 2008), we studied some collections from ellipsoid (“…with the inner side flatter…”) Mexico and Costa Rica that represent new basidiospores, clamped hyphae, gelatinous species and new records related to the group of hyphae in the pileus trama and clavate or at smooth-spored taxa with gelatinized, clamped times subcapitate cheilocystidia (Hesler and hyphae that cluster around C. albescens (Murrill) Redhead. Besides the opportunity to Smith, 1965; Horak, 1968; Singer, 1973; Pegler, give information about their ranges of extension, 1983; Senn-Irlet and De Meijer, 1998). Our the comparative study of the samples with the reexamination of Tremellopsis antillarum type reexamination of type specimens revealed collection Duss s.n. revealed, however, informa- interesting information to support the new tion that agrees in part with the aforementioned species and to provide additional data for the authors, especially with observations by Horak taxonomic status of some type collections. (1968) regarding the basidiospore features (see below). Our results after studying the type of T. Materials and methods antillarum and collections from Costa Rica and Mexico, compared with published descriptions Macrocharacters were observed on fresh of all phenotypically related taxa, led to basidiomes collected in Mexico and Costa conclude that: i) the specimen of Duss s.n. falls Rica. Specimens from Santuario del Bosque de within the range of variation recorded for C. Niebla (a cloud forest adjacent to the Instituto uber (Berk. & M.A. Curt.) Sacc. and perhaps it de Ecología A.C. at Xalapa) were collected in represents a sample of this species, and ii) we monitored sites (cf. Bandala et al., 2006). recognized two undescribed species (one of Colour codes in descriptions refer either to them obscured under the name C.” antillarum” Kornerup and Wanscher (1967, e.g. 2A2–3) or s. auct.) which share taxonomically important to Munsell (1994, e.g. 2.5Y 8/2–3). Methods and unique set of striking features with the employed in the microscopic analysis of group of taxa around C. albescens, i.e. specimens, including basidiospore measure- ments and their statistics, SEM and symbols, ellipsoid-reniform basidiospores, clamped are the same as those used by Bandala et al. hyphae, and gelatinized tissues. Additionally, (1999, 2006) and Bandala and Montoya (2000a, on the basis of microscopic characters shown 2004). Photographs of microscopic features by the collection of Duss s.n. (clampless were taken from hand sections of revived hyphae, relatively small spores) and the type tissues mounted in 3% KOH or Congo Red 1% specimen of Crepidotus cinchonensis (clamped aqueous solution and observed on a microscope hyphae, broad spores), they could hardly be equipped with a digital camera. Herbarium considered to belong to the same taxon. Type acronyms are according to Holmgren et al. studies, descriptions and discussions on these (1990). taxa are presented below in three sections, one includes the reevaluation of Tremellopsis Results antillarum, other the description of the two The Tremellopsis antillarum Pat. type new species, and the third, the study of specimen, Duss s.n. from Guadaloupe, as collections related to C. albescens. 10 Fungal Diversity Taxonomy basidiospores and some of the features of A. Reevaluation of Tremellopsis antillarum certain tissues can be recovered. Singer (1947) recognized the taxon as Crepidotus especially Tremellopsis antillarum Pat., in Duss, Enum. pointing out the macromorphology in combi- Champ. Guad. p.13 (1903). nation with basidiospore features seen in the (Figs 1a, 2-3a-b) holotype. The basidiospores in fact were the = Crepidotus antillarum (Pat.) Singer, only microscopic structure clearly indicated by Lilloa 13: 62 (1947) Singer to have been observed in the holotype Material examined: GUADALOUPE. Matouba, [with regard to basidia in 1973: 429, he wrote: no date, Duss s.n. (Holotype, FH, Patouilliard “…The type of C. antillarum is said to be 2-4 Herbarium No. 224) Tremellopsis Pat. (in Duss op. cit.) was spored (which I could not verify any more)…”]. conceived as a “gélatineux-tremelloïde” genus His previous information (Singer 1947) “… with “…basides claviformes, non septées, derived from the type specimen in the portant 2-4 stérigmates… cystides nulles… Patouilliard herbarium … secured by studying spores ocracées”. Macroscopic data in the the type of C. cinchonensis and some fresh protologue for the single species recognized by material collected by myself in South N.T. Patouilliard (T. antillarum) are the Florida…”, denotes that the author provided a following: “…plante de 1-2 centim. de haut composite description. He concluded that sur 2-3 de large… réceptacle formant une “…summing up the data obtained from these three masse gélatineuse, composée de feuillets sources, one will attribute to C. antillarum… dressés, chiffonnés, entiers ou lobés, plus ou spores (8-)8.2-10.5(-11) × 5.2-6.8 µm, smooth… moins rameux, rayonnants autour d´un point ellipsoid, with the inner side flatter… basidia central, sessile ou élevé sur une portion (16-)20-37 × (5-)7.5-10.3 µm, either 2-spored or stiptiforme trés courte. Feuillets grisâtres, 4-spored (the Florida collection… was entirely devenant roux-ocracés, peu épais…”. bisporous; the other collections are predominantly Microscopic features seen in the holotype are: tetrasporous)…; cheilocystidia ventricose… the basidiospores 6.5-9(-9.5) × (4-)4.5-6 µm, x = upper ventricosity often appearing as if the 7.7 × 5.1 µm, Q = 1.50, ellipsoid, often weakly cheilocystidia were capitate… 33-51 × 5.5-10.3 attenuated towards apex, then more or less µm…, hyaline hyphae with clamp connections… amygdaliform on side view, smooth, thick- trama of the pileus rather thin, subgelatinous…”. walled (≤ 0.5µm wide), pale yellowish-brown, A similar concept was maintained until his work under SEM smooth and lacking germ pore of 1973. One of his collections from Mexico (Figs 1a and 3a-b). Tissues hardly revived with (Singer M 8093) studied here fits indeed that KOH but both pileus and hymenophoral concept. Hesler and Smith (1965) followed Singer tramae consist of slightly gelatinized, hyaline, providing a composite description also with C. clampless hyphae (at least most septa recover- cinchonensis as a synonym. These authors as ed). Basidia, cheilocystidia and pileipellis not well as Horak (1968), stressed the bad state of recovered (in protologue the basidia were the holotype of Tremellopsis antillarum, Horak reported 30-35 × 10 µm). in fact, underlined not having found cheilo- Notes: Judging by its present, rather cystidia, hence referring to information by papyraceous consistency and appearing strongly Singer (1947) and Hesler and Smith (1965) for pressed, probably the material of Duss s.n. was the interpretation of the character. We share wet or overmature when collected, and consi- Horak’s (1968) opinion that in the material of dering its gelatinous nature, it practically collapsed Duss s.n. it was not possible to verify the after drying. Data provided by Duss (1903), presence of cheilocystidia (although the proto- indeed, rather suggest the inappropriate condition logue indicates indeed the absence of cystidia). of his collection when gathered, perhaps the The pattern of size and shape of the basidio- reason why N.T. Patouilliard related it to spores observed in this revision also agrees with tremelloid forms. The protologue does not the results of Horak (op. cit.) who showed that mention the presence or absence of clamps but it the specimen of Duss s.n. is characterized by its specifies the lack of cystidia. Lamellae edges moderately small-sized (7.5-9 × 5-6 µm), can hardly be analyzed and no more than the ellipsoid to amygdaliform basidiospores. Our 11 Fig. 1. a. Tremellopsis antillarum. Basidiospores (from holotype). b. Crepidotus cinchonensis (from holotype). Bars = 10 µm. antillarum as described above. We interpret that the collections that Singer (1947) treated under C. “antillarum” are not the same as Tremellopsis antillarum, since the set of characters that include medium to large-sized, ellipsoid to oblong and more or less kidney-like or bean-like shaped (due to a flattening or a weak curving inward in the adaxial face) basidiospores, cheilocystidia mostly clavate, pileipellis bearing somewhat undifferentiated terminal elements, and tissues with gelatinized, clamped hyphae (Figs 4-6f-g) are features that taxonomically Fig. 2. Scatter plot of basidiospore size (means) in show similarity to the group of species near C. collections of Tremellopsis antillarum (×, holotype), albescens rather than to Tremellopsis antillarum Crepidotus albescens (□), C. cinchonensis (+, holotype), or even Crepidotus cinchonensis. We found that C. herrerae ((cid:85)), and C. pseudoantillarum ((cid:123)). C. cinchonensis and Tremellopsis antillarum are type study did not reveal clearly the presence of only superficially similar based on macroscopic clamps at least in many accurately recovered features. Hand sections of the holotype of C. septa. cinchonensis (JAMAICA. Cinchona, wet moun- On account of the ellipsoid to amygda- tainous region, 25 December 1908-8 January liform, moderately small-sized basidiospores, 1909, W.A. Murrill & E.L. Murrill 610, NY) gelatinized, clampless hyphae, in combination revived with difficulty in KOH preventing us with the relatively small, grayish basidiome, the from developing an appropriate evaluation of specimen of Duss s.n. that supports Tremellop- gelatinized layers in pileus and lamellae tramae sis antillarum, in our opinion, represents a (cf. e.g. key in Hesler and Smith 1965). How- member of C. uber (for description cf. Singer, ever, it presents gelatinized, clamped hyphae 1973; Senn-Irlet and De Meijer, 1998). The that more or less recall puzzle-like elements, taxonomic implication of all this is the existence, therefore it differs from Tremellopsis antillarum in fact, of a distinct taxon represented by but resembles members close to C. albescens specimens inhabiting fallen wood in tropical or (like C. “antillarum” s. auct.). Crepidotus cincho- subtropical forest from Mexico, the Caribbean nensis is also distinguished by its pileipellis, and Central and South America. This taxon apparently a cutis, composed of undifferentiated exhibits just the set of characters fixed until now terminal elements, basidia 23-35 × 7-11 µm, for what has been called C. “antillarum” after clavate, 4-spored, clamped, and basidiospores Singer (1947) (Hesler and Smith, 1965; Horak, (7.5-)8-10 × 5-6.5 µm (x = 8.9 × 5.8 µm, Q = 1968; Singer, 1973; Pegler, 1983; Senn-Irlet and 1.54), ellipsoid, mostly without an adaxial De Meijer, 1998) but it excludes Tremellopsis concavity (so appearing not reniform)(Figs 1b-3 12 Fungal Diversity Fig. 3. Scanning electron micrographs of Crepidotus basidiospores. a-b. Tremellopsis antillarum (from holotype). c-d. Crepidotus cinchonensis (from holotype). Bar: 1 µm, except b = 2 µm. c-d). L.R. Hesler wrote in a note of revision and therefore Tremellopsis antillarum is accompanying the holotype (indeed the same interpreted as a later synonym: data later published by Hesler and Smith, 1965) Crepidotus uber (Berk. & M.A. Curt.) Sacc., that most cheilocystidia are collapsed against Syll. Fung. 5: 878 (1887). the gill edges. In fact, the cheilocystidia revived Basionym: Agaricus uber Berk. & M.A. Curt., with difficulty and prevent us to describe with Proc. Amer. Acad. Arts Sc. 4: 117 (1858). Synonym: Tremellopsis antillarum Pat., in Duss, confidence the shape of individual cells, to have Enum. Champ. Guad. p.13 (1903). an appropriate interpretation of their pattern of = Crepidotus antillarum (Pat.) Singer, Lilloa 13: variation and compare them within the range of 62 (1947). variation of this character shown by collections Crepidotus uber is a small, white, gelatinous of C. “antillarum” s. auct. fungus inhabiting the tropical and subtropical In conclusion, C. cinchonensis does not forest from the Gulf of Mexico area, Caribbean seem to share unique morphological characters and South America (Singer, 1973; Pegler, 1983; with the so-called C. “antillarum” or at least the Senn-Irlet and De Meijer, 1998; Bandala and available data from the holotype do not allow us Montoya, 2002). to accurately place it within that taxon. For the On account of the aforementioned infor- time being C. cinchonensis should be kept mation, as well as the data obtained from separate since it is also fairly different from different examined specimens (from Costa Rica Tremellopsis antillarum or even shows a certain and Mexico, type specimens supporting species resemblance to C. virgineus Har. Takah. related to the group of C. albescens), all (Takahashi, 2003). The holotype of Tremellopsis compared with published descriptions of C. antillarum strongly resembles members of “antillarum” s. auct., it is now accepted that Crepidotus uber in having similar basidiospores three distinct species can be recognized, two of (size, shape) and gelatinized, clampless hyphae, them representing undescribed taxa. These three 13 species share a consistent set of characters, i.e. rounded flabelliform or somewhat petaloid, with clamps, gelatinized tissues, ellipsoid, more or or without a slot in the rear portion (when seen less reniform and smooth basidiospores, and from the hymenophore), this produces two constitute a group of taxa phenotypically similar short, lobe-like hemispheres, then somewhat to the species of the C. mollis (Schaeff.) Staude rounded reniform, whitish, whitish-translucent group which form gelatinized tissues, have to pale grayish, brownish in parts by spores smooth basidiospores but lack clamps. Crepidotus deposit on surface, not or slightly translucent albescens described from the USA (Murrill, striate, variably viscid (sticky to the touch), hy- 1916 as Geopetalum; Redhead, 1984) is distin- grophanous, tomentose to tomentose-fibrillose, guished by the subcylindric to more or less almost minutely villose near point of attach- narrowly lageniform, remarkably elongate ment; margin incurved, later inflexed to cheilocystidia in combination with a pileipellis moderately straight, thin, weakly tomentose- made of more or less filamentous, undifferen- fimbriate to glabrous, wavy (mainly when fully tiated terminal elements (Figs 6a-e and 9-11). expanded), slightly exceeding the lamellae. The two new species differ in having somewhat Lamellae whitish becoming pale brown, some large basidiospores and clavate or moderately with pinkish shades, with whitish, fimbriate, capitate cheilocystidia (Figs 2, 4-6f-i and 7-8). somewhat irregular edges which are somewhat One of these species, which corresponds to what elastic; adnexed to narrowly adnate, some has been called C. “antillarum” s. auct., is weakly subdecurrent, concurrent to a lateral distinct in that it combines a pileipellis with point, subdistant, broad (≤ 4 mm broad), more undifferentiated terminal elements, while the or less ventricose, lamellulae 3-4 different other undescribed taxon combines a pileipellis length. Stipe in young stages lateral, rudimen- bearing distinctly versiform (i.e. constrictions, tary (< 2 mm long.), whitish, pruinose, with age short outgrowths, contorted), ventricose ter- absent or persisting as a lateral, glabrous knob minal elements similar to its cheilocystidia. The (when seen from the hymenophore) but the three species are described below. pileus is directly attached laterally or almost dorsally to the substratum; basal mycelium B. Description of new species white, present or absent. Context watery, whitish, thin to more or less thick from center Crepidotus pseudoantillarum Bandala, Montoya backwards (2-5 mm thick), hygrophanous then & M. Mata, sp. nov. (Figs 2, 4-6f-g & 12a) opaque, soft, elastic, unchanging on exposure. MycoBank: 512445 Odor and taste not distinctive. Etymology: referring to a false Tremellopsis anti- Basidiospores (7-)7.5-11 × (4-)4.5-5.5(- llarum. 6.5) µm, x = 8.2–9.9 × 4.8-5.7 µm, Q = 1.7- Pileus 4-42 mm latus, dimidiatus vel flabellatus, 1.79, oblong to ellipsoid or moderately narrowly convexus, albidus, tomentosus vel tomentoso-fibrillosus, striatulatus, hygrophanous, viscidus. Lamellae subdistantes, ellipsoid, weakly applanate or depressed adax- albidae, dein brunneae, marginem fimbriatae. Stipes ially then slightly reniform, apiculus very small, primo lateralis, minutus, senectute saepe deest. Contextus apex weakly tapered but rounded, wall at times albidus, immutabilis, gelatinosus. Basidiosporae (7-)7.5- bearing a discontinuity resembling a germ pore, 11 × (4-)4.5-5.5(-6.5) µm, ellipsoideae vel subreniformeae, smooth, thin- to slightly thick-walled (≤ 0.5 µm laevis, ochraceae. Basidia 20-35 × 5-7 µm, clavata, bispora vel monospora. Cheilocystidia 27-65 × 4-7(-8) × thick), yellow to pale yellowish-brown; under (apicem) 6-13(-14) µm, clavata vel clavato-capitata, SEM smooth and lacking germ pore. Basidia hyalinis, gelatinous. Pileipellis ex hyphis hyalinis, cylin- 20-35 × 5-7 µm, 2-spored, often monosporic, draceis, laxe intricatis, subtrichodermium vel cutem clavate, thin-walled, hyaline, clamped. Pleuro- formantibus. Tramate pilei et tramate hymenophoralis cystidia absent. Cheilocystidia 27-65 × 4-7 (-8) gelatinosae. Fibulae praesentes. COSTA RICA. Guana- caste: Arenal, Volcán Tenorio, Hacienda Montezuma, 5 µm, numerous, narrowly clavate to subclavate, May 2000, López 1296 (Holotypus, INB; Isotypus often narrowly utriform, apex rounded or sub- XAL). capitate 6-13 (-14) µm wide, occasionally sub- Pileus 4-42 mm broad, in young stages cylindric-capitate, straight or somewhat sinuous, ungulate to more or less campanulate, becoming hyaline, thin-walled, clamped, gelatinized, pro- convex or almost plano-convex, subcircular or ducing a more or less dense, refringent layer on circular to dimidiate, at times more or less lamellae edge.Pileipellis a loose trichoderm or a 14 Fungal Diversity Fig. 4. Crepidotus pseudoantillarum (from holotype). a. Basidiospores. b. Pileus trama hyphae. c. Cheilocystidia. d. Basidia e. Pileipellis. Bars: a, c & d = 10 µm, b & e = 20 µm. 15 Fig. 5. Crepidotus pseudoantillarum (from holotype). a. Tangential section of pileipellis. b. Cheilocystidia. Bars: a = 20 µm, b = 10 µm. transition to a loose cutis, composed of cylin- or wood, in tropical and subtropical cloud forest, dric, interwoven hyphae 5-8(-11) µm wide, at 800-1700 m alt. hyaline, simple or bifurcate, clamped, thin- or Known distribution: Bermuda, Brazil, slightly thick-walled (≤ 0.5 µm thick), smooth, Colombia, Costa Rica, Cuba, Jamaica, Martini- with a variable number of undifferentiated que, Mexico. (rarely very narrowly sublageniform or elongate Material examined: COSTA RICA: Guanacaste: -subcapitate), straight terminal elements, the Arenal, P.N. Volcán Tenorio, Hacienda Montezuma, 5 May 2000, López 1296 (Holotype, INB; Isotype XAL). layer is ungelatinized and variable in depth and MEXICO. Chiapas: Mpio. Ocozocuautla, Reserva in density of hyphae, at times in some areas Laguna Bélgica, 5 September 2006, Bandala 4211 (XAL). even of a single specimen the ascendant hyphae Veracruz: 7 km S of Montepio, Estación Biológica de are more tightly packed and projecting or in Los Tuxtlas, 20 May 1969, Singer M 8093 (F, as other areas these hyphae are more postrated. Crepidotus antillarum). Mpio. Rafael Lucio, Sta. Pileus trama (in tangential section) differen- Bárbara Farm, 18 February 1986, Bandala 735; Mpio. tiated in two layers, one beneath pileipellis, Apazapan, Apazapan, 7 August 1994, Leal 458 (XAL). Other material examined: CUBA. Prov. Pinar del gelatinized, refringent, variable in depth, Río, Candelaria Co., Reserva Sierra del Rosario, 9 composed of more or less filamentous hyphae 2- December 1994, Bandala 2720 (XAL). JAMAICA. 5 µm wide, hyaline, thin-walled, smooth, some Marce's Gap, mountainous region, 29 December 1908-2 occasionally obscurely punctate, somewhat flex- January 1909, Murrill & Murrill 686 (NY, as Crepidotus uous, more or less radially oriented and loosely cinchonensis). interwoven; below that layer is a distinctive Notes: Distinctive features that separate moderately compact, gelatinized but not refrin- C. pseudoantillarum from other white, gent stratum comprising most of the pileus gelatinized, clamped, smooth-spored species context and composed of colorless, thin-walled, are the clavate to more or less subcapitate subcylindric to subventricose, simple, bifurcate cheilocystidia and a pileipellis composed of or occasionally ramified hyphae (3-)4-15(-17) undifferentiated terminal elements. This taxon µm wide, often short-bifurcate, somewhat encompasses the attributes of what Singer irregularly arranged forming a puzzle-like (1947) understood and circumscribed as C. structure. Hymenophoral trama with a medio- “antillarum”, a concept later extended in stratum, irregular to subregular, composed of subsequent literature (for further information hyphae similar to those from lower part of please refer to the discussion under Tremel- pileus trama; laterostrata refringent, gelatinized, lopsis antillarum above). Crepidotus pseudo- composed of filamentous, colorless to pale antillarum seems to enclose some variants yellowish, thin-walled hyphae 2-5 µm wide, producing different numbers of spores per loosely and more or less divergently arranged. basidium. Collections examined here often Clamp connections present in all tissues. presented 2-spored or monosporic basidia; the Habitat: Gregarious, on decaying branches taxon is reported to include specimens (1-)2(3-)- 16 Fungal Diversity Fig. 6. Scanning electron micrographs of Crepidotus basidiospores. a-e. C. albescens (a-b: from holotype; c: Kelly 158, holotype of C. phaseoliformis; d-e: Earle 241, holotype of C. betulae). f-g. C. pseudoantillarum (from holotype). h-i. C. herrerae (from holotype). Bars: a-e = 1 µm, f-i = 2 µm. spored, 2-4-spored or 4-spored basidia (Singer, laterostrata, being more refractive in some than 1947, 1973; Pegler, 1983; Senn-Irlet and De in others. Singer (1973) observed something Meijer, 1998; all as C. antillarum). The similar among his specimens. Pegler (1983) gelatinous layer resting just beneath the reported the subhymenial layer as being poorly pileipellis can be thick and refringent in fresh developed and the hymenophoral trama or well revived specimens, although in some subgelatinized, not mentioning the pileus trama cases it is weakly refringent but differentiated characteristics. Senn-Irlet and De Meijer (as in specimen Bandala 4211) or it can be (1998) described a distinct gelatinous layer very compact and hence apparently absent behind the subhymenium and jigsaw-like cells (Bandala 735, 2720), in both later situations of the pileus trama. Our study of specimens of the pileipellis hyphae rather rest on the pileus C. pseudoantillarum and other related members trama. At times some lamellae (even of a same revealed that a well preserved sample from specimen) in tangential section show a which a good revived tangential section can be variation in the depth of the gelatinized obtained, allows to observe the disposition of 17 the gelatinized layers, one of them located just that macroscopy has been used as the first beneath the pileipellis, another just below the criterion of segregation between a more consis- lower part of the context (i.e. the continuation tently stipitate taxon (Simocybe) and another of the subhymenium), and finally, the apparently sessile (Crepidotus). Through C. laterostrata in the lamellae (cf. Fig. 11a-b) (at pseudoantillarum and allied species as well as times producing a dense, gelatinized lamellae other lineages, Crepidotus not only shares with tip where the cheilocystidia are immersed). Simocybe morphologically similar spores Such layers, even in the same sample, vary to a (yellowish to yellowish-brown or brownish, greater or lesser degree both in depth and smooth, variably reniform, lacking germ pore) refraction, and consequently one or more layers (Pegler and Young, 1975; Senn-Irlet, 1995b) can be better defined. A similar variation, more but also anatomical details of the pileipellis dependent on the influence of weather conditions (more than with Agrocybe and other Bolbitia- and later drying of the material, is, in fact, ceae which differ in having a cuticle in a observed also among samples representing palisadoderm, Watling, 1965; Watling and different species of Crepidotus that form Largent, 1976). The core species of Simocybe, gelatinized tissues (Singer, 1973; Nordstein, that includes European species like S. centun- 1990; Senn-Irlet, 1995a; Bandala and Montoya, culus (Fr.) P. Karst. and S. sumptuosa (P.D. 2004; Gonou-Zagou and Delivorias, 2005). Orton) Singer, or American members like S. Apart from the diagnostic set of characters alachuana (Murrill) Singer or S. atomacea of C. pseudoantillarum the size of the basidio- (Murrill) Singer among others, certainly have a spores can be indicative also of taxonomic pileipellis with a closer arrangement pattern, differences. Fig. 2 depicts the mean values of bearing more defined cystidia-like terminal length and width of the basidiospores based on elements and hence appearing more tricho- available collections of the three species dermoid. However, other members like S. studied in this group. Comparing these values, iberica G. Moreno & Esteve-Rav. and S. the specimens of C. pseudoantillarum show a quebecensis Redhead & Cauchon possess a different range in relation to that observed on pileipellis with a looser or somewhat entangled C. albescens and the next new species treated arrangement, composed of interwoven, more or (see below). This later taxon presented larger less filamentous elements, rather radially basidiospores, with a range above that displayed oriented, hence appearing in parts as a loose by C. pseudoantillarum which at the same cutis or a loose trichodermoid pileipellis time, showed a larger basidiospore range than (Redhead and Cauchon, 1989; Moreno and C. albescens. Collections of C. albescens Esteve-Raventós, 1990; Senn-Irlet, 1995b; perhaps produce small-sized basidiospores due pers. obs.). The pileipellis in both cases seems to the consistent presence of tetrasporic basidia, to be comparable (if not identical) with that in comparison with the other two species which found in several Crepidotus species, e.g. C. possess bisporic or monosporic basidia. Further eucalyptinus Maire & Malençon, C. lepton confirmation of the taxonomic value of the (Berk.) Sacc., C. pezizula (Berk. & Broome) basidiospore size will be achieved when the Sacc., C. variabilis (Pers.) P. Kumm., among number of collections be increased to corrobo- others (Malençon and Bertault, 1975; Pegler, rate if those patterns are effectively consistent. 1986; Senn-Irlet, 1995a; pers. obs.). In cases It is interesting to comment additionally such as Simocybe fulvifibrillosa (Murrill) that a similar situation in the size of the Singer, S. ovalis Singer or S. coroicensis Singer basidiospores is well known among bisporic (Singer, 1973) a pileipellis like that of many and tetrasporic forms of Simocybe (Senn-Irlet, Crepidotus, i.e. with more prostrate, relatively 1995b), the sister genus of Crepidotus (Moser, compact hyphae and with scattered, not neces- 1983; Singer, 1986; Moncalvo et al., 2002; Aime sarily differentiated terminal elements, can be et al., 2005). The limits between Simocybe and found. Even in species like C. cristulatus Crepidotus have been (until recently) defined Singer, C. rubriceps Singer and the other new artificially to some extent by having been based species herein proposed (see below), the pilei- exclusively on a reduced number of species of pellis has more defined terminal elements, each genus for comparison. It is not surprising resembling cystidia-like structures in compari- 18