A Contribution to the Taxonomy of Rhizochaete (Polyporales, Basidiomycota)

Abstract

Rhizochaete is a small genus of crust fungi that is closely related to Phanerochaete. A new species Rhizochaete belizensis is described, and three new combinations are proposed. Morphological studies and molecular sequence data from two nuclear ribosomal DNA regions (ITS and LSU) support the recognition of R. belizensis which is closely related to R. radicata. Analyses of sequence data also support the transfer of Phanerochaete flava to Rhizochaete. Phanerochaete percitrina from Cameroon and Peniophora rhizomorpho-sulphurea from India are transferred to Rhizochaete based on morphological studies of type specimens. Phanerochaete rubescens from Taiwan is placed in synonymy under R. borneensis. In addition, Phanerochaete mauiensis is redescribed and illustrated. A key to 13 accepted species of Rhizochaete and three morphologically similar species is presented.

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A Contribution to the Taxonomy of Rhizochaete
(Polyporales, Basidiomycota)
Author(s): Karen K. Nakasone, Kymberly R. Draeger & Beatriz Ortiz-
Santana
Source: Cryptogamie, Mycologie, 38(1):81-99.
Published By: Association des Amis des Cryptogames
DOI: http://dx.doi.org/10.7872/crym/v38.iss1.2017.81
URL: http://www.bioone.org/doi/full/10.7872/crym/v38.iss1.2017.81
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Cryptogamie, Mycologie, 2017, 38 (1): 81-99
©2017 Adac. Tous droits réservés
doi/10.7872/crym/v38.iss1.2017.81
Acontribution to the taxonomy of Rhizochaete
(Polyporales, Basidiomycota)
Karen K. NAKASONEa*,Kymberly R. DRAEGER b&Beatriz ORTIZ-SANTANAa
aCenter for Forest Mycology Research, Northern Research Station,
U.S. Forest Service, One GiffordPinchot Drive, Madison, WI, 53726, U.S.A.
bDepartment of Forest and Wildlife Ecology,University of Wisconsin-Madison,
Madison, WI, 53706, U.S.A.
Abstract –Rhizochaete is asmall genus of crust fungi that is closely related to Phanerochaete.
Anew species Rhizochaete belizensis is described, and three new combinations are proposed.
Morphological studies and molecular sequence data from two nuclear ribosomal DNA regions
(ITS and LSU) support the recognition of R. belizensis which is closely related to R. radicata.
Analyses of sequence data also support the transfer of Phanerochaete ava to Rhizochaete.
Phanerochaete percitrina from Cameroon and Peniophora rhizomorpho-sulphurea from
India are transferred to Rhizochaete based on morphologicalstudies of type specimens.
Phanerochaete rubescens from Taiwan is placed in synonymy under R. borneensis.In
addition, Phanerochaete mauiensis is redescribed and illustrated. Akey to 13 accepted
species of Rhizochaete and three morphologically similar species is presented.
Type studies /crust fungi /phlebia clade / Phanerochaetaceae
INTRODUCTION
Rhizochaete Gresl., Nakasone &Rajchenb. is asmall, distinctive genus of
crust fungi that produces hyphal cords and has aworld-wide distribution. Introduced
in 2004 with six species, it was distinguished from Phanerochaete P. Karst. by
morphological and molecular characters (Greslebin et al.,2004). Bianchinotti et al.
(2005) reported that Rhizochaete species have perforate septal dolipore caps or
parenthesomes. Recently,three species were transferred to Rhizochaete –
R.sulphurosa (Bres.) Chikowski, K.H. Larss. &Gibertoni, R. sulphurina (P.Karst.)
K.H. Larss., and R. violascens (Fr.:Fr.)K.H. Larss. (Chikowski et al.,2016a, b).
Phylogenetic studies place Rhizochaete in the Phanerochaete clade (Floudas
&Hibbett, 2015) or the Phanerochaetaceae Jülich (Miettinen et al.,2016). Depending
on the regions sequenced and the species of Rhizochaete and closely related taxa
included in the study, Rhizochaete is shown to be amonophyletic or paraphyletic
genus. For example, Rhizochaete,represented by four species, is monophyletic in
Floudas &Hibbett’s(2015, Fig. 1) multigene phylogenetic analyses of the
Phanerochaete clade. In analysis of the ITS sequences of the Phlebiopsis subclade,
however, Rhizochaete is paraphyletic because Hapalopilus rutilans (Pers.) Murrill is
*Corresponding author: knakasone@fs.fed.us

82 K. K. Nakasone et al.
included with six Rhizochaete species (Floudas &Hibbett 2015, Fig. 3). Chikowski
et al. (2016a) resolved Rhizochaete as monophyletic in the phylogenetic analyses of
ITS sequence data that included six Rhizochaete species. However,with the LSU
sequence dataset that included eight Rhizochaete species, the genus was recovered
in two clades of an unresolved three-way polytomy.The two clades included the
following taxa: (1) Rhizochaetebrunnea Gresl., Nakasone &Rajchenb. R. fouquieriae
(Nakasone &Gilb.) Gresl., Nakasone &Rajchenb., and R.radicata (Henn.) Gresl.,
Nakasone &Rajchenb. and (2) R. americana (Nakasone, C.R. Bergman &Burds.)
Gresl., Nakasone &Rajchenb., R. lamentosa (Berk. &M.A. Curtis) Gresl.,
Nakasone &Rajchenb., R. sulphurina, R. sulphurosa, R. violascens, and Phlebiopsis
roumeguerii (Bres.) Jülich &Stalpers. In contrast, in acombined ITS and LSU
analyses by Miettinen et al. (2016, Fig. 2), seven species of Rhizochaete were
included in anine-way polytomy in the Phlebiopsis clade along with species of
Hapalopilus P. Karst., Phlebiopsis Jülich, Phaeophlebiopsis D. Floudas &Hibbett,
Phlebia unica (H.S. Jacks. &Dearden) Ginns, and Phanerochaete lutea (Sheng
H. Wu)Hjortstam. With the addition of rpb1 sequences, however, Rhizochaete
(represented by three species) was resolved as adistinct subclade within the
Phlebiopsis clade (Miettinen et al.,2016, Fig. 3).
In this paper,wedescribe anew species of Rhizochaete from Belize and
transfer three additional species to the genus based on morphological and molecular
data. The circumscription of Rhizochaete is modied slightly to accommodate the
variation observed among the species. Rhizochaete borneensis (Jülich) Gresl.,
Nakasone &Rajchenb. and Phanerochaete mauiensis Gilb. &Adask., which have
features found in Rhizochaete,are redescribed and illustrated. Phanerochaete
rubescens Sheng H. Wu,from Taiwan, is placed in synonymy under R. borneensis.
Akey to 13 accepted species in the genus and three morphological similartaxa is
presented.
MATERIALS AND METHODS
Morphological studies
Thin, freehand sections from basidiomes were mounted in adrop of aqueous
potassium hydroxide, KOH, (2% w/v) and aqueous phloxine (1% w/v) or Melzer’s
reagent (Kirk et al., 2008) and examined with an Olympus BH2 compound
microscope. Drawings were made with acamera lucida attachment. Cyanophily of
basidiospore and hyphal walls was observed in 0.1 %cotton blue in 60% lactic acid
(Kotlaba &Pouzar,1964; Singer,1986). Average, ›,basidiospore measurements
were calculated from at least 30 spores, and standard deviations are given if only
one specimen was measured. Standard deviations are omitted if the average of more
than one specimen was calculated; number of specimens measured is given in
parentheses. Qvalues were obtained from dividing average basidiospore length by
width of at least 30 spores (Kirk et al., 2008). Capitalized color names are from
Ridgway (1912), and color codes follow Kornerup &Wanscher (1978). Herbarium
code designations are from Index Herbariorum (Thiers, 2016). MycoBank (Robert
et al.,2013) and Index Fungorum (www.indexfungorum.org) were consulted
frequently throughout this study.

Acontribution to the taxonomy of Rhizochaete (Polyporales, Basidiomycota) 83
Molecular studies
Four new ITS and one LSU sequences were generated, and 29 ITS and
25 LSU sequences of Rhizochaete species and related species of Phaeophlebiopsis
D. Floudas &Hibbett, Phanerochaete,Phlebiopsis, and Phlebia unica were retrieved
from GenBank (Benson et al.,2013). We consulted Floudas &Hibbett (2015) and
Chikowski et al. (2016a) to identify taxa in the Phanerochaetaceae to include in the
dataset. Byssomerulius corium (Pers.) Parmasto, amember of the Byssomerulius
clade and sister to the Phanerochaete clade (Floudas &Hibbett 2015) was used as
the outgroup taxon. The information for these sequences is provided in Table 1.
DNA extraction, amplication and sequencing followed Palmer et al. (2008). The
ITS region was amplied with primers ITS1F (Gardes &Bruns, 1993) and ITS4
(White et al.,1990). Sequences were edited with Sequencher 4.8 (Gene Codes
Corp., Ann Arbor,Michigan). Newly generated sequences were deposited in
GenBank (KY273029-KY273033), and the alignment was deposited in TreeBASE
(SN20273). DNA sequences were aligned with MAFFT 7(Katoh &Standley,2013).
The Q-INS-I algorithm was used to align the ITS sequences whereas the G-INS-I
algorithm was used for LSU sequences. Final adjustments to the alignment were
done manually with MacClade 4.08 (Maddison &Maddison, 2002). Phylogenetic
analyses of the ITS and LSU dataset alone as well as acombined ITS+LSU dataset
were performed using maximum likelihood (ML) and Bayesian (BY) methods.
Maximum likelihood analysis was performed using RAxML black box (Stamatakis
et al.,2008) under the GTR model with GAMMA distributed rate heterogeneity and
100 rapid bootstrap replicates. Bayesian analysis was performed using MrBayes
3.2.6 (Ronquist et al.,2012) on XSEDE through the CIPRES Science Gateway
(Miller et al.,2010) for 3000 000 generations in two runs and four chains with trees
sampled every 1000 generations. The burn-in period was set to 0.25. Strong support
values of clades are >90% in ML and >0.95 posterior probabilities (PP) in BY
analyses whereas moderate support values are >65% and >0.90, respectively.
RESULTS
Phylogenetic analyses
The combinedITS+LSU nrDNA dataset consisted of 34 ingroup sequences
with atotal of 1560 characters (ITS 658 characters, LSU 902 characters), including
10 of the 13 Rhizochaete species. There were ITS and LSU sequences for nine
Rhizochaete species, excepting R.violascens with only LSU. The tree topologies
obtained from the ML and BY analyses differed only with lamentosa and the ava/
sulphurina clades switching positions. The BY topology is presented in Figure 1. In
this tree, Rhizochaete was recovered in two clades with nine taxa in astrongly
supported core clade and R. violascens with three species of Phaeophlebiopsis in a
weakly supported sister clade. Within the core Rhizochaete lineage,three well-
supported subclades were obtained: (1) the sulphurosa/americana/sulphurina/ava
clade, (2) the radicata/belizensis/brunnea/fouquieriae clade, and (3) the lamentosa
clade. In the ML tree (not shown), however,the Rhizochaete core clade had moderate
support (68%) with the ava/sulphurina subclade moderately supported (71%)
compared to the sulphurosa/americana/lamentosa and the radicata/belizensis/
brunnea/fouquieriae subclades that had weak or no support.

84 K. K. Nakasone et al.
Table 1. Taxa included in the phylogenetic study with voucher,locality,and GenBank accession
numbers
Species Isolate no. Locality
Country: State
GenBank accession no.
ITS LSU
Phaeophlebiopsis caribbeana FD442 USA: Virgin Islands* KP135416 –
HHB-6990 USA: Florida KP135415 KP135243
Phaeophlebiopsis ignerii FD425 USA: Virginia KP135418 –
Phaeophlebiopsis peniophoroides FP150577 USA: Hawaii KP135417 KP1352730
Phanerochaete afnis KHL11839 Sweden EU118652 EU118652
Phanerochaete conifericola OM7749-7 Finland KP135173 –
Phanerochaete ericina HHB2288 USA: North Carolina KP135167 KP135247
Phanerochaete laevis FD206 USA: Massachusetts KP135152 –
HHB15519 USA: Alabama KP135149 KP135249
Phanerochaete rhodella FD18 USA: Massachusetts KP135187 KP135258
Phanerochaete velutina LE298547 Russia KP994360 KP994385
Phlebia unica KHL11786 Sweden EU118657 EU118657
Phlebiopsis crassa KKN86 USA: Arizona KP135394 KP135215
MAFF420737 Japan AB809163 AB809163
Phlebiopsis avidoalba KHL13055 Costa Rica EU118662 EU118662
Phlebiopsis gigantea FBCC315 Finland LN611131 LN611131
Rhizochaete americana FP102188 USA: Illinois KP135409 KP135277
HHB2004 USA: Georgia AY219391 AY219391
Rhizochaete belizensis FP150712 Belize KP135408 KP135280
Rhizochaete brunnea MR11455 Argentina AY219389 AY 219389
Rhizochaete lamentosa FP105240 USA: Indiana KP135411AY219393
HHB3169 USA: Maryland KP135410 KP135278
Rhizochaete ava PR3148 Puerto Rico KY273029 –
PR1141 Puerto Rico KY273030 KY273033
Rhizochaete fouquieriae KKN121 USA: Arizona AY219390 GU187608
Rhizochaete radicata FD123 USA: Massachusetts KP135407 KP135279
FD338 USA: Massachusetts KP135406 –
HHB1909 USA: North Carolina AY219392 AY219392
Rhizochaete sulphurina DLL2014-176 USA: Idaho KY273032 –
HHB5604 USA: Montana KY273031 GU187610
Rhizochaete sulphurosa KHL16087 Brazil KT003523 –
URM85028 Brazil KT003521 KT003517
URM87190 Brazil KT003522 KT003519
Rhizochaete violascens KHL11169 Norway –EU118612
Byssomerulius corium FP102382 USA: Wisconsin KP135230 KP135007
*U.S. Virgin Islands is aU.S. Territory.

Acontribution to the taxonomy of Rhizochaete (Polyporales, Basidiomycota) 85
With ITS sequences alone, Rhizochaete was recovered as astrongly
supported monophyletic genus by ML and BY analyses, 96% and 0.96, respectively,
but the Phlebiopsis clade was paraphyletic (trees not shown). In comparison, analyses
of the LSU dataset found the Phlebiopsis clade moderately supported (70%) with
ML analysis or strongly supported (0.99) with BY analysis but resolved Rhizochaete
as paraphyletic in clades with little or no support (trees not shown).
Taxonomy
Rhizochaete Gresl., Nakasone &Rajchenb., emended
Basidiome effused, loosely adnate, pellicular to membranous, fragile,
readily detached; hymenial surface smooth to tuberculate, yellow,orange, brown,
olivaceous or violaceous,usually turning red to purple in KOH solution, occasionally
with no reaction or turning dark brown;margin mbriate to brillose, often with
hyphal cords that typically turn red to violet in KOH but sometimes with no reaction.
Hyphal system monomitic; generative hyphae regularly clamped or primarily simple-
septate with scattered clamps. Subiculum composed of non-agglutinated, loosely
Fig. 1. Bayesian consensus tree based on combined ITS+LSU nrDNA sequences. Support values along
branches are from Maximum likelihood bootstrap (≥65%) and Bayesian analyses (PP ≥0.95),
respectively.Adash indicates ML bootstrap value <65%. Generic types are indicated by an asterisk (*)
and new species is highlighted.

86 K. K. Nakasone et al.
arranged hyphae often encrusted with small, discrete, insoluble crystal clusters and
coated with small, particulate, yellow,resinous-like material that dissolves readily
in KOH. In one species (R. percitrina)with large masses of yellow,resinous-like
material that dissolves readily in KOH embedded in trama. Cystidia usually present,
cylindrical to subfusiform, thin to thick-walled, encrusted or smooth.Basidia clavate
to subcylindrical, 4-sterigmate. Basidiospores cylindrical to ellipsoid, up to 6 ×
4µm, walls hyaline, thin to slightly thickened, smooth, acyanophilous, not reacting
to Melzer’s reagent. On wood and bark of angiosperms and gymnosperms, associated
with awhite rot-decay.
Typus: Rhizochaetebrunnea Gresl., Nakasone &Rajchenb.
The circumscription of Rhizochaete is slightly modied (indicated by
italicized text) to include variation observed in the basidiome and hyphal cord reaction
to KOHsolution and the distribution and form of the resinous-likematerial in the
context. Consult Greslebin et al. (2004) for amore detailed description and discussion
of the genus. In the key below, Phanerochaete galactites (Bourdot&Galzin) J. Erikss.
&Ryvarden, Ceraceomyces cystidiatus (J. Erikss. &Hjortstam) Hjortstam, and
P. mauiensis are included for they resemble some species of Rhizochaete.
Key to the species of Rhizochaete and similar taxa
1. Hyphae primarily simple-septate with scattered clamps .....................................2
1. Hyphae regularly clamped..................................................................................12
2. Cystidia with thin or slightly thickened walls, <1µmthick.......................3
2. Cystidia with distinctly thick walls, >1µmthick........................................8
3. Hymenium turning purple, pink or red in KOH..................................................4
3. Hymenium not reacting or darkening to orange or brown in KOH...................5
4. Subiculum yellow,cystidia 30-45 ×4-5.5 µm......................... R. sulphurosa
4. Subiculum brown, cystidia 30-60 ×5-7 µm............................ R. lamentosa
5. Basidiomes white, cream to yellowish brown, hyphal cords white, basidiospores
2-2.5 µmdiam ..............................................................Phanerochaete galactites
5. Basidiomes yellow to brownish orange, hyphal cords yellow to yellowish brown,
basidiospores 2.2-3.6 µmdiam.............................................................................6
6. Basidiomes bright yellow,unchanged in KOH, basidiospores 2.2-3 µm
broad, from Central Africa .........................................................R. percitrina
6. Basidiomes yellow to brownish orange, darkening in KOH, basidiospores
2.8-3.6 µmbroad ............................................................................................7
7. Basidia 30-40 µmlong, basidiospores 3.8-4.7 µmlong, from India....................
....................................................................................... R. rhizomorphosulphurea
7. Basidia 15-25 µmlong, basidiospores 4.3-5.8 µmlong, from Central and South
America......................................................................................................R. ava
8. Cystidia usually <50µmlong ......................................................................9
8. Cystidia usually >50µmlong ....................................................................10
9. Basidiomes red in KOH, cystidia heavily encrusted with hyaline crystals, from
Asia....................................................................................................R. borneensis
9. Basidiomes unchanged in KOH, cystidia smooth, from Africa .......R. percitrina
10. Basidiomes cream to buff, hyphal cords absent....Phanerochaete mauiensis
10. Basidiomes dull orange, dull yellow,oryellowish brown, hyphal cords
present...........................................................................................................11

Acontribution to the taxonomy of Rhizochaete (Polyporales, Basidiomycota) 87
11.Subiculum mustard yellow to brown, cystidia usually >60µmlong, spores
>4µmlong, found worldwide ...........................................................R. radicata
11.Subiculum yellow,cystidia usually <60µmlong, spores <4µmlong, from
Belize..................................................................................................R. belizensis
12. Cystidia absent or rare................................................................ R. violascens
12. Cystidia abundant .........................................................................................13
13. Cystidia cylindrical, up to 250 µmlong with thick walls, basidia 40-60 µmlong,
from Argentina ......................................................................................R. brunnea
13. Cystidia up to 100 µmlong with thin walls, basidia ≤40 µmlong ................14
14. Basidiospores 3-4 µmbroad, from southern Arizona ............. R. fouquieriae
14. Basidiospores usually ≤3µmbroad ...........................................................15
15. Basidiomes dingy white to violaceous, from North Europe .................................
.......................................................................................Ceraceomyces cystidiatus
15. Basidiomes yellow,brown, or olive brown .......................................................16
16. Basidiomes olive brown to yellowish brown, cystidia ≤60 µmlong, from
eastern North America................................................................R. americana
16. Basidiomes bright to dull yellow,cystidia >60µmlong, from western North
America and North Europe ........................................................R. sulphurina
Species descriptions
Rhizochaete belizensis Nakasone, K. Draeger &B.Ortiz, sp. nov. Fig. 2
MycoBank no.:MB818007
Diagnosis:Rhizochaete belizensis is most similar to R. radicata but differs
in having shorter basidiospores, average size 3.5-3.6 ×2.5-2.6 µm, and shorter
cystidia, usually <60µmlong.
Type:Belize, Cayo District, Blue Hole National Park, Hummingbird Loop
Trail, on decorticate hardwood, 15 November 2001, K.K. Nakasone, FP150712
(holotype CFMR). GenBank accession numbers: KP135408 (ITS) and KP135280
(LSU). Basidiome resupinate, widely effused, loosely adnate, up to 700 µmthick,
pellicular,soft, fragile, with hyphal cords; hymenial surface smooth, fragile, readily
aking off, orange white (5A2), turning violaceous, Pale Pinkish Buff, or Light Buff
in KOH; context byssoid, white next to substrate, then light yellow [3A(4-5)],
Lemon Chrome or Strontium Yellow just under hymenium; margin adnate, thinning
out, subfelty,sterile, darker than hymenium, orange grey (5B2) or Chamois,
becoming cordonic. Hyphal cords up to 2mmdiam, dark mustard yellow,yellowish
brown (5D8), or brown (6D7), turning violaceous in KOH.
Hyphal system monomitic; generative hyphae simple-septate with rare
single clamps. Subiculum up to 600 µmthick, an open, non-agglutinated, loosely
interwoven tissue; subicular hyphae 3.5-7 µmdiam, occasionally ampullate up to
9µmdiam, simple-septate with rare, single clampconnections, moderately branched,
sometimes with H-connections, walls hyaline, thin to 2.2 µmthick, heavily coated
with small, particulate, yellowish brown material that readily dissolves in 2% KOH
and encrusted with coarse, insoluble hyaline crystals. Subhymenium up to 70 µm
thick, amoderately dense, non-agglutinated tissue of upright, short-celled hyphae,
subhymenial hyphae 3-5 µmdiam, simple-septate, much branched, walls hyaline,
thin, coated with small, particulate, yellowish brown material that readily dissolves
in KOH. Hymenium up to 60 µmthick, adense palisade of cystidia and basidia.

88 K. K. Nakasone et al.
Cystidia subfusiform, rarely clavate, with asubacute or obtuse apex, 40-60(-75) ×
8-9.5 µm, up to 13 µmdiam including crystals, simple-septate at base, protruding
or enclosed, sometimes with secondary septa, walls hyaline,slightly thickened or up
to 2.2 µmthick, upper half lightly to heavily encrusted with hyaline, insoluble
crystals. Basidia narrowly clavate, 17-25 ×4.2-5.5(-5.8) µm, simple-septate at
base, 4-sterigmate, walls hyaline, thin, coated with particulate, yellowish brown
material that readily dissolves in 2% KOH. Basidiospores ellipsoid to broadly
ellipsoid, (2.9-)3-4(-4.2) ×2.2-3 µm, ›(2) =3.5-3.6 ×2.5-2.6 µm, Q=1.3-1.5,
walls hyaline, thin, smooth, acyanophilous, not reacting in Melzer’s reagent.
Habitat and distribution:Onbark and wood of angiosperms in Belize.
Additional specimens examined: Belize, Cayo District, Mountain Pine
Ridge, Five Sisters Lodge, along Nature Trail, on decayed hardwood, 19 November
2001, K.K. Nakasone, FP150806 and FP150811(CFMR).
Fig. 2. Rhizochaete beliziensis
(FP150806, paratype). A. Basi-
diospores. B. Basidia. C. Cysti-
dia. D. Basidiome with hyphal
cords (from FP150811, para-
type). Scale bar =20mm.

Acontribution to the taxonomy of Rhizochaete (Polyporales, Basidiomycota) 89
Rhizochaete belizensis is characterized by afragile, soft, pale-colored
basidiome with mustard yellow hyphal cords, simple-septate generative hyphae,
thick-walled subfusiform cystidia, and small, broadly ellipsoid basidiospores.
Compared to R. belizensis, R. radicata has typically longer basidiospores, 3.5-5 µm
long, and longer cystidia, 60-100(-115) µmlong, whereas R. borneensis,from Asia,
has slightly larger basidiospores, 4-5 ×2.8-3.2 µm. Sequence analyses of the
combined ITS and LSU show that R. belizensis is adistinct species that is sister to
R. radicata (Fig. 1). Floudas &Hibbett (2015) were the rst to show that R. belizensis,
as Rhizochaete sp. FP150712, was closely related to R. radicata in their ITS and
multigene analyses.
Rhizochaete borneensis (Jülich) Gresl., Nakasone &Rajchenb., Mycologia 96: 267
(2004) Fig. 3
=Phanerochaete rubescens Sheng H. Wu, Mycological Research 102: 1131
(1998). Basidiomes resupinate, effused, thin, soft, membranous to pellicular;
hymenial surface smooth, greyish yellow [4B(4-5)], turning red-violet in KOH;
context tomentose, bright orange yellow (4A7); margin adnate with bright orange
yellow (4A7) hyphal cords, turning red-violet in KOH.
Hyphal system monomitic; generative hyphae simple-septate with rare
single clamps. Subiculum aloosely organized, non-agglutinated tissue; subicular
Fig. 3. Phanerochaete bor-
neensis (Jülich78-2157,
holotype). A. Basidiospores.
B. Basidia. C. Cystidia.
D. Subicular hyphae.

90 K. K. Nakasone et al.
hyphae 2-5 µmdiam, simple-septate, moderately branched, sometimeswith
H-connections, walls hyaline, thin to slightly thickened, coated with small, yellow
material that dissolves in KOH. Subhymenium slightly thickened. Hymenium a
palisade of cystidia and basidia. Cystidia enclosed or slightly protruding, subfusiform
to conical with an obtuse apex, 20-35(-50) ×7-8 µm, up to 12 µmdiam including
encrustations, simple-septate at base, walls hyaline,slightly thickened, encrusted at
apex or upper half with coarse, insoluble, hyaline crystals, sometimes slightly
dextrinoid. Basidia clavate to broadly cylindrical, (16-)20-30(-37) ×5-8 µm, simple-
septate at base, 4-sterigmate, walls hyaline, thin to slightly thickened, smooth.
Basidiospores broadly ellipsoid, 4-5 ×2.8-3.3 µm, walls hyaline,thin to slightly
thickened, smooth, not reacting in Melzer’s reagent.
Habitat and distribution:Ondecayed wood in Borneo and Taiwan.
Type specimen examined:Malaysia, Borneo, Sarawak State, Gunung Mulu
National Park, Camp 1, 16 March 1978, W. Jülich 78-2157 (L, holotype).
Descriptions:Jülich (1980), Wu (1998, as P. rubescens).
Rhizochaete borneensis is characterized by agrayish yellow basidiome and
yellow hyphal cords that turn red to violet in KOH, simple-septate hyphae, short,
thick-walled, encrusted cystidia, and broadly ellipsoid basidiospores. Rhizochaete
radicata is similartoR. borneensis but has longer cystidia, (40-)60-100(-115) µm
long and slightly narrower basidiospores, 2.2-3 µmdiam. In contrast, the cystidia in
R. percitrina,from Cameroon, are short and thick-walled but smooth. Although we
were not able to examine the holotype of P. rubescens,asdescribed by Wu (1998),
it is morphologically indistinguishable from R. borneensis.Inaddition, these taxa
occur in the same subtropical-tropical region of Asia.
Rhizochaete ava (Burt) Nakasone, K. Draeger &B.Ortiz, comb.nov.
MycoBank no.:MB818015
≡Coniophora ava Burt, Annals Missouri Botanical Garden 4: 261 (1917).
≡Peniophora ava (Burt) D.P.Rogers &H.S. Jacks., Farlowia 1: 278
(1943). ≡Phanerochaete ava (Burt) Nakasone, Burds. &Lodge, Mycologia 90:
132 (1998).
Basidiospores ellipsoid to narrowly ellipsoid, 4.3-5.5(-5.8) ×2.8-3.2 µm,
›=4.8 ±0.4 ×3±0.1 µm, Q=1.6 ±0.1, walls hyaline,thin, smooth, acyanophilous,
not reacting in Melzer’s reagent.
Specimens examined:Puerto Rico, Rio Grande Municipio, Luquillo
Mountains, Caribbean National Forest, El Verde Research Area, trail to Sonadora,
on decorticate hardwood branch, 20 May 1993, D.J. Lodge, M. Boyd, &L.Fish,
PR1141 (CFMR); log on ground, 4June 1998, K.K. Nakasone, FP150195 (CFMR).
Isabela Municipio, Guajataca Commonwealth Forest, First camp, Verada Nueva
Trail, on decayed branch, 22 January 1996, D.J. Lodge &M.Harrington, PR3148
(CFMR).Description and illustration:Nakasone et al. (1998).
Rhizochaete ava is atypical member of this genus except that its hymenium
and hyphal cords do not turn red or purple in KOH but darken to brown instead.
Molecular data also support the transfer of R. ava into Rhizochaete where it is
in aclade with R.sulphurosa and R.sulphurina (Fig. 1). It can be confused
with R. sulphurosa which has similar basidiome and basidiospore features, but
R. sulphurosa has narrower cystidia, 4-6 µmdiam, and hymenium and hyphal cords
that turn purple in KOH.

Acontribution to the taxonomy of Rhizochaete (Polyporales, Basidiomycota) 91
Multiple attempts were made to sequence the ITS of different R. ava
strains, but only PR3148 was successful. The previous ITS sequence of R. ava in
GenBank (AY219358) by de Koker et al. (2003) was based on amix-up of the
specimen and culture, PR-3147, which is Microporellus obovatus (Jungh.) Ryvarden.
Rhizochaete percitrina (P.Roberts &Hjortstam) Nakasone, comb.nov.Fig. 4
MycoBank no.:MB818016
≡Phanerochaete percitrina P. Roberts, Kew Bulletin 55: 821 (2000).
Basidiome effused, thin, up to 250 µmthick, loosely adnate, fragile, soft,
pellicular to membranous with hyphal cords; hymenial surface smooth to farinaceous,
pale yellow (3A3), light yellow [(2-3)A(4-5), 4A(4-5)] with scattered light orange
(5A4) areas, no color change in KOH; margin appressed, brillose to cordonic,
concolorous with hymenium, no color change in KOH.
Hyphal system monomitic; generative hyphae simple-septate. Subiculum up
to 200 µmthick, anon-agglutinated tissue of loosely arranged hyphae, more or less
Fig. 4. Phanerochaete
percitrina (K(M)
50164, holotype).
A. Basidiospores.
B. Basidia. C. Cysti-
dia with thickened
walls. D. Cystidia
withthinwalls
(from K(M)50165,
paratype). E. En-
crusted subicular
hypha. F. Basidiome
with hyphal cords.
Scale bar =20mm.

92 K. K. Nakasone et al.
parallel to substrate, and large masses of dark yellow,resinous-like material that
dissolves in KOH; subicular hyphae 2.5-5 µmdiam, sometimes inating up to 7 µm
at septa, simple-septate, sparsely to moderately branched, often developing
H-connections, walls hyaline, thin to 1.5 µmthick, smooth to heavily encrusted with
small, discrete clusters of insoluble, hyaline crystals. Subhymenium slightly
thickening, up to 40 µmthick, acompact, non-agglutinated tissue of short-celled,
upright hyphae; subhymenial hyphae 2.2-4.5 µmdiam, simple septate, moderately
branched, walls hyaline, thin, smooth. Hymenium up to 40 µmthick, adense palisade
of cystidia and basidia. Cystidia inconspicuous, cylindrical to subfusiform, rarely
moniliform, occasionally with one or more adventitious septa, 22-35 ×3.5-6 µm,
simple septate at base, enclosed or protruding up to 15 µm, walls hyaline,thin or
up to 1 µmthick toward base, smooth. Basidia narrowly clavate, often slightly
constricted, usually with adistinct stalk, 23-30 ×4.3-5.8 µm, simple-septate at base,
walls hyaline,thin or up to 0.7 µmthick at base, smooth, 4-sterigmate. Basidiospores
ellipsoid, often containing asingle oil-like globule, 3.5-4.3 ×2.2-3 µm, ›(2) =3.7-
4.1 ×2.4-2.5 µm, Q=1.5-1.7, walls hyaline, thin, smooth, acyanophilous, not
reacting in Melzer’s reagent.
Habitat and distribution:Ondecayed wood in Cameroon.
Type specimen examined:Cameroon, South West Province, Korup National
Park, Science Camp, on rotten log, 3April 1997, P. Roberts K837, K(M)50164
(K, holotype).
Additional specimens examined:Cameroon, South West Province, Korup
National Park, trail to Rengo Rock, on rotten branch, 8April 1997, P.J. Roberts
K966, K(M)50165 (K); trail from Rengo Camp to Erat, on very rotten wood, 2May
1996, P.J. Roberts K380, K(M)58811(K).
Description and illustration: Roberts (2000).
Phanerochaete percitrina is characterized by fragile, bright yellow,
pellicular basidiomes with hyphal cords, subicular hyphae encrusted with small
clusters of hyaline crystals, cylindrical to subfusiform cystidia, and small, ellipsoid
basidiospores. There is some variation in the specimens cited above. For example,
Roberts (2000) described and illustrated cylindrical basidiospores, 3.5-4.5(-6) ×
2-2.5(-3) µm, Q=1.8-2.2, which are narrower than those observed in this study.
Distinctly thick-walled basidia and cystidia were observed in the holotype whereas
embedded, clavate cystidia were observed only in specimen K(M)50165.
Phanerochaete percitrina is transferred to Rhizochaete because of its
fragile, pellicular basidiomes, yellow hyphal cords, and small, ellipsoid basidiospores.
These are character traits found in most Rhizochaete species; however, R. percitrina
also displays characters that are unique or unusual in the genus. For example, in the
subiculum it produces large masses of dark yellow resinous-like material that
dissolves in KOH instead of tiny,yellow,resinous-like particles coating the hyphae
in other species of Rhizochaete.Unlike most species in the genus, R. percitrina and
R. ava do not develop encrusted cystidia nor do their hymenia turn red or purple
in KOH. Thick-walled basidia are present in R. brunnea and sometimes in
R. percitrina.Sequence data are needed to determine the phylogenetic relationship
between R. percitrina and other Rhizochaete species.
Rhizochaete rhizomorphosulphurea (B.K. Bakshi &Suj. Singh) Nakasone,
comb.nov.Fig. 5
MycoBank no.:MB818017
≡Peniophora rhizomorphosulphurea B.K. Bakshi &Suj. Singh, Indian
Forester 92: 567 (1966).

Acontribution to the taxonomy of Rhizochaete (Polyporales, Basidiomycota) 93
Basidiome resupinate, widely effused,5×2cm (isotypeatDAOM), up to
500 µmthick,membranous to subceraceouswhen fresh,ondrying becomingpellicular,
soft, fragile,readily cracking anddetachingfrom the substrate;hymenial surface
smooth, sulfur yellowwhen fresh then dryingtolight orange(5A2),greyish orange
(5B4),Light Ochraceous-Buff,Warm-Buff,Chamois, or Honey Yellow,turning
slightlydarkerinKOH;contextbyssoid,whitenext to substrate, then lightyellow
[3A(4-5)], LemonChrome or Strontium Yellow justunder hymenium; marginadnate,
thinning out, brillose to cordonic,white, yellowishwhite (4A2),pale yellow(4A3),
Maize Yellow, or CreamColor. Hyphal cords up to 800 µmdiam, light yellow(4A4)
to yellowishbrown (5D5),darkening to browninKOH,abundant in substrate and soil.
Fig. 5. Rhizochaeterhizomor-
phosulphurea (DAOM 02-
01000675859). A. Basidiospores
(from FRI7866, isolectotype).
B. Basidia. C. Cystidia. D. Cys-
tidium lacking encrustations
with slightly thickened walls.
E. Subicular hyphae. F. Basi-
diome with hyphal cords. Scale
bar =3mm.

94 K. K. Nakasone et al.
Hyphal system monomitic; generative hyphae simple-septate with scattered
single clampconnections. Subiculum up to 400 µmthick, an open, non-agglutinated,
loosely interwoven tissue; subicular hyphae 3.5-6 µmdiam, simple-septate with
scattered, single clamp connections, moderately branched, sometimes with
H-connections, occasionally slightly ampullate, walls hyaline, thin, heavily coated
with small, particulate, yellowish brown material that readily dissolves in 2% KOH
andencrustedwithsmall,discreteclustersofinsoluble, hyaline crystals. Subhymenium
up to 70 µmthick, amoderately dense, non-agglutinated tissue of upright hyphae;
subhymenial hyphae, 3-4.5 µmdiam, simple-septate, moderately branched, walls
hyaline, thin, coated with small, particulate, yellowish brown material that readily
dissolves in 2% KOH. Hymenium up to 45 µmthick, adense palisade of cystidia
and basidia. Cystidia clavate,subfusiform, or obclavate, with an obtuse apex,(25-)35-
50(-65) ×5.5-9 µm, up to 12 µmdiam including crystals, simple-septate at base,
slightly protruding, enclosed, or embedded, walls hyaline, thin to slightly thickened,
lightly to heavily coated with particulate, yellowish brown material that readily
dissolves in 2% KOH and encrusted with clusters of insoluble, hyaline crystals.
Basidia narrowly clavate to cylindrical, 30-40 ×5-6 µm, simple-septate at base,
4-sterigmate, walls hyaline, thin, coated with particulate, yellowish brown material
that readily dissolves in 2% KOH. Basidiospores ellipsoid to broadly ellipsoid, (3.8-)4-
4.5(-4.7) ×2.8-3.6 µm, ›(isolectotype) =4.2 ±0.2 ×3±0.2 µm, Q=1.4 ±0.1,
walls hyaline, thin, smooth, acyanophilous, not reacting to Melzer’s reagent.
Habitat and distribution:Reported on roots and stumps of teak in India,
Uttarakhand State; saprobic, possibly causing aroot rot.
Type specimen examined:India, Uttarakhand State, Dehr Dun (Dehradun),
Forest Research Institute, New Forest, on Tectona grandis L., 31 May 1966, FRI-
7866 (CFMR, lectotype designated here).
Additional specimen examined:India, Uttarakhand State, Dehr Dun
(Dehradun), Forest Research Institute, on roots of T. grandis,13August 1965,
B.K. Bakshi, DAOM95272-C (DAOM 02-01000675859).
Description and illustration:Bakshi et al. (1966).
Rhizochaete rhizomorphosulphurea is characterized by yellow to orange
basidiomes and hyphal cords that turn darker orange or brown in KOH, long basidia,
thin-walled cystidia, and ellipsoid basidiospores. Embedded cystidia are often
heavily encrusted whereas those in the hymenium may be smooth or only lightly
encrusted with clusters of insoluble hyaline crystals. It is not known if the color
change in KOH is atypical reaction or the result of age, for the specimens tested
are 50 years old. This species is most similar to R. ava which has shorter basidia
on average and slightly longer and narrower basidiospores. Their geographic
distributions are quite distinct —R.rhizomorphosulphurea is known only from
India and R. ava from subtropical and tropical America.
Rhizochaete rhizomorphosulphurea is accepted as adistinct species although
it is placed in synonymy under R. sulphurina in Index Fungorum and Mycobank.
Rhizochaete sulphurina differs from R. rhizomorphosulphurea in having primarily
clamped hyphae, larger cystidia, 40-90 ×10-12 µm, and slightly longer but narrower
basidiospores, (4.5-)5-5.8 ×2.5-3 µm.
The description above is based on observations of the specimens cited and
the original description by Bakshi et al. (1966). Aholotype was not designated; thus,
FRI-7866, one of the specimens citedinthe protologue, is designated the lectotype
of P. rhizomorphosulphurea.Vesicles reported by Bakshi et al. (1966) were not
observed and may be cytoplasmic materials escaping from broken or punctured
hyphal walls.

Acontribution to the taxonomy of Rhizochaete (Polyporales, Basidiomycota) 95
Phanerochaete mauiensis Gilb. &Adask., Mycotaxon 49: 384 (1993). Fig. 6
Basidiome resupinate, effused up to 20 cm, thin up to 180 µmthick,
adherent, rm, membranous to subceraceous, readily breaking apart; hymenial
surface smooth, pale yellow (4A3) to pale orange (5A3), not reacting to KOH;
margin thinning out, white, mbriate.
Hyphal system monomitic; generative hyphae simple-septate. Microbinding
hyphae absent or locally abundant in substrate, ≤0.7 µmdiam, aseptate, frequently
branched at right angles, walls hyaline, thin, smooth. Subiculum up to 75 µmthick,
composed of athin, dense layer of agglutinated hyphae arranged parallel to substrate
Fig. 6. Phanerochaete
mauiensis (JEA 1462, iso-
type). A. Basidiospores
(from RLG16784, para-
type). B. Basidia. C. En-
crusted cystidium. D. Mi-
crobinding hyphae. E. Ba-
sidiome (from RLG16784,
paratype). Scale bar =
3mm.

96 K. K. Nakasone et al.
(sometimes absent) then becoming upright, forming an open tissue of non-
agglutinated, loosely intertwined hyphae (sometimes absent); subicular hyphae 2.5-
5µmdiam, simple-septate, moderately branched, walls hyaline, thin to slightly
thickened, occasionally up to 1.5 µmthick, smooth to moderately encrusted with
small, insoluble, hyaline crystals. Subhymenium thickening, up to 80 µmthick, composed
of upright, closely packed, non-agglutinated, short-celled hyphae and embedded
cystidia; subhymenial hyphae 2.3-3.2 µmdiam, simple-septate, frequently branched,
walls hyaline, thin, smooth. Hymenium adense palisade of cystidia and basidia.
Cystidia numerous, cylindrical to subfusiform, 40-60(-80) ×6.5-10(-15) µm, stalk
2.2-3.5 µmdiam, embedded or protruding up to 35 µm, walls hyaline,slightly thick
to 1 µmthick in stalk, up to 2.2 µmthick in main body,heavily encrusted with
fused, insoluble, hyaline crystals. Basidia clavate, (20-)22-28 ×(4.5-)5-5.5(-6.5)
µm, simple-septate at base, walls hyaline, thin, smooth, 4-sterigmate. Basidiospores
ellipsoid to broadly cylindrical, (4.4-)5-5.8(-6.4) ×(2.8-)3-3.6 µm, ›(2) =5.2-5.4 ×
3.1 µm, Q=1.7, walls hyaline, thin, smooth, acyanophilous, not reacting in Melzer’s
reagent. Habitat and distribution:Onbark and wood of angiosperms, especially
branches, in Hawaii.
Type specimens examined:U.S.A., Hawaii, Maui County,Makawao District,
Hana Highway,mile 6, on bark and wood of Eugenia jambos L. twigs, 13 June
1990, J.E. Adaskaveg 1462 (BPI-802945, holotype; ARIZ-AN028779, isotype).
Additional specimens examined:U.S.A., Hawaii, Hawaii Island, South Hilo
District, Hilo, Hemmes residence, on bark of Trema occidentalis (L.) Blume, 18 June
1990, R.L. Gilbertson 16863 (ARIZ-AN030405). Maui, Makawao District, Hana
Highway,mile 6, on decorticate E. jambos,13June 1990, R.L. Gilbertson 16784
(ARIZ-AN030377).
Description and illustration:Gilbertson &Adaskaveg (1993).
Phanerochaete mauiensis is characterized by an agglutinated subiculum
with distinct,thin-walled hyphae, embedded, encrusted cystidia, and ellipsoid
basidiospores. Because microbinding hyphae are not distributed evenly and found in
one specimen only,itisbest to consider this species monomitic. In the original
description, Gilbertson &Adaskaveg (1993) described cylindrical spores, 5.5-6 ×
2.5-3 µm, which are narrower than observed in the specimens cited above. This
species is most similar to Phanerochaete exigua (Burt) Nakasone, Burds. &Lodge
from Mexico which has cylindrical basidiospores, 5-7 ×2.5-3 µm. See Liberta
(1968) for adescription of P. exigua.
Phanerochaete mauiensis is included here because it may be mistaken for
aspecies of Rhizochaete because of its pale orange-colored basidiome, mbriate
margins, and encrusted cystidia. However,itlacks critical features of the genus such
hyphal cords and the tiny,resinous-like material embedded in the context that
dissolves in KOH. Moreover,the agglutinated subicular tissue observed in some
specimens of P. mauiensis is absent in Rhizochaete.
DISCUSSION
Rhizochaete is awell-dened genus, based on morphological and molecular
characters, with aglobal distribution. It now contains 13 species including four taxa
discussed in this paper.The pellicular,loosely adnate, fragile, often brightly colored
basidiomes and hyphal cords are useful characters to distinguish Rhizochaete in the

Acontribution to the taxonomy of Rhizochaete (Polyporales, Basidiomycota) 97
eld. Most species of Rhizochaete have alimited geographic distribution except for
R. radicata.Microscopically,species are characterized by aloose, open, non-
agglutinated subiculum, cystidia, small ellipsoid basidiospores, and abundant, tiny
particles of resinous-like material coating the hyphae and hymenial elements. These
particles readily dissolve in KOH. Critical microscopic features for species
identication include presence or absence of clamp connections, wall thickness and
encrustation of cystidia, and shape and size of basidiospores. Basidiome and hyphal
cord reaction to KOH solution are important characters also. With the addition of
R. ava, R. percitrina,and R. rhizomorphosulphurea,the genus now includes species
in which the basidiome and hyphal cords do not result in ared-violet color change
in KOH. Furthermore, R. percitrina does not produce the tiny,particulate, resinous-
like material, instead the resinous-like material aggregate into large, amorphous
masses embedded in the subiculum.
The tiny,resinous-like particles that dissolve in KOH are not unique to
Rhizochaete.For example, Ginnsia viticola (Schwein.) Sheng H. Wu &Hallenb. has
similar particles throughout its pellicular,reddish gray to greenish gray basidiome,
but its large basidia and basidiospores, 8-12 ×4.5-5.5 µm, distinguish it from
Rhizochaete.Species of Phlebia and Mycoacia also produce these particles but
develop ceraceous basidiomes with dense, often agglutinated, subicular and
subhymenial tissues.
By morphological criteria, Rhizochaete is adistinct, well-characterized
genus but the molecular evidence is mixed. Phylogenetically,itisinthe
Phanerochaetaceae which includes four major groups –the Phanerochaete clade, the
Donkia clade, the Phlebiopsis clade, and the Bjerkandera clade (Miettinen et al.,
2016). Floudas &Hibbett (2015) also recovered these four clades. Rhizochaete is in
the Phlebiopsis clade that also includes the genera Phlebiopsis,Phaeophlebiopsis,
and Hapalopilus P. Karst.
In our study,weanalyzed the ITS and LSU datasets alone and together with
maximum likelihood and Bayesian methods. Although the ITS sequence analyses
always recovered Rhizochaete as amonophyletic genus with strong support, it was
sister to agroup of Phanerochaete species resulting in aparaphyletic Phlebiopsis
clade. The LSU sequences, in contrast, recovered Rhizochaete as paraphyletic in
clades with weak or no support but the Phlebiopsis clade remained intact. By
combining ITS and LSU datasets, the Phlebiopsis clade was recovered with
Rhizochaete paraphyletic with species divided between two sister clades. Nine
species of Rhizochaete (with both ITS and LSU sequences), including the generic
type, were in amoderately supported core Rhizochaete clade whereas R. violascens
clustered with species of Phaeophlebiopsis,Phlebiopsis,and P. unica in aclade with
weak or no support (Fig. 1). This was not unexpected since only LSU sequence was
available for R. violascens,and in LSU-based phylogenetic analyses, Rhizochaete is
usually resolved as aparaphyletic genus (Wu et al.,2010; Chikowski et al., 2016a;
this study) except in one instance (Greslebin et al. 2004).
With ITS sequence data alone, Rhizochaete was paraphyletic withH. rutilans
in aclade with R. americana (Floudas &Hibbett, 2015, Fig. 3). Other studies,
however,recovered Rhizochaete as monophyletic based on ITS sequences (Greslebin
et al.,2004; Chikowski et al., 2016a; this study). With the addition of rbp1(Miettinen
et al.,2016, Fig. 3) or rbp1and rbp2(Floudas &Hibbett 2015, Fig. 1) to the ITS
and LSU sequences, Rhizochaete,represented by three or four species, is resolved
as astrongly supported genus.
In summary,depending on the taxa and genes included in the analyses,
Rhizochaete is recoveredeither as amonophyletic clade (Greslebin et al.,2004;

98 K. K. Nakasone et al.
Chikowski et al., 2016a) or as paraphyletic or polytomic togetherwith H. nidulans,
Phanerochaete lutea,Phlebia unica,and several species of Phlebiopsis (Wu et al.,
2010; Binder et al., 2013; Floudas &Hibbett, 2015; Chikowski et al., 2016a;
Miettinen et al. 2016). It appears that the monophyly of Rhizochaete can only be
resolved with the sequencing of additional Rhizochaete taxa and gene regions.
Despite the conicting molecular phylogenetic studies, we believe that
there is sufcient morphological and molecular evidence to accept Rhizochaete as a
monophyletic genus. Additional morphological and molecular phylogenetic studies
of species in the genus as well as related taxa are required to determine the scope
and limits of Rhizochaete.Future studies should include sequences from rbp1in
addition to sequences of the ITS and LSU regions and include taxa such as
Phanerochaete galactites and Ceraceomyces cystidiatus to determine if they are
congeneric with Rhizochaete.
Acknowledgments. We thank the curators and staffatthe following herbaria for
arranging specimen loans: ARIZ, DAOM, K, L. Critical review of this manuscript by
Dr.Harold H. Burdsall, Jr.and Dr.D.Floudas’ advice on phylogenetic analyses are greatly
appreciated. Fieldwork in Belize in 2001 was made possible by agrant from the National
Science Foundation, Biodiversity Surveys and Inventories Program to Dr.T.J.Baroni, the
State University of New York, College at Cortland (DEB-0103621), in collaboration with
Dr.D.J. Lodge and the Center for Forest Mycology Research, Northern Research Station,
U.S. Forest Service. Dr.Lodge helped with logistical support for the eld work in Belize.
Individuals with government and nongovernmental agencies in Belize are kindly acknowledged
for their help and guidance: Hector Mai, John Pinelo, and Natalie Rosado of The Conservation
Division, Belize Forestry Department, Belmopan, and Celso Poot, Station Manager of the
Tropical Education Center in Belize.
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