Book of Abstracts (PDF) - International Mycological Association

IMC7 Tuesday August 13th Lectures
146 - Recent advances in molecular phylogeny of
temperate Hygrophoraceae and concordance with
morphology and ecology
A.E. Kovalenko 1* , J.-M. Moncalvo 2 , R. Vilgalys 2 , R.H.
Petersen 3 , K.W. Hughes 3 & D.J. Lodge 4
1 V. L. Komarov Botanical Institute, Russian Academy of
Sciences, 2 Prof. Popov Street, 197376, St. Petersburg,
Russia. - 2 Department of Botany, Duke University,
Durham, North Carolina, 27708, U.S.A. - 3 Department of
Botany, University of Tennessee, Knoxville, Tennessee,
37996-1100, U.S.A. - 4 Centr. for Forest Mycology
Research, USDA-FS, FPL PO Box 1377, Luquillo PR
00773-1377, U.S.A. - E-mail: alkov@AK3010.spb.edu
Phylogenetic relationships within Hygrophoraceae
(Basidiomycota) were studied using parsimony analysis of
nuclear LSU, ITS1-2 and SSU rDNA. The analysis
included 114 sequences (30 LSU; 23 SSU; and 61 ITS of
41 species) from Russia, the USA and Europe. For
comparisons, a phylogenetic reconstruction was also made
using morphological and ecological data (30 characters in
total). Results from the molecular analyses are largely
concordant with each other as well as with the analysis of
morphological end ecological data. However, the ITS
sequences varied too much between representatives of
different genera, so this region is most appropriate for
phylogenetic studies within genera of the Hygrophoraceae.
The results suggested that the Hygrophoraceae appears to
be monophyletic group. The family contains 9 separate
clades that support the following genera: Cuphophyllus,
Neohygrocybe, Camarophyllopsis, Humidicutis,
Gliophorus, Pseudohygrocybe, Hygrocybe,
Neohygrophorus and Hygrophorus. The taxonomic
position of some species should be reevaluated. Including
several representatives of the Tricholomataceae s.l. (i.e.
Omphalina) in the analysis demonstrated that some of them
may be related to the Hygrophoraceae and probably should
be transferred to this family. (This study was partly
supported by grants from Hesler Endowment Fund and
Russian Foundation for Basic Research).
147 - Biogeographical implications of Trichomycete
distributions
R. Lichtwardt
University of Kansas, Department of Ecology &
Evolutionary Biology, Lawrence, Kansas 66045, U.S.A. -
E-mail: licht@ku.edu
Known distributions of Trichomycetes worldwide fall into
several patterns depending upon their host types, habitats,
and host specificity. It is hypothesized that in all cases
autonomous dissemination of the gut fungi does not occur
except within boundaries of their immediate host
populations, and that dispersals over greater distances are
the result of particular active or passive mechanisms.
Examples of vicariant distributions of the symbionts in
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Book of Abstracts
both the Northern and Southern Hemispheres are
presented. The hypothesis that this fungus-arthropod
association is very ancient is supported by historical
biogeography.
148 - Progress toward a rDNA based phylogeny of the
Harpellales
M.M. White
University of Kansas, Dept. Ecology and Evolutionary
Biology, Lawrence, Kansas 66045, U.S.A. - E-mail:
trichos@ku.edu
The Harpellales (Trichomycetes), gut fungi, are unique
endosymbionts associated with larval aquatic insects
worldwide. Their evolutionary relationships have been
difficult to infer because of the paucity of morphological
characters and unculturability of most of the 35 known
genera. Previous DNA studies have included at most four
genera of culturable Harpellales. This study used thalli
taken from guts (mixed genomic template) to generate 18S
and 28S rDNA sequences to infer the phylogeny of the
Harpellales using cladistic analyses. Sixteen genera of
Harpellales were included, with 64 of 72 sequences from
unculturable samples. The genus Orphella fell outside an
otherwise monophyletic group of Harpellales, more closely
allied to the Kickxellales. The two largest genera, Smittium
and Stachylina, are polyphyletic, perhaps masked by
convergent and limited morphological characters. The
cladograms did not reveal any pattern that corresponds
with the two most important morphological criteria,
trichospore shape and zygospore type, as well as
appendage number for both. The current two family system
of classification is not supported, suggesting that the
Legeriomycetaceae may need to be dropped as a rank.
However, the need to add more sequence data, pursuit of a
protein gene, and continued collections for subsequent
cladistic analyses are discussed.
149 - Systematics of non-culturable orders of
Trichomycetes based on molecular markers
M.J. Cafaro
University of Kansas, Dept. Ecology and Evolutionary
Biology, Lawrence, Kansas 66045, U.S.A. - E-mail:
matcaf@ku.edu
The Eccrinales and Asellariales are morphologically
diverse orders of the class Trichomycetes (Zygomycota).
These gut fungi inhabit a wide range of hosts: Crustacea,
Insecta and Diplopoda in varied habitats (marine,
freshwater and terrestrial). The order Eccrinales is
characterized by unbranched, nonseptate, multinucleate
thalli and sporangiospores that are formed basipetally from
the thallus apex; they live attached to the cuticle lining of
the digestive tract of the host by a secreted, basal holdfast.
The order Asellariales, on the contrary, has branched,