Book of Abstracts (PDF) - International Mycological Association

IMC7 Main Congress Theme II: SYSTEMATICS, PHYLOGENY AND EVOLUTION Posters
species growing in Cameroon was done by Heim in 1952
and the author reported just 8 species in his account. A
field study recently carried out enabled us to describe 14
species of Termitomyces from Cameroon among which 4
new and 5 new forms of Termitomyces striatus (3) and
Termitomyces subclypeatus sp. nov. (2). The new species
and forms described are Termitomyces grisumbo, T.
mboudaeïna, T. subumkowaani, T. subclypeatus forma
bisporus, T. subclypeatus forma tetrasporus, T. striatus
forma grisumbo, T. striatus forma subperforiata and T.
striatus forma tricystidiata. Also as shown in this colour
poster with species described mostly in their natural
habitat, the description of 5 other species (Termitomyces
mammiformis Heim, T. aurantiacus Heim, T. striatus
forma annulatus (Beeli) Heim, T. schimperi (Pat.) Heim, T.
letestui (Pat.) Heim and T. microcarpus (Berk. & Br.)
Heim previously described by Heim in 1952 is revised and
completed.
734 - Lichenicolous lichens: Independent lines of
evolution? - evidence from Acarospora stafiana
T.H. Nash III 1* , D. Persoh 2 , E. Barreno 3 , M.
Wojciechowski 1 & G. Rambold 2
1 Dept. of Plant Biology, Arizona State University, Box
871601, Tempe, AZ 85287-1601, U.S.A. - 2 Lehrstuhl
Pflanzensystematik, Universitaet Bayreuth,
Universitaetsstrasse 30 - NWI, D-95440 Bayreuth,
Germany. - 3 Plant Biology, Botany, Universitat de
Valencia, C/Dr. Moliner 50, E-46100 Burjasot, Valencia,
Spain. - E-mail: tom.nash@asu.edu
Several common lichenized fungal genera, such as
Acarospora, Buellia, Caloplaca, Lecidea and Rhizocarpon,
comprise lichenicolous as well as free-living species. An
implicit assumption of recognizing lichenicolous species is
that they represent independent lines of evolution.
Molecular approaches offer a powerful tool for testing the
phylogenetic relationships among lichenicolous and
independent taxa. This is a preliminary investigation of
Acarospora, and focuses on A. stafiana, a relatively
common lichenicolous species on Caloplaca trachyphylla
in western North America. We analysed nrDNA ITS
sequences of A. stafiana, its host, other free-living
Acarosporae, other Acarospora hosts, a lichenicolous
fungus (Stigmidium epixanthum) occurring on A. stapfiana,
and a Candelariella sp. that appears at least facultatively
lichenicolous on the same Caloplaca. The results support
the inference that A. stapfiana is an obligate, lichenicolous
species, in so far as the adjacent, free-living Acarosporae
were distinct from the lichenicolous one. But one
surprising result was that the ITS sequence of A. stafiana
was identical with a free-living specimen of Acarospora
hilaris collected from Spain. If this finding is supported by
additional investigations, then the assumption of
independent evolution of the lichenicolous growth-form for
this species is not supported and it may be that Acarospora
stapfiana and A. hilaris should be considered conspecific.
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Book of Abstracts
735 - Phylogenetic studies in the asexual lichen genus
Lepraria
M.P. Nelsen * & A. Gargas
University of Wisconsin - Madison, Department of Botany,
430 Lincoln Drive, Madison, WI 53706-1381, U.S.A. - Email:
mpnelsen@students.wisc.edu
Lepraria, a genus of lichenized fungi, is known to
reproduce solely by asexual propagules. Widespread in
distribution, members of Lepraria are often found growing
on moist, shaded rocks and trees, frequently among
mosses. Morphologically, Lepraria appears quite simple
and bears little similarity to other genera, thus preventing
its classification at a rank higher than genus. We
investigate the phylogenetic position of selected Lepraria
species in relation to other lichenized fungi using rDNA
SSU and ITS sequence data. We also present preliminary
data testing the hypothesis that in the absence of sexual
reproduction, co-cladogenesis between symbionts occurs
using rDNA ITS sequence data from both fungi and algae.
Future studies will include testing for cryptic
recombination within the species L. lobificans.
736 - Molecular studies of the Hyphoderma setigerum
complex
R.H. Nilsson 1* , N. Hallenberg 1 , B. Nordén 1 & N.
Maekawa 2
1 Göteborg University, Botanical Institute, Box 461 ; 405 30
Göteborg, Sweden. - 2 Tottori Mycological Institute, 211
Kokoge ; Tottori ; 689-1125, Japan. - E-mail:
henrik.nilsson@systbot.gu.se
Hyphoderma setigerum (Basidiomycotina,
Homobasidiomycetes) is a corticioid fungus associated
with white rot and is primarily found on dead wood of
deciduous trees. Morphological variation and intersterility
tests within the taxonomical unit formerly known as H.
setigerum have lead to the recognition of a species
complex. The present study uses DNA sequence
information from the ITS region of 50 specimens from
Europe, N America, and Asia to address this variation in a
phylogenetic context. A considerable amount of variation
was found in the DNA sequences; based on DNA sequence
analysis and interfertility tests, several hitherto undescribed
species are shown to exist inside the species complex. The
relation of H. setigerum to H. subsetigerum and H.
nudicephalum is discussed.