Curriculum vitae
1997 - 1998 Studies in Geology at the Ruprecht-Karls-Universität,
Heidelberg
1998 - 2003 Studies in Biology at the Ruprecht-Karls-Universität,Heidelberg
2003 Diploma thesis: "Molecular und morphological characterisation
of the stomodaeum of Platynereis dumerilii (Annelida, Polychaeta)
as a possible head organiser" (at the EMBL Heidelberg, group of
Dr. D. Arendt)
2004 Scientific project: "Endocrine signals and caste determination
in Mastotermes darwiniensis (Hexapoda, Isoptera)" (Dep. of
Animal Physiology/Animal Ecology, Dr.
M. Kaib, Prof.
K. Hoffmann, Univ. Bayreuth)
2005 starting with PhD thesis: "Phylogeny, biogeography and radiation
of gecarcinucoid freshwater crabs (Crustacea, Decapoda, Gecarcinucoidea)",
in a joint project of Dr.
C. Schubart (Univ. Regensburg) and Dr.
D. Brandis (Univ. Heidelberg).
Phylogeny, biogeography and radiation of gecarcinucoid freshwater
crabs
Freshwater crabs can be defined as those brachyuran crustaceans,
that are adapted to the freshwater environment by lecitothrophic
eggs, direct development (without larvae) and brood care. The freshwater
crabs of the world are currently divided into three superfamilies
and one additional family, while their relationship and their closest
marine relatives are still under discussion. Two of the superfamilies,
the Potamoidea and the Gecarcinucoidea are restricted to the Old
World. Especially the taxonomy of the Gecarcinucoidea remained very
unstable and phylogenetic approaches to freshwater crab systematics
did not emerge untill recently.
As the gecarcinucoid crabs show a very disjunct distribution pattern,
several biogeographic hypotheses were proposed to explain their
present distribution. Based on my combined morphological-molecular
phylogenetic approach, I am able to evaluate the probability of
these hypotheses. In consequence, the investigations lead to a new
biogeographic hypothesis that assumes a single transition into freshwater
for the gecarcinucoid ancestors and active dispersal to explain
the present distribution pattern of the Gecarcinucoidea.
My PhD project comprises three main topics:
1. A revision of the earliest fossil freshwater crabs of Europe.
Since the beginning of the 19th century, fossil freshwater crabs
are known from the Miocene Upper Freshwater Molasse deposits of
southern Germany. Later, fossil thelphusoids where also found in
Austria, Hungary, Italy, and Turkey. Although many researchers are
working on recent freshwater crabs, their fossil ancestors gain
little interest. Newly discovered freshwater crab fossils will add
to my revision of the european fossil freshwater crabs, including
detailed descriptions of all fossil species, updated ages for the
type localities and palaeoenvironmental evaluations. As the timepoints
of first occurrence are used to calibrate molecular clocks, this
work is also of interest to molecular phylogenetic studies. In collaboration
with M.
Gross , Landessammlung Joanneum, Graz and S.
Giersch, Staatliches Museum für Naturkunde, Karlsruhe.
2. Morphology of the reproductive apparatus of gecarcinucoid
freshwater crabs
Characters of the male reproductive apparatus, especially of the
first gonopods are widely used in freshwater crab taxonomy. Nevertheless,
the use of these characters was restricted by false assumptions
on their morphology. A detailed and new understanding of the gonopod
function set the focus for large scale phylogenetic studies on the
second gonopod (G2). My histological studies showed that there are
distinct morphological character states of the G2 in the Gecarcinucoidea
that can help to identify monophyletic groups and can be used to
infer a morphological phylogenetic analysis.
The current work concentrates on sperm morphology, the anatomy of
the female spermathecae and the interaction of male and female reproductive
components. The morphological investigations are conduced at the
Institute for Zoology at the University of Heidelberg in the group
of Dr.
D. Brandis.
3. Molecular phylogeny of the Gecarcinucoidea.
With the focus on the Asian gecarcinucoids, I am working on a phylogeny
based on mitochondrial and nuclear markers. This attempt aims not
only on the large scale phylogeny of the Gecarcinucoidea but also
on island radiations in the Indonesian archipelago to shed some
light on the biogeography of SE-Asian gecarcinucoids, applying phylogeographic
methodologies. Moreover, a molecular phylogeny of the Gecarcinucoidea
will help to evaluate the phylogenetic significance of the morphological
character states of the second gonopod. The molecular work is done
in the group of Dr.
C. Schubart
Publications
Gross, M., Klaus, S., 2005. Upper Miocene freshwater crabs from
the north-western margin of the Styrian Basin (Brachyura, Potamoidea).
Ber. Inst. K.-F.-Univ., Graz, 10: 21-23.
Klaus, S, Schubart, C., Brandis, D., 2006. Phylogeny, biogeography
and a new taxonomy for the Gecarcinucoidea Rathbun, 1904 (Decapoda:
Brachyura). Organisms, Diversity & Evolution 6(3): in press.
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