Cladocera

1. Cladocera

Abakumov Anton
1-year CORELIS master student
St.Petersburg State University

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What the Cladocerans are?
The Cladocerans are an order of small crustaceans
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4 orders:
1. Cladocera (water flee);
2. Anostraca (fairy shrimps)
3. Notostraca (tadpole
shrimps) ;
4. Conchostraca (clam
shrimps) ;
Size <1mm.
fig.1 – 4 phylogenetic orders and extinct branches
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Time range
Known from mid-Mesozoic era (~170 mln.y.ago);
First modern Cladocera – 150 mln.y.ago. (Jurassic period);
For the last 200 000 years no morphological changes have
been observed.
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fig.2 – meso-cenozoic time scale

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Where to collect samples from?
Paleolimnological samples are
usually being taken from the
basin parts ;
Major lakes
habitats
The
abundance
of
Cladocerance is the highest in
the mid-latitudes at t=15-20C
Open water planctonic habitats
Littoral benthic habitats
Cladocerans eggs store its
genetic material for centures ;
After death Cladocera breaks
into thousands of fragments
(usually several thousand per
cm3).
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The use of Cladocera in tracking environmental change
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Climatic change – (water temperature) ;
Lake level changes and lake terrestrialization ;
Lake eutrophication ;
Acidification (pH level).
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Living subfossils: carapace (left) and claws (right)

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Reconstruction methods
•Cladocerans size as an indicator of water
temperature and fish abundance ;
•Cladocerans subfossils respond to trophic state ;
•Melanin as an indicator of optical lake`s envinroment
An individual cladocera
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Freshwater cladocera

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