Dactylobiotus dispar (II) |
A Dactylobiotus dispar tardigrade,
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"Looks like a typical Macrobiotus moss eutardigrade"
you will possibly think after a first glance and you would not be fully wrong. |
Tardigrade Dactylobiotus dispar,
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There are only a few species within the genus Dactylobiotus, as a consequence it might be possible also for us amateurs to come close to a species determination. First we will have a look at the anterior part of the body: |
Tardigrade Dactylobiotus dispar,
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Dactylobiotus dispar has two characteristic bumps (elevations) at its backside, between the third and fourth pair of legs. They are not photographed easily but are conspicuous when looking at a living animal. |
One of the bumps on the backside of the tardigrade Dactylobiotus dispar as seen from aside (arrow). The second bump is hidden behind the first. |
The visual appearance of the eggs of Dactylobiotus dispar is an important taxonomic criterion and helps to distinguish related species like Macrobiotus macronyx and Macrobiotus ambiguus . The eggs are deposited freely, not in the shed cuticula. Their maximum diameter is about 90 µm. |
Egg of the tardigrade Dactylobiotus dispar .
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Furthermore there are the mouth lamellae. According to Walter Maucci Dactylobiotus dispar should have 10 of those lamellae. It might turn out to be difficult to count the lamellae under the light microscope. We suggest to leave this activity to the taxonomic specialists. Please keep in mind that the tardigrades do not like to be quenched or turned between slide and cover glass just in order to count their lamellae. |
Fine lamellae surround the mouth opening
of Dactylobiotus dispar .
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In the next issue we will see that some of the Dactylobiotus dispar females apparently check out their environment in order to find an optimum shelter for the deposition of their eggs. |
Literature
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© Text, images and video clips by
Martin Mach (webmaster@baertierchen.de).
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