| Keratella quadrata, focus plane on the ventral plate of the lorica (4). |
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| Keratella quadrata, another specimen with only one spine from (2). |
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| Keratella quadrata, lateral view of specimen with resting egg (see below). Alos visible are some euglenid flagellates as commensals/ parasites. (2). |
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| Keratella quadrata, resting eggs |
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| Keratella quadrata,frontal view of a whirling specimen.. |
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| Keratella quadrata, male and female |
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| Keratella quadrata; the arrowheads point to epibiontic peritrich ciliates which are attached to the amictic egg. |
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| Keratella quadrata; focal plane on the dorsal side. The lateral antenna (LT) are clearly visible. They are connected with the brain by nerve cells. Another pair of fibres (F) might be retractor muscles. (30.9.2010) |
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| Keratella quadrata; crop of the above image. |
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| Keratella quadrata; uper image: lorica of a specimen macerated with SDS. The arrows point to the openings of the lateral antennas. Lower image: detail. |
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| Keratella quadrata; infestation by zooflagellates which are living as commensals on the lorica. (Sprockhövel-Hasslinghausen, Teich; 27.5.2012). |
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| Keratella quadrata; another specimen carrying an amictic egg which is also infested by zooflagellates. Obviously Keratella species are infested frequently because of their stiff lorica. |
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| Location: Gevelsberg, Grünes Klassenzimmmer, Teich (1); Heilenbecker Talsperre (4) |
| Habitat: Plankton (1; 2; 3; 4) |
| Date: 27.4.04 (1); 4.2005; (2); 4-8 2006 (3); 30.09.2010 (4) |
