Branchiopoda
Triops longicaudatus ( Notostraca )
- Kiemenfüßer - Anostraca
- Claws tails - Onychura
- Back Schaler - Notostraca
The Blattfußkrebse or Kiemenfußkrebse ( Branchiopoda ) provide a summary of the Kiemenfüßer ( Anostraca ), the back Schaler ( Notostraca; see, among others, Triops ) and the claws tails ( Onychura ) dar.
The Blattfußkrebse are typical freshwater residents who have originally evolved from marine ancestors. Secondary, some species are returned to the sea. Recent forms have it survives primarily in Relic and extreme habitats (eg, temporary waters, Binnensalzsee ).
Arguments for monophyly of Blattfußkrebse are their amoeba- like sperm, the filter apparatus formed by bristled torso extremities as well as the building of the nauplius larvae.
The extremities of the hull Blattfußkrebse ( Branchiopoda ) are originally zweiästige leaf legs and thus namesake. You have three original features. Breathing take located on the outer leg base gills ( Epipoditen ). Food intake is done first using the filter apparatus, which is formed by the long-bristled leaf legs to the hull. Neighboring leaf legs form successively temporary suction chambers. The resulting water flow drives food particles from the medium to the bristle comb the blade legs. Following further located on the inner leg base bristles guide the filtered food particles in a ventral food groove to the mouth. The movement is done by metachronous kicking and is combined with the described filtering food intake. The legs can be modified secondarily particularly in miniaturized forms.
The nauplius larva of Blattfußkrebse ( Branchiopoda ) has unarticulated I. antennas. There is a hinge zone on the bristles of the Second antennas. The mandibles are einästig. The labrum is extended.
The system of Blattfußkrebse ( branchiopods ) is shown with its basic components in the following.
Back Schaler ( Notostraca )
Spinicaudata
Cyclestheria hislopii
Haplopoda ( = Leptodora kindti )
Laevicaudata
Kiemenfüßer ( Anostraca )
Arguments for a clade consisting of spinal damage Phyllopoda learning ( Notostraca ) tails and claws ( Onychura ), the incorporation of the compound eyes in a pocket of the head capsule ( internalization ) and the 4- becherige Naupliusauge, if the latter is a derived condition.
Arguments for monophyly of the claws tails ( Onychura ) are the secondary körperumhüllende carapace, the reduction in the primary carapace to a head shield claws and nature of the tail fork ( Furka).
In support of a Monophylums " Conchostraca " within the claws tails Onychura consisting of Laevicaudata and Spinicaudata lacking apomorphies. Previously recognized features have proven to be convergent.
Furthermore, the type Cyclestheria hislopii not one of the Spinicaudata, but forms a monophyletic group with the Cladocera. This is suggested as an apomorphy of the year cyclical alternation of parthenogenetic and bisexual generations, which is common to both taxa.
An alternative relationship hypothesis comes from Ax (1999). After that, the higher crustaceans ( Malacostraca ) are within the Blattfußkrebse ( Branchiopoda ), and form with them the monophyly of Phyllopodomorpha. This alternative hypothesis yields the following system:
Higher crustaceans ( Malacostraca )
Claws tails ( Onychura )
Back Schaler ( Notostraca )
Kiemenfüßer ( Anostraca )