Search results
Results from the WOW.Com Content Network
The Platyhelminthes have very few synapomorphies - distinguishing features that all Platyhelminthes (but no other animals) exhibit. This makes it difficult to work out their relationships with other groups of animals, as well as the relationships between different groups that are described as members of the Platyhelminthes.
Trematodes are parasitic flatworms of the class Trematoda, specifically parasitic flukes with two suckers: one ventral and the other oral. Trematodes are covered by a tegument, that protects the organism from the environment by providing secretory and absorptive functions. The life cycle of a typical trematode begins with an egg.
It is clear that they evolved from free-living flatworms (turbellarians), but their sister-group was for a long time a matter of debate. The first attempts to reconstruct the phylogeny of flatworms, based on morphological evidence, considered Rhabdocoela to be the sister-group of Neodermata, but this was based on weak morphological similarities ...
Tegument / ˈ t ɛ ɡ j ʊ m ə n t / is a term in helminthology for the outer body covering of members of the phylum Platyhelminthes. The name is derived from a Latin word tegumentum or tegere, meaning "to cover". [1] [2] It is characteristic of flatworms including the broad groups of tapeworms and flukes.
Trematoda is a class of flatworms known as flukes or trematodes.They are obligate internal parasites with a complex life cycle requiring at least two hosts.The intermediate host, in which asexual reproduction occurs, is usually a snail.
Planarians move by beating cilia on the ventral dermis, allowing them to glide along on a film of mucus. Some also can move by undulations of the whole body by the contractions of muscles built into the body membrane. [10] Triclads play an important role in watercourse ecosystems and are often very important as bio-indicators. [11]
The position of the Cestoda within the Platyhelminthes and other Spiralian phyla based on genomic analysis is shown in the phylogenetic tree. The non-parasitic flatworms, traditionally grouped as the "Turbellaria", are paraphyletic, as the parasitic Neodermata including the Cestoda arose within that grouping. The approximate times when major ...
Pseudoceros are simultaneous hermaphrodites [9] and reproduce sexually via random hypodermic insemination through the body tissue. [10] These organisms participate in penis fencing, [9] which is a behavior where the flatworms use their extended penises to stab and inseminate the other, while avoiding becoming inseminated themselves.