turbellarian
Quick Summary
Turbellarians are a class of soft-bodied, flattened invertebrates belonging to the phylum Platyhelminthes, commonly known as flatworms. Most turbellarians are free-living, primarily found in aquatic environments, though some inhabit moist terrestrial areas. Unlike many other flatworms, they are not parasitic.12
Key characteristics of turbellarians include bilateral symmetry and the absence of specialized respiratory, skeletal, or circulatory systems. They possess three embryonic layers and a distinct head region containing concentrated sense organs and nervous tissue. While generally hermaphroditic, they are considered primitive compared to other invertebrates. The name "turbellarian" is derived from the Latin word for "bustle" or "stir," referring to the tiny eddies created by their cilia.12
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- flatworm
(flukes), Cestoda (tapeworms), Turbellaria (planarians), and Monogenea. It should be noted that some authorities consider Monogenea, which contains the order Aspidogastrea, to be a subclass within the class Trematoda. Members of all classes except Turbellaria are parasitic during all or part of the life cycle. Most turbellarians are…
Read More(flukes), Cestoda (tapeworms), Turbellaria (planarians), and Monogenea. It should be noted that some authorities consider Monogenea, which contains the order Aspidogastrea, to be a subclass within the class Trematoda. Members of all classes except Turbellaria are parasitic during all or part of the life cycle. Most turbellarians are…
Read More - flatwormAnnotated classification
Class Turbellaria Epidermis usually ciliated at least in part, provided with rhabdoids (minute rodlike structures); body unsegmented; gut present except in order Acoela; life cycle simple; mostly free-living, some ectocommensal, endocommensal (i.e., living, respectively, outside or inside another organism without harming it), or parasitic; about 3,000…
Read MoreClass Turbellaria Epidermis usually ciliated at least in part, provided with rhabdoids (minute rodlike structures); body unsegmented; gut present except in order Acoela; life cycle simple; mostly free-living, some ectocommensal, endocommensal (i.e., living, respectively, outside or inside another organism without harming it), or parasitic; about 3,000…
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