The flatworms, flat worms, Platyhelminthes, or platyhelminths are a phylum of relatively simple bilaterian, unsegmented, soft-bodied invertebrates. Being acoelomates, and having no specialised circulatory and respiratory organs, they are restricted to having flattened shapes that allow oxygen and nutrients to pass through their bodies by diffusion. The digestive cavity has only one opening for both ingestion and egestion ; as a result, the food can not be processed continuously.
Animal sexual behaviour takes many different forms, including within the same species. Common mating or reproductively motivated systems include monogamy, polygyny, polyandry, polygamy and promiscuity. Other sexual behaviour may be reproductively motivated or non-reproductively motivated.
Pseudocerotidae is a family of flatworms which includes the Bedford's flatworm. Pseudocerotidae are simple organisms categorized by their oval bodies and tentacles and bright colors. They use the cilia to glide along surfaces. Most commonly referred to as marine flatworms, closely related to the orders Macrostomorpha and Lecithoepitheliata. These organisms have very complex reproductive systems, no blood systems or organs for gas exchange, a simple brain and are hermaphroditic.
Pseudoceros is a genus of the flatworms Platyhelminthes.
Pseudobiceros hancockanus is a species of hermaphroditic marine flatworm in the family Pseudocerotidae. It is also known as Hancock's flatworm.
Macrostomum is a genus of flatworm with a worldwide distribution, with over a hundred species described to date. These hermaphroditic, free-living flatworms are usually small in size, with large species reaching up to 5 mm in body length. They are usually transparent, and the smaller species appear rather round in cross-section than dorsoventrally flattened.
Pseudobiceros bedfordi is a species of flatworm in the family Pseudocerotidae.
Acanthozoon is a genus of polyclad flatworms belonging to the family Pseudocerotidae.
Notocomplana is a genus of flatworms. It is the only genus in the monotypic family Notocomplanidae.
Pseudobiceros fulgor, also known the lightning worm, is a species of marine flatworm from the family Pseudocerotidae and belongs to the class Turbellaria. These flatworms are commonly found in the tropics of the Indo-Pacific region. They can be found in shallow coral reef environments.
