Planarians are bilaterian flatworms that lack a fluid-filled body cavity, and the space between their organ systems is filled with parenchyma. [5][13] Planarians lack a circulatory system, and absorb oxygen through their body wall. They uptake food to their gut using a muscular pharynx, and nutrients diffuse to internal tissues.

planarian, (class Turbellaria), any of a group of widely distributed, mostly free-living flatworms of the class Turbellaria (phylum Platyhelminthes). Planaria is the name of one genus, but the name planarian is used to designate any member of the family Planariidae and related families.

Currently the genus Planaria is defined as freshwater triclads with oviducts that unite to form a common oviduct without embracing the bursa copulatrix and with an adenodactyl present in the male atrium. The testes occur along the whole body.

Aug 15, 2024 · Planaria are possibly the weirdest worm that will ever visit your aquarium. Their unusual traits make them widely studied in the scientific community… Perhaps the weirdest thing is when you cut one. Let’s say you cut a planarian into 5 pieces.

Planaria or Planarians (singular: Planarian) are also called “cross-eyed worms”. They are a group of tiny flatworms belonging to the phylum of Platyhelminthes. They are free-living organisms and widely distributed in all kinds of freshwater habits.

Planarians are flatworms capable of dramatic feats of regeneration, which have been studied for over two centuries. Recent findings identify key cellular and molecular principles underlying these feats.

Planaria are organisms with a unique research history, and provide a model for examining complex learning within their simple behavioral repertoire. However, species used in research appear to be selected based on convention, or ease of access.

Planarians are flat, soft-bodied worms with a triploblastic body plan and lacking visible segmentation. Many hundred species are known, including fresh- and seawater dwellers and even terrestrial forms.

Planaria are flatworms in the phylum Platyhelminthes with amazing regeneration abilities giving them the title 'immortal under the edge of a knife'. There are many different species that inhabit freshwater, marine and terrestrial ecosystems.

What is a Planarian? Planaria are free-living flatworms that live in quiet ponds or bodies of water. In some areas you can even catch a few planarian by attaching a piece of liver to a fish hook and a sinker and dropping it into the water.