''Bothrioplana'' is a genus of freshwater

flatworms The flatworms, flat worms, Platyhelminthes, or platyhelminths (from the Greek πλατύ, ''platy'', meaning "flat" and ἕλμινς (root: ἑλμινθ-), ''helminth-'', meaning "worm") are a phylum of relatively simple bilaterian, unsegment ...

, the sole genus in the family Bothrioplanidae and order Bothrioplanida.

Description

Species of ''Bothrioplana'' are small organisms, usually measuring 2–3 mm in length, but reaching up to 7 mm. The body is transparent, elongate, with a round posterior end and a truncate front end, and lacks eyes. The mouth lies on the ventral side at about the middle of the body, as in most

turbellarian The Turbellaria are one of the traditional sub-divisions of the phylum Platyhelminthes (flatworms), and include all the sub-groups that are not exclusively parasitic. There are about 4,500 species, which range from to large freshwater forms more ...

s, and has a short

pharynx The pharynx (plural: pharynges) is the part of the throat behind the mouth and nasal cavity, and above the oesophagus and trachea (the tubes going down to the stomach and the lungs). It is found in vertebrates and invertebrates, though its struc ...

. The intestine is tripartite, similarly to what occurs in triclads, having one anterior and two posterior branches. The posterior branches unite behind the copulatory apparatus and form a single branch. The reproductive system has a pair of testes and a pair of ovaries, as well as a series of vitellaria (yolk-producing glands) that extend along the entire body. Many specimens have the male reproductive system highly reduced or even absent. As a result,

parthenogenesis Parthenogenesis (; from the Greek grc, παρθένος, translit=parthénos, lit=virgin, label=none + grc, γένεσις, translit=génesis, lit=creation, label=none) is a natural form of asexual reproduction in which growth and development ...

may occur.

Ecology

Individuals of ''Bothrioplana'' are usually found in stagnant water, including lakes, pools, wells, and temporary ponds, but may also occur among the moss growing on stones of rivers and brooks. They feed on other small invertebrates, such as ''

Daphnia ''Daphnia'' is a genus of small planktonic crustaceans, in length. ''Daphnia'' are members of the order Anomopoda, and are one of the several small aquatic crustaceans commonly called water fleas because their saltatory swimming style resembl ...

''.

Classification

''Bothrioplana'' was at first classified as a genus in the order Proseriata, but molecular studies have revealed that it is actually the sister-group of

Neodermata Neodermata is a clade of rhabditophoran flatworms containing the parasitic groups Trematoda, Monogenea and Cestoda. Description All neodermatans are parasites, in many groups having a free-swimming larval stage. The most striking feature unit ...

, the parasitic flatworms.

References

{{Taxonbar, from=Q18520385 Rhabditophora