Stenostomidae is a
family of freshwater
catenulid flatworm
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 ...
s. It is the most species-rich family of catenulids, with about 70 species described, most of them in the
Neotropics.
Catenulids of the family Stenostomidae are characterized by the
brain divided into four clearly separated lobes, two anterior and two posterior, which lie near the mouth. The preoral zone contains a group of sensor cells with
cilia
The cilium, plural cilia (), is a membrane-bound organelle found on most types of eukaryotic cell, and certain microorganisms known as ciliates. Cilia are absent in bacteria and archaea. The cilium has the shape of a slender threadlike projecti ...
ted pits organized in long precerebral series.
References
Catenulida
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