''Tetrastemma'' is a genus of
nemerteans
Nemertea is a phylum of animals also known as ribbon worms or proboscis worms, consisting of 1300 known species. Most ribbon worms are very slim, usually only a few millimeters wide, although a few have relatively short but wide bodies. Many h ...
belonging to the family
Tetrastemmatidae
Tetrastemmatidae is a family of worms belonging to the order Monostilifera
Monostilifera is a suborder of nemertean worms belonging to the class Enopla, a class of worms characterized by the presence of a peculiar armature of spines or plates i ...
.
The genus has
cosmopolitan distribution
In biogeography, cosmopolitan distribution is the term for the range of a taxon that extends across all or most of the world in appropriate habitats. Such a taxon, usually a species, is said to exhibit cosmopolitanism or cosmopolitism. The ext ...
.
Species
Species:
*''
Tetrastemma aberrans''
*''
Tetrastemma albolineatum''
*''
Tetrastemma albomaculatum''
References
Tetrastemmatidae
Nemertea genera
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