Maldanomorpha is a

monophyletic In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria: # the grouping contains its own most recent co ...

group, or

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

, of

polychaete Polychaeta () is a paraphyletic class of generally marine Annelid, annelid worms, common name, commonly called bristle worms or polychaetes (). Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called c ...

worms in the phylum

Annelida The annelids (), also known as the segmented worms, are animals that comprise the phylum Annelida (; ). The phylum contains over 22,000 extant species, including ragworms, earthworms, and leeches. The species exist in and have adapted to variou ...

. Several phylogenetic analyses based on morphological and molecular data have shown that this clade unites the families Arenicolidae and Maldanidae. The two main synapomorphies, morphological characters described to unite both families, are a lecithotrophic larval development and the presence of an uncinus, a hook-like structure with barbs.

References

Polychaetes Animals described in 1995 Annelid unranked clades {{Annelid-stub