- Internal[edit]. Below is a consensus evolutionary tree of Chaetognatha, based on both morphological and molecular data, as of 2021.[3].
- The phylum Chaetognatha, also known as arrow worms, contains nearly 200 species of mostly planktonic, bilaterally symmetrical, coelomate, worm-like organisms.
- A systematic compilation of valid Chaetognatha species diversity and distribution collated from published literature has been undertaken in this chapter.
- Chaetognatha characteristics. Worm-like and bilaterally symmetrical. A straight gut and a non-terminal, ventral anus.
- Chaetognatha Species Count: According to the online database The Catalogue of Life there are 132 recognized species of Arrow Worms.
- History of Phylum Chaetognatha: 1. Slabber, in the year 1769, was the first worker to record Sagitta and he placed it in the order Intestina under phylum Vermis.
- Philo Chaetognatha - Importance. Given its ecological importance, theChaetognatha phylumit is surprisingly little known.
- Chaetognatha. In: GBIF Backbone Taxonomy. 291,349 occurrences. ... Chaetognatha Felder, 1874. Common names. Pilorme in Danish.
- Invertebrates in the Plankton: Chaetognatha. Chaetognaths are a dominant part of the plankton, outnumbered only by copepods.
