The annelids (/ ˈænəlɪdz /), also known as the segmented worms, are animals that comprise the phylum Annelida (/ əˈnɛlɪdə /; from Latin anellus 'little ring'). [3][a] The phylum contains over 22,000 extant species, including ragworms, earthworms, and leeches.

2025年3月5日 · annelid, any member of a phylum of invertebrate animals that are characterized by the possession of a body cavity (or coelom), movable bristles (or setae), and a body divided into segments by transverse rings, or annulations, from which they take their name.

Phylum Annelida is a very broad phylum belonging to the kingdom Animalia. The Annelids are found in aquatic as well as terrestrial environments. These are bilaterally symmetrical invertebrate organisms. Their segmented body distinguishes them from any other organism.

2023年8月3日 · Classification of Phylum Annelida. About 8,700 known species of Annelida are divided into four main classes, primarily on the basis of presence and absence of parapodia, setae, metameres, and other morphological features.

环节动物门Annelida为两侧对称、分节的裂生体腔动物。已描述的约17000种，常见种有蚯蚓、蚂蟥 、沙蚕等。体长从几毫米到3米。栖息于海洋、淡水或潮湿的土壤，是软底质生境中最占优势的潜居动物。少数营内寄生生活（花索沙蚕科Arabellidae）。

2024年10月2日 · Phylum Annelida is a diverse group of organisms within the animal kingdom. They are commonly known as segmented worms or annelids, and they exhibit a wide range of adaptations and lifestyles. Annelids can be found in various environments, including aquatic habitats such as marine and freshwater ecosystems, as well as terrestrial habitats with ...

The phylum Annelida is made up of segmented worms such as earthworms. Segmented worms are divided into many repeating segments. There are roughly 15,000 species of annelids. Most belong to one of three classes. A species in each class is pictured in Figure below. Classes of Annelids. The majority of annelids are polychaetes.

2024年12月27日 · Phylum Annelida (L., annelus = little ring or F., anneler = to arrange in rings) is a group of bilaterally symmetrical, coelomate, and segmented animals known commonly as segmented worms. Members of this phylum exhibit a body divided into repeated segments called metameres, which give them structural and functional division.

2020年1月1日 · An updated taxonomic review of freshwater Annelida found in the Neotropical and Antarctic Regions is presented in this chapter. This chapter provides dichotomous identification keys to Polychaeta, Clitellata, and Aphanoneura.

2015年9月1日 · Annelids are a taxon of protostomes comprising more than 1–7,0–00 worldwide–013;distributed species, which can be found in marine, limnic, and terrestrial habitats (Zhang 2–011).