Hemichordata (/ ˌ h ɛ m ɪ k ɔːr ˈ d eɪ t ə / HEM-ih-kor-DAY-tə) is a phylum which consists of triploblastic, eucoelomate, and bilaterally symmetrical marine deuterostome animals, generally considered the sister group of the echinoderms.

2023年8月3日 · Hemichordata Definition. Hemichordata (Gr., hemi, half; chorde, cord) means they are ‘half’ of ‘part’ chordates, a fact that is disputed. They are usually vermiform, solitary, or colonial enterocoelous coelomate animals with an intra-epidermal nervous system and a pre-oral with or without gill-slits and without typical nephridia.

2024年3月31日 · Phylum Hemichordata is a small marine phylum of worm-like animals known as Acorn Worms. They are distinct from chordates and serve as important connecting links between vertebrates and invertebrates. Phylum Hemichordata exhibits the following characteristics:

hemichordate, any of a group of wormlike marine invertebrates closely related to both chordates and echinoderms and usually considered to constitute a phylum, the Hemichordata.

2025年2月14日 · Hemichordata is a unique phylum of marine invertebrates found in a wide range of depths and habitats. Two distinctly different body plans exist in this phylum: the large, solitary acorn worms (Class Enteropneusta), and the filter-feeding colonies of the class Pterobranchia.

The Hemichordata is a phylum of worm-shaped marine deuterostome animals. They are probably the sister group of the echinoderms. They date back to the Lower or Middle Cambrian and include an important class of fossils called graptolites, most of which became extinct in …

2017年10月16日 · The main difference between Hemichordata and Chordata is that Hemichordata contains an epidermal nervous system whereas Chordata contains a central nervous system. Chordates contain a dorsal, tubular nerve cord.

2023年11月12日 · Phylum Hemichordata is a group of marine deuterostomes having proboscis, collar, and trunk in the body with pharyngeal gill slits and intra-epidermal nervous system. The animals are exclusively marine. They remain either solitary or form colonies.

2023年1月25日 · Hemichordata is a lesser-known phylum of the animal kingdom. Hemichordates are usually vermiform, solitary, or colonial enterocoelous coelomate animals with an intra-epidermal nervous system and a pre-oral with or without gill-slits and without typical nephridia.

Hemichordates are found throughout the world’s oceans, with the highest reported numbers by regions with marine labs and diligent taxonomic efforts (e.g. North Pacific and North Atlantic). Pterobranchs are abundant in Antarctica, but have also been found at lower latitudes.