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There are 107 classes of animals in 33 phyla in this list. However, different sources give different numbers of classes and phyla. For example, Protura, Diplura, and Collembola are often considered to be the three orders in the class Entognatha. This list should by no means be considered complete and authoritative and should be used carefully.
Category: Animal phyla. 25 languages. ... Bilaterian phyla (1 C, 5 P) Pages in category "Animal phyla" The following 9 pages are in this category, out of 9 total.
The term phylum was coined in 1866 by Ernst Haeckel from the Greek phylon (φῦλον, "race, stock"), related to phyle (φυλή, "tribe, clan"). [4] [5] Haeckel noted that species constantly evolved into new species that seemed to retain few consistent features among themselves and therefore few features that distinguished them as a group ("a self-contained unity"): "perhaps such a real and ...
Lophotrochozoa (/ l ə ˌ f ɒ t r oʊ k oʊ ˈ z oʊ ə /, "crest/wheel animals") is a clade of protostome animals within the Spiralia. The taxon was established as a monophyletic group based on molecular evidence. [2] [3] The clade includes animals like annelids, molluscs, bryozoans, and brachiopods. [4]
Comparison of the head region of Gnathifera. The most distinctive characteristic of gnathiferans is the presence of complex sclerotized mouthparts made of chitin. [2] In most gnathiferans, the anus opens on the dorsal surface of the animal. [6] [7] [8] In micrognathozoans and gnathostomulids, the anus is transient and only forms during defecation.
Scalidophora is a group of marine pseudocoelomate ecdysozoans that was proposed on morphological grounds to unite three phyla: the Kinorhyncha, the Priapulida and the Loricifera. [ 2 ] [ 3 ] The three phyla have four characters in common — chitinous cuticle that is moulted, rings of scalids on the introvert, flosculi, and two rings of ...
Ecdysozoa (/ ˌ ɛ k d ɪ s oʊ ˈ z oʊ ə /) is a group of protostome animals, [9] including Arthropoda (insects, chelicerates (including arachnids), crustaceans, and myriapods), Nematoda, and several smaller phyla. The grouping of these animal phyla into a single clade was first proposed by Eernisse et al. (1992) based on a phylogenetic ...
The calcareous sponges [2] [3] (class Calcarea) are members of the animal phylum Porifera, the cellular sponges. They are characterized by spicules made of calcium carbonate, in the form of high-magnesium calcite or aragonite. While the spicules in most species are triradiate (with three points in a single plane), some species may possess two ...