Search results
Results from the WOW.Com Content Network
Fishes are a paraphyletic group and for this reason, the class Pisces seen in older reference works is no longer used in formal taxonomy.Traditional classification divides fish into three extant classes (Agnatha, Chondrichthyes, and Osteichthyes), and with extinct forms sometimes classified within those groups, sometimes as their own classes: [1]
Class Cephalaspidomorphi - lampreys; Superclass Gnathostomata Vertebrates with jaws Class Chondrichthyes (cartilagineous fish - sharks and rays) Class Osteichthyes (bony fish), which has two subclasses: Actinopterygii (ray-finned fish) Sarcopterygii (lobe-finned fish) Full details of higher order fish taxonomy can be found in the Chordata article.
A fish (pl.: fish or fishes) is an aquatic, anamniotic, gill-bearing vertebrate animal with swimming fins and a hard skull, but lacking limbs with digits.Fish can be grouped into the more basal jawless fish and the more common jawed fish, the latter including all living cartilaginous and bony fish, as well as the extinct placoderms and acanthodians.
Fishes of the World is a standard reference for the systematics of fishes.It was first written in 1976 by the American ichthyologist Joseph S. Nelson (1937–2011). Now in its fifth edition (2016), the work is a comprehensive overview of the diversity and classification of the 30,000-plus fish species known to science.
Catalog of Fishes is a comprehensive on-line database and reference work on the scientific names of fish species and genera. It is global in its scope and is hosted by the California Academy of Sciences. It has been compiled and is continuously updated by the curator emeritus of the CAS fish collection, William N. Eschmeyer.
Ichthyology is the branch of zoology devoted to the study of fish, including bony fish (Osteichthyes), cartilaginous fish (Chondrichthyes), and jawless fish ().According to FishBase, 33,400 species of fish had been described as of October 2016, with approximately 250 new species described each year.
Agnatha (/ ˈ æ ɡ n ə θ ə, æ ɡ ˈ n eɪ θ ə /; [3] from Ancient Greek ἀ-(a-) 'without' and γνάθος (gnáthos) 'jaws') is a paraphyletic infraphylum [4] of non-gnathostome vertebrates, or jawless fish, in the phylum Chordata, subphylum Vertebrata, consisting of both living (cyclostomes) and extinct (conodonts, anaspids, and ...
"The science of classification as applied to living organisms, including the study of means of formation of species, etc." [5] "The analysis of an organism's characteristics for the purpose of classification" [6] "Systematics studies phylogeny to provide a pattern that can be translated into the classification and names of the more inclusive ...