Chordates are divided into three subphyla: Vertebrata (fish, amphibians, reptiles, birds, and mammals); Tunicata or Urochordata (sea squirts, salps); and Cephalochordata (which includes lancelets)….Chordata.

Which fish is included in phylum Chordata?

Chordates are divided into three subphyla: Vertebrata (fish, amphibians, reptiles, birds, and mammals); Tunicata or Urochordata (sea squirts, salps); and Cephalochordata (which includes lancelets)….Chordata.

Cyclostomata Myxini (hagfishes) Hyperoartia/Petromyzontida (lampreys)
(Agnathans)

What are the 3 classifications of fish?

Nelson, among others. Fishes are typically divided into three groups: superclass Agnatha (jawless fishes), class Chondrichthyes (cartilaginous fishes), and superclass Osteichthyes (bony fishes). The latter two groups are included within the infraphylum Gnathostomata, a category containing all jawed vertebrates.

What are examples of Cephalaspidomorphi?

lampreys. Petromyzontiformes. rays, sharks, and relatives. Chondrichthyes.

  • Ohio lamprey. Ichthyomyzon bdellium.
  • Lake trout. Salvelinus namaycush. Eel sucker. Petromyzon marinus.
  • Eel sucker. Petromyzon marinus.
  • lampreys. Petromyzontidae.

    • Do Petromyzontida have jaws?

    The discussion below, for convenience, separates the modern “cyclostomes” into the class Myxini and class Petromyzontida. The defining features of the living jawless fishes are the lack of jaws and lack of paired lateral appendages (fins).

    What are the 3 Subphyla in the phylum Chordata?

    The prevailing view holds that the phylum Chordata consists of three subphyla: Urochordata (Tunicata), Cephalochordata and Vertebrata (figure 1a).

    What phylum does fish belong to?

    phylum Chordata
    For example, fish belong to the kingdom Animalia, the phylum Chordata, and from there are grouped more specifically into several classes, orders, families, and thousands of genus and species.

    What are the 7 classification of fish?

    This hierarchical system moves from largest and most general to smallest and most specific: kingdom, phylum, class, order, family, genus, and species.

    What are the 7 classes of fish?

    Taxonomy

    • Class Agnatha (jawless fish) Subclass Cyclostomata (hagfish and lampreys)
    • Class Chondrichthyes (cartilaginous fish) Subclass Elasmobranchii (sharks and rays)
    • Class Placodermi (armoured fish) †
    • Class Acanthodii (“spiny sharks”, sometimes classified under bony fishes)†
    • Class Osteichthyes (bony fish)

    What are two differences between Agnathans and Cephalaspidomorphi?

    The bony fish differ from the Agnatha because they have jaws. The bony fish differ from the Chondrichthyes because the bony fish have skeletons made of bone. Most bony fish have scales, some have armor plating, and others, such as the catfish, lack any kind of covering over the skin and thus are completely naked.

    Do Agnatha lay eggs?

    A female produces a small number of tough-skinned yolk-filled eggs about 2 cm (0.8 inch) long that hatch into miniature adults. Hagfishes locate their food by scent.

    How do Agnatha fish differ from osteichthyes fish?

    Are hagfishes blind?

    Hagfish are almost blind, but have well developed senses of touch and smell. They have four pairs of sensing tentacles arranged around their mouth. The mouth lacks jaws, but a hagfish is equipped with two pairs of tooth-like rasps on the top of a tongue-like projection.

    How are the Agnatha and Gnathostomata different?

    If evidence from fossil and living forms is combined, the Agnatha are distinguishable from the other craniates (Gnathostomata) by what they lack: jaws, lateral fins supported by fin rays, vertebrae, a horizontal semicircular canal in the ear, and genital ducts.

    When did the Agnatha first appear?

    Early Silurian to Late Devonian (444–359 million years ago). Superclass Agnatha is made up of living and extinct forms. In older classifications, extant forms—that is, the lampreys and hagfishes— were grouped together as Cyclostomata (round mouth).

    How are the gills of agnathans different from those of other organisms?

    Unlike the slitlike gills of gnathostomes, the gills of agnathans are pouchlike and open through pores.

    What can agnathans tell us about vertebrate evolution?

    Agnathans (jawless fishes) represent a class of vertebrates whose lineage diverged from the ancestors of jawed vertebrates (gnathostomes) approximately 550 million years ago. Sequence information from extant agnathans (lampreys and hagfishes) thus has the potential to offer valuable insights into vertebrate genome evolution.