Definitions for agnatha
ag·natha

Princeton's WordNetRate this definition:0.0 / 0 votes

1. Agnatha, superclass Agnathanoun

   superclass of eel-shaped chordates lacking jaws and pelvic fins: lampreys; hagfishes; some extinct forms

WiktionaryRate this definition:0.0 / 0 votes

1. agnathanoun

   An agnathan.

2. Etymology: From Agnatha, from ἀ- + γνάθος.

WikipediaRate this definition:0.0 / 0 votes

1. Agnatha

   Agnatha (, Ancient Greek ἀ-γνάθος 'without jaws') is an infraphylum of jawless fish in the phylum Chordata, subphylum Vertebrata, consisting of both present (cyclostomes) and extinct (conodonts and ostracoderms) species. Among recent animals, cyclostomes are sister to all vertebrates with jaws, known as gnathostomes.Recent molecular data, both from rRNA and from mtDNA as well as embryological data, strongly supports the hypothesis that living agnathans, the cyclostomes, are monophyletic.The oldest fossil agnathans appeared in the Cambrian, and two groups still survive today: the lampreys and the hagfish, comprising about 120 species in total. Hagfish are considered members of the subphylum Vertebrata, because they secondarily lost vertebrae; before this event was inferred from molecular and developmental data, the group Craniata was created by Linnaeus (and is still sometimes used as a strictly morphological descriptor) to reference hagfish plus vertebrates. While a few scientists still regard the living agnathans as only superficially similar, and argue that many of these similarities are probably shared basal characteristics of ancient vertebrates, recent taxonomic studies clearly place hagfish (the Myxini or Hyperotreti) with the lampreys (Hyperoartii) as being more closely related to each other than either is to the jawed fishes.

ChatGPTRate this definition:0.0 / 0 votes

1. agnatha

   Agnatha is a superclass of jawless fish in the phylum Chordata. These organisms are characterized by the absence of jaws, paired fins, and scales. The most known types of Agnatha include lampreys and hagfish.

WikidataRate this definition:0.0 / 0 votes

1. Agnatha

   Agnatha is a superclass of jawless fish in the phylum Chordata, subphylum Vertebrata. The group excludes all vertebrates with jaws, known as gnathostomes. The agnathans as a whole are paraphyletic, because most extinct agnathans belong to the stem group of gnathostomes. Recent molecular data, both from rRNA and from mtDNA strongly supports the theory that living agnathans, known as cyclostomes, are monophyletic. The oldest fossil agnathans appeared in the Cambrian, and two groups still survive today: the lampreys and the hagfish, comprising about 120 species in total. Hagfish are considered members of the subphylum Vertebrata, because they secondarily lost vertebrae; before this event was inferred from molecular and developmental data, the group Craniata was created by Linnaeus to reference hagfish plus vertebrates. In addition to the absence of jaws, modern agnathans are characterised by absence of paired fins; the presence of a notochord both in larvae and adults; and seven or more paired gill pouches. Lampreys have a light sensitive pineal eye. All living and most extinct Agnatha do not have an identifiable stomach or any appendages. Fertilization and development are both external. There is no parental care in the Agnatha class. The Agnatha are ectothermic or cold blooded, with a cartilaginous skeleton, and the heart contains 2 chambers.

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1. • Class

How to pronounce agnatha?

1. Alex

   US English

   David

   US English

   Mark

   US English

   Daniel

   British

   Libby

   British

   Mia

   British

   Karen

   Australian

   Hayley

   Australian

   Natasha

   Australian

   Veena

   Indian

   Priya

   Indian

   Neerja

   Indian

   Zira

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   Oliver

   British

   Wendy

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   Fred

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   Tessa

   South African

How to say agnatha in sign language?

Numerology

1. Chaldean Numerology

   The numerical value of agnatha in Chaldean Numerology is: 2

2. Pythagorean Numerology

   The numerical value of agnatha in Pythagorean Numerology is: 7

References

1. ^ Princeton's WordNet
   http://wordnetweb.princeton.edu/perl/webwn?s=agnatha
2. ^ Wiktionary
   https://en.wiktionary.org/wiki/Agnatha
3. ^ Wikipedia
   https://en.wikipedia.org/wiki/Agnatha
4. ^ ChatGPT
   https://chat.openai.com
5. ^ Wikidata
   https://www.wikidata.org/w/index.php?search=agnatha