agnathan


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Related to agnathan: Osteichthyes

ag·na·than

 (ăg′nə-thən)
n.
Any of various fishes lacking jaws, including the hagfishes and the lampreys and many extinct groups, such as the ostracoderms.
[a- + Greek gnathos, jaw; see genu- in Indo-European roots + -an.]
ag′na·than adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

agnathan

(æɡˈneɪθən)
n
(Animals) any jawless eel-like aquatic vertebrate of the superclass Agnatha, which includes the lampreys and hagfishes
adj
(Zoology) of, relating to, or belonging to the superclass Agnatha. See also cyclostome
[C19: from New Latin agnatha, from a-1 + Greek gnathos jaw]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.agnathan - eel-shaped vertebrate without jaws or paired appendages including the cyclostomes and some extinct formsagnathan - eel-shaped vertebrate without jaws or paired appendages including the cyclostomes and some extinct forms
jawless fish, jawless vertebrate
aquatic vertebrate - animal living wholly or chiefly in or on water
Agnatha, superclass Agnatha - superclass of eel-shaped chordates lacking jaws and pelvic fins: lampreys; hagfishes; some extinct forms
ostracoderm - extinct fish-like jawless vertebrate having a heavily armored body; of the Paleozoic
heterostracan - extinct jawless fish with the anterior part of the body covered with bony plates; of the Silurian and Devonian
cephalaspid, osteostracan - extinct jawless fish of the Devonian with armored head
anaspid - extinct small freshwater jawless fish usually having a heterocercal tail and an armored head; of the Silurian and Devonian
conodont - small (2 inches long) extinct eellike fish with a finned tail and a notochord and having cone-shaped teeth containing cellular bone; late Cambrian to late Triassic; possible predecessor of the cyclostomes
cyclostome - primitive aquatic vertebrate
lamper eel, lamprey, lamprey eel - primitive eellike freshwater or anadromous cyclostome having round sucking mouth with a rasping tongue
hagfish, slime eels - eellike cyclostome having a tongue with horny teeth in a round mouth surrounded by eight tentacles; feeds on dead or trapped fishes by boring into their bodies
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
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References in periodicals archive ?
Luksevics in the Department of Geology, Faculty of Geography and Earth Sciences, University of Latvia), 1.42.738.2017 and 3.42.1103.2016 (collecting the agnathan and fish remains from the Gauja and Amata deposits of the Baltic Region and comparison of vertebrate assemblages).
The Borschovo section of the Gauja and Amata regional stages (Leningrad Region, Russia): sedimentology and biostratigraphy
The first assemblage of vertebrates to be described from the Eastport Formation of Maine, USA, includes agnathan remains comprising scale fragments of osteostracans and anaspids, and scales of thelodonts.
Microvertebrates from the Silurian-Devonian boundary beds of the Eastport Formation, Maine, eastern USA
The two main taxonomic groups of agnathan or cyclostome fish are Hyperoartia, lampreys and Hyperotreti, and hagfish (for a review of agnathan ion and water homeostasis see Karnaky, 1998; Evans and Claiborne, 2009).
Water transport and functional dynamics of aquaporins in osmoregulatory organs of fishes
Aryl hydrocarbon receptor function in early vertebrates: inducibility of cytochrome P450 1A in agnathan and elasmobranch fish.
Comparative chronic liver toxicity of benzo[a]pyrene in two populations of the Atlantic killifish (Fundulus heteroclitus) with different exposure histories
Agnathan vertebrates in the Lower Silurian of Gotland, Sweden.
Thelodonts (Agnatha) from the basal beds of the Kuressaare Stage, Ludlow, Upper Silurian of Estonia/Telodondid (Agnatha) Kuressaare lademe (Ludlow, Ulem-Silur) basaalsetest kihtidest Eestis
We collected a total of 18,852 nekton individuals: two cephalopud, one agnathan, two elasmobranch, and 57 fish taxa from 163 surface trawls (see Table 1 for scientific names of all species).
Juvenile salmonid distribution, growth, condition, origin, and environmental and species associations in the Northern California Current *
The two structures of primary importance in the transition from agnathan (jawless) fish to gnathostomes were the mandibular arch (gill arch 2) and the hyoid arch (gill arch 3).
Phylogeny and embryology of the facial nerve and related structures. Part I: phylogeny
IMMUNODETECTION OF AN NHE-LIKE PROTEIN IN THE GILLS OF AN AGNATHAN AND AN ELASMOBRANCH, Brian P.
Saturday's Sessions
The Boothiaspidinae, a new agnathan subfamily (Heterostraci, Cyathaspididae) from the Late Silurian and Early Devonian of the western United States and the Canadian Arctic.
A new species of cyathaspid (Vertebrata: Pteraspidomorphi: Heterostraci) from the Lower Devonian Drake Bay Formation, Prince of Wales Island, Nunavut, Arctic Canada
Somatic diversification of variable lymphocyte receptors in the agnathan sea lamprey.
The sea urchin genome as a window on function
Metamorphosis of larval sea lamprey Petromyzon marinus (an agnathan fish) is also affected by exposure to perchlorate (Manzon and Youson 1997, 2002; Manzon et al.
Effects of ammonium perchlorate on thyroid function in developing fathead minnows, pimephales promelas
This agnathan system is in many ways analogous in function to jawed vertebrate Ig systems.
Marine invertebrate genome sequences and our evolving understanding of animal immunity

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