Agnatha

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Synonyms for Agnatha

References in periodicals archive ?
Thelodont and other agnathan distributions as tests of lower Palaeozoic continental reconstructions.
Among euryhaline fishes, most teleosts and petromyzontid agnathans (lampreys) are regulators, while chondrichthyans and the myxinoid agnathans (hagfishes) are conformers (see "Water Balance in Elasmobranchs" below).
Novitskaya (2004) reviewed fossil 'agnathans and early fishes' of the former USSR and treated the cyathaspids as an order, Cyathaspidiformes, as Obruchev (1964; order Cyathaspidida) had done previously.
An incorrect name for it is Atla (Patten 1931), since that locality is situated about 5 km to the northwest of Himmiste-Kuigu and has not yielded articulated agnathans or their shields and scales.
Evolution of the brain developmental plan: insights from agnathans. Dev.
The branchial region in vertebrates, including agnathans, is occupied by cephalic neural-crest-derived mesenchymes divided into preotic and postotic cell populations by the otic vesicle.
Lampreys are jawless vertebrates (agnathans) and the most primitive representatives of the cyclostome branch from which it is feasible to obtain embryos routinely.
These strata are rich in fossils, including macro- and microremains of agnathans and fishes, conodonts, diverse shelly fauna and associations of invertebrate microfossils, with intense bioturbation and Skolithos trace fossils (Nestor 1990; Vinn & Wilson 2013; Marss & Nestor 2014), altogether indicating shallowwater environment.
Some marl levels downstream along the Lemovzha River contain well-preserved remains of agnathans and fishes (Ivanov & Lebedev 2011; Skutschas et al.
Because these sheaths are absent in agnathans (Bullock et al., 1984) and invertebrate chordates, myelination most likely developed in the common gnathostome ancestor.
The taxonomy and distribution of agnathans and fishes in southern Britain have been investigated, the regional vertebrate zonal scheme has been updated and characteristic vertebrate assemblages have been correlated with the conodont zonation (Miller & Marss 1999; Turner 2000; Marss & Miller 2004).
Modern-day agnathans (jawless animals, i.e., lamprey and hagfish) have nervous systems that contain large axons surrounded by glial cells, but no myelin.