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Noun1.Heterostraci - extinct group of armored jawless fishes or fish-like vertebrate; taxonomy is not clear
animal order - the order of animals
order Ostracodermi, Ostracodermi - extinct group of armored jawless vertebrates; taxonomy is not clear
heterostracan - extinct jawless fish with the anterior part of the body covered with bony plates; of the Silurian and Devonian
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References in periodicals archive ?
Revision of Psammosteus livonicus Obruchev (Agnatha, Heterostraci) from the Devonian Amata Regional Stage of the NW of the East European Platform.
Aufbau des Panzers obersilurische Heterostraci und Osteostraci norddeutschlands (Geschiebe) und Oesels.
Studies on the morphology of the Heterostraci. Journal of Geology, 39, pp.
Because of new information discovered by the fossil turnaround,Elliott believes that this fossil and several similar ones had been inappropriately assigned to an order of fish, Heterostraci, whose members have only a single set of tube-like openings that run to the gills.
New records of psammosteids (Heterostraci) from the Arukula Regional Stage (Middle Devonian) of the Leningrad Region, Russia.
A new psammosteid (Agnatha, Heterostraci) from the Amata Regional Stage of the Main Devonian Field and morpho-histological types of discrete micromeric elements in the family Psammosteidae.
New poraspids (Agnatha, Heterostraci) from the Early Devonian of the western United States.
This is particularly true for the Heterostraci, a widespread group of armoured jawless vertebrates in which the head and forepart of the body are encased in a carapace consisting of a variable number of bony plates, and that are associated with possible non-marine and proximal environments of the Old Red Sandstone continent (see Elliott et al.
Insufficient knowledge has hindered phylogenetic study of the group Heterostraci as a whole, so there has been uncertainty about its relationships with other tessellated heterostracans (e.g.