Hollardosteus

Hollardosteus Temporal range: Eifelian

reconstruction as a dunkleosteid
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Placodermi
Order:	Arthrodira
Suborder:	Brachythoraci
Family:	incertae sedis
Genus:	Hollardosteus
Species:	H. marocanus
Binomial name
*Hollardosteus marocanus* Lehman, 1976

Hollardosteus marocanus is a brachythoracid arthrodire placoderm from the Middle Devonian of Morocco. Its scrappy remains were found in Eifelian-aged strata from the Tafilat-Maider Valley.^[1]

The inferognathal plate has a well-developed anterior tooth (prong), very similar in form to the inferognathals of the dunkleosteids. However, the dermal surface of the armor is decorated with a pattern of large, crowded tubercules totally unlike the smooth dermal surfaces of dunkleosteid armors. This mix of peculiar features leaves H. marocanus placed as "Arthrodira incertae sedis,"^[1] at least until more complete specimens are found.

References

^ ^a ^b Long, John (editor) (1993). Palaeozoic Vertebrate Biostratigraphy and Biogeography. Baltimore: The Johns Hopkins University Press. p. 148. ISBN 0-8018-4779-6. {{cite book}}: |author= has generic name (help)

"Placodermi"

Kingdom: Animalia
Phylum: Chordata
Subphylum: Vertebrata
Infraphylum: Gnathostomata

Gnathostomata

see Gnathostomata
Placodermi	see below↓

Placodermi

Acanthothoraci *

Hagiangella
Palaeacanthaspidae*	Arabosteus Dobrowlania Kimaspis Kolymaspis Kosoraspis Palaeacanthaspis Radotina Romundina Sudaspis Tlamaspis
Weejasperaspididae	Murrindalaspis Weejasperaspis

Petalichthyida

Diandongpetalichthys Neopetalichthys
Quasipetalichthyidae	Eurycaraspis Pauropetalichthys Quasipetalichthys
Macropetalichthyidae	Ellopetalichthys Epipetalichthys Lunaspis Macropetalichthys Notopetalichthys Shearsbyaspis Tongdzuylepis Wijdeaspis