''Hollardosteus marocanus'' is a

brachythoraci Brachythoraci is an extinct suborder of arthrodire placoderms, armored fish most diverse during the Devonian. Phylogeny Arthrodira is divided into three main groups: the paraphyletic Actinolepida and Phlyctaenii, and then the monophyletic Brac ...

arthrodire Arthrodira (Greek for "jointed neck") is an Order (biology), order of extinct armored, jawed fishes of the class Placodermi that flourished in the Devonian period before their sudden extinction, surviving for about 50 million years and penetratin ...

placoderm Placoderms (from Ancient Greek πλάξ 'plax'', ''plakos'''Plate (animal anatomy), plate' and δέρμα 'derma'''skin') are vertebrate animals of the class (biology), class Placodermi, an extinct group of prehistoric fish known from Pal ...

from the Middle

Devonian The Devonian ( ) is a period (geology), geologic period and system (stratigraphy), system of the Paleozoic era (geology), era during the Phanerozoic eon (geology), eon, spanning 60.3 million years from the end of the preceding Silurian per ...

Morocco Morocco, officially the Kingdom of Morocco, is a country in the Maghreb region of North Africa. It has coastlines on the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria to Algeria–Morocc ...

. Its scrappy remains were found in Eifelian-aged strata from the Tafilat-Maider Valley. 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''," at least until more complete specimens are found.

References

Placoderms of Africa Enigmatic arthrodire taxa Arthrodire genera {{placoderm-stub