Walterosteus

{{Italic title}}

{{Taxobox

| name = Walterosteus

| image = Walterosteus lelievrei.jpg

| image_caption = W. lelievrei

| fossil_range = Late Frasnian{{cite book|last=Denison|first=Robert|title=Handbook of Paleoichthyology, Volume 2, Placodermi|year=1978|publisher=Gustav Fischer Verlage|location=New York|isbn=9780895740274|pages=98}}

| regnum = Animalia

| phylum = Chordata

| classis = Placodermi

| ordo = Arthrodira

| subordo = Brachythoraci

| infraordo = Coccosteina

| superfamilia = Dinichthyloidea

| familia = Selenosteidae

| genus = Walterosteus

| type_species = Walterosteus pachyostoides

| type_species_authority = Stensiö 1959

| subdivision_ranks = Species

| subdivision =

• W. pachyostoides Stensiö 1959
• W. grossi (Maish, 1998)
• W. lelievrei Rücklin 2011

| synonyms =

• Wildungenichthys grossi Maish, 1998

}}

Walterosteus is an extinct genus of small selenosteid arthrodire placoderms known from the Upper Frasnian Kellwasserkalk facies of Late Devonian Germany{{rp|96}} and Morocco.{{cite journal|last=RÜCKLIN|first=MARTIN|title=First selenosteid placoderms from the eastern Anti-Atlas of Morocco; osteology, phylogeny and palaeogeographical implications|journal=Palaeontology|date=January 14, 2011|volume=56|issue=1|pages=25–62|doi=10.1111/j.1475-4983.2010.01026.x}}

Walterosteus is very similar to the other Kellwasserkalk selenosteids. This similarity lead Denison (1978) to synonymize the genus, together with Ottonosteus (O. jaekeli = E. hermanni), into Enseosteus, claiming that the former two genera are too similar to Enseosteus to merit separate genus status. Rücklin (2011) agrees with Denison's synonymizing of Ottonosteus, but rejects Denison's synonymization of Walterosteus, claiming how Walterosteus has a contact between the rostral plate and the pineal plate, which Enseosteus does not.