Enseosteus

{{Automatic taxobox

| 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=96–98}}

| image = Enseosteus marocanensis.png

| image_caption = Enseosteus marocanensis

| taxon = Enseosteus

| authority = Jaeckel, 1919

| type_species = Enseosteus jaekelli

| type_species_authority = Gross, 1932

| subdivision_ranks = Species

| subdivision = * E. jaekelli Gross, 1932

• E. hermanni Stensiö 1959
• E. marocensis Rücklin, 2011

| synonyms = * Ottonosteus jaekeli Stensiö, 1959

}}

Enseosteus is an extinct genus of small selenosteid arthrodire placoderms known from the Upper Frasnian Kellwasserkalk facies of Late Devonian Germany 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}}

Enseosteus is very similar to the other Kellwasserkalk selenosteids, though, the type species, E. jaekelli, has a bulbous, knob-shaped rostrum. Denison (1978) synonymizes the genera Ottonosteus (O. jaekeli = E. hermanni) and Walterosteus with Enseosteus, claiming that the 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.