Acestrus elongatus

Acestrus elongatus was previously described based on one very incomplete skull in the Natural History Museum, London. Some have suggested that this partial skull might not represent a billfish however recent discoveries of 2-3 more complete specimens agree with the original hypothesis that this is a billfish-type.

Distinguishing Characteristics:

Ornamentation on top of skull starts further forward vs. A.ornatus (1)
Forward-orientated ornamentation less robust than with A.ornatus (2)

Primary Example: Holotype NHMUK PV P 12954 vs A.ornatus Holotype NHMUK PV P 627

Complete example: Fred Clouter Specimen

Micro-CT Scan - Acestrus elongatus - Fred Clouter Specimen

3D scans undertaken by Tom Sermon with permission.

Additional Examples: Dan Hogburn specimen

3D Scan: Dan Hogburn specimen

3D scans undertaken by Tom Sermon with permission.

References

Casier, E. (1966) Fauna ichthyologique du London Clay. British Museum Natural History London, 1966, 1-496
Monsch, K (2005) Revision of the scombroid fishes from the Cenozoic of England
Rayner, Mitchell, Clouter (2009) London Clay Fossils of Kent and Essex