Name Meaning: Scaly
Location Found: England (Sussex Wealden)
Geologic Era: Jurassic to Cretaceous
Estimated Range: Specimens confirmed in Eurasia and Africa, possibility of a worldwide range
Size: Up to 30 cm long
Extinction: 93.5 million years ago
Pictured below are some pieces of the scaly head armor of a Lepidotes fish. They are still partially buried in matrix, but due to their very dark, shiny coloration, are easily visible. There might be other bony remains still buried in the rock, but I have yet to try and dig them out. This fossil was found in the same location as the probably Baryonyx bone, as well as the unidentified limb/jawbone. While these three animals probably never interacted, they did live in roughly the same area at the same time.
Lepidotes was a fairly common fish in its environment, similar to the modern day carp. They have been found in both freshwater and shallow marine sediments, indicating a very adaptable animal. Lepidotes is one of the first and earliest fish to have its upper jaw not attached to the jugal bone (part of the skull). This means that its jaws were more mobile, and capable of forming a tube-like structure when Lepidotes was trying to hunt. This rapid opening of its jaws would have created suction, which could have pulled smaller prey items closer to the mouth.
Lepidotes probably hunted small, shelled animals such as snails, as its teeth were very rounded, and more suited to crushing than piercing. Lepidotes probably would also have fed on smaller fish and insects resting on the surface it the opportunity presented itself, much like modern carp and bass will often do.
Well armored though Lepidotes was, it was no match for some of the larger predators in the area. One in particular that stands out is Baryonyx, an early spinosaurid dinosaur. Lepidotes scales have been found preserved in the stomach area of one Baryonyx specimen. This indicates that Lepidotes was at least the occasional prey of Baryonyx. If, however, Lepidotes was a common fish for the time, and Baryonyx a preferential fish eater, then it may have formed a significant part of the dinosaur’s diet. There were also sharks and marine reptiles that would have lived in the coastal areas Lepidotes also frequented. Lepidotes would have been relatively low on the food chain, but without it, larger predators would not have survived nearly as well.
Full Fossil: By Ghedoghedo – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=11324852
Life Reconstruction: http://spinops.blogspot.com/2012/06/lepidotes-maximus.html