Martinichthys (no, the genus was not named after martinis) was a genus of blunt-nosed fish known from the Niobraran Sea of Late Cretaceous. Only poorly preserved portions of their skulls, namely their massive rostrums, are known.
The reconstructions are based on their relative, Pentanogmius (Bananogmius) evolutus.
The upper is M. ziphioides, while the bottom is M. brevis.

Wear on their rostrums strongly suggest that they rammed their snouts into shellfish, in order to smash them open, and thus, may have preyed on the giant clam, Volviceramus grandis (which is slightly encrusted with the oyster Pseudoperna congesta), and the rudistid Durania maxima.

V. grandis was, in itself, a living ecosystem (when it was alive, that is). Fossils of V. grandis contained fossils of small fish that lived within it, and the shells, themselves, were thoroughly festooned with the oyster Pseudoperna congesta, which grew on any hard surface available on the bottom of the Niobrara. I only drew a small colony, so as to better show the form of V. grandis.

Durania maxima was a rare inhabitant that suggested that Nebraska was the northern most limit of the rudistid empire.