Aspidorhynchus acutirostris, and it's a huge one!

Aspidorhynchus acutirostris Blainville 1818

    Upper Jurassic

    Tithonian (Malm zeta)

    Solnhofen area

    Schernfeld

    Schöpfel-Bruch

    Germany

    size 90cm /  35.5"

    The systematics of Aspidorhynchidae badly needs review. To my knowledge, there are three genera known: Aspidorhynchus, Belonostomus and Vinctifer – two of these genera occur in the Upper Jurassic of Solnhofen (Aspidorhynchus and Belonostomus). Vinctifer is common in the Santana Formation of Brazil. The interrelationships of these three genera are more or less unknown.

    Although the Aspidorhynchidae would have looked superficially similar to the present day gar or a scaled-down version of a modern swordfish, its closest living relative is actually the bowfin.

    Aspidorhynchus (meaning "shield snout") was a genus of fishes that lived in the Jurassic and Cretaceous period. Aspidorhynchus was a slender, fast swimming fish, with tooth lined, elongated yaws. The upper jaw was longer than the lower jaw, ending in a toothless spike. This is a distinguishing characteristic for Aspidorhynchus and Belonostomus; the upper and lower yaw of Belonostomus having the same length.

    The largest Aspidorhynchus I have ever seen from Solnhofen would have reached a length of over 1,20 m (4 feet!). Unfortunately, the head was missing. Average size is around 60cm (2 feet). Aspidorhynchus is characterized by a ganoid scale covering with much deepened scales along the flank, by an elongate fusiform body and head with long slender snout, and by an externally symmetrical tail. All fins are rather small. Dorsal and anal fins are positioned far back on the body and opposite one another. The pelvic fins are inserted closer to the anal than to the pectorals. The vertebral column shows some ossification with thin ringlike or half centra.

    Their slender body profile and the fact that the upper jaw bones were immobile preventing the fish from inhaling their prey, suggest that Aspidorhynchus was designed to be a predator. Fossil stomach remains of other fish have been found in specimens of Aspidorhynchus. Long and delicate gill rakers indicate that this fish was also able to filter feed to supplement its diet.