Leedsichthys
Leeds-ick-fissName meaning: Leeds Fish
Time Period: Oxfordian (Late Jurassic) 165–148 Mya
Locations: England-France-Germany-Chile
Taxonomy: Chordata-Actinopterygii-Pachycormiformes-Pachycormidae
Species: L. problematicus
Characteristics ~ ~ ~ ~
Leedsichthys is the embodiment of the phrase there's always a bigger fish. Size estimates vary due to its problematic nature but most estimates are up to 54 feet long, making Leedichthys is the largest known boney fish ever. Leedsichthys is presumed to be a filter feeder using its mouth it could open widely to swallow loads of shrimp and krill. Leedsichthys had the standard fin configuration of most fish including a anal, tail, pectoral, and a dorsal fin. Leedsichthys at colossal size could only swim at around 11 mph relying on it's sheer size to fend of predators. Leedsichthys likely laid millions of spawn with very little if any ever making it to adulthood. It’s predators were Metriorhynchus and Liopleurodon. which preyed upon weak and young individuals. Leedsichthys is believed to have gone extinct at the end of the Oxfordian due to climate change effecting zooplankton populations.
History & Fossils ~ ~ ~ ~
Fish are not made of the traditional bone of most other vertebrates, with fish being made of cartilage allows them to move more flexibly; however that makes fossilization difficult due to it's light and fragile nature. More Leedsichthys material is known like gill rakers which tell us that it is a filter feeder, some fragmentary skull and Supraneuralia bits (supporting skull plates), Branchiostegal Rays which support the gill membranes and some fragmentary vertabrae which make determining its length difficult. Leedsichthys was discovered in the 1880's by farmer Alfred Nicholson Leeds and speculated by John Hulke that it's fins were stegosaur plates. Othneil Charles Marsh and Arthur Smith Woodward furthur analyzed it and named it Leedsichthys problematica with the species name because of how frustrating fish cartilage is to work with. It was considered to be renamed toLeedsia problematica because Leedsichthys sounded unprofessional but it didn't go through.
