Hindeodus
Hindeodus is an extinct genus of conodonts in the family Anchignathodontidae. The generic name Hindeodus is a tribute to George Jennings Hinde, a British geologist and paleontologist from the 1800s and early 1900s. The suffix -odus typically describe's the animal's teeth, essentially making Hindeodus mean Hinde-teeth.
Conodonts such as Hindeodus are typically small, elongate, marine animals that look similar to eels today. Hindeodus existed from the early Carboniferous through the early Triassic during which they inhabited a wide variety of different environments in the Paleozoic and Triassic seas.[7] Their body consisted entirely of soft tissues, except for an assortment of phosphatic elements believed to be their feeding apparatus.[8] Despite years of controversy regarding their phylogenetic position, conodonts such as Hindeodus are now considered to be vertebrates. They are slightly more derived than the early vertebrates called Cyclostomata, and are part of a large clade of "complex conodonts" called Prioniodontida in the order Ozarkodinina.[7] Hindeodus fossils are distributed worldwide due to the diversity of environments they inhabited.[9] Species of Hindeodus are differentiated by slight variation of the elements of their feeding apparatus. A species of Hindeodus called Hindeodus parvus is particularly well studied because it is used as an index fossil defining the Permian-Triassic boundary.[10]
Hindeodus was first described by Rexroad and Furnish in 1964 during the Illinois State Geological Survey's study of Mississippian stratigraphy.[11] The specimen was found in the Pella Formation of South-central Iowa which is known for excellent preservation of conodonts. However, species of Hindeodus were among the least abundant fossils (less than 0.25 specimens per kilogram of sample).[11] They initially believed that Hindeodus may be a species of Trichondella or Elsonella but determined that Hindeodus is not morphologically and phylogenetically comparable to either and thus, must be a new genus.[11]
While faunal diversity during the end Permian extinction event (251 million years ago) drastically plummeted, Hindeodus survived into the early Triassic.[10] A possible explanation for this is the versatility of certain Hindeodus species in terms of the environments they are able to survive in.[10] Additionally, there is evidence that Hindeodus was able to migrate during the Permian-Triassic transitional period which lead to its wide distribution worldwide during this time.[10]
Hindeodus was primarily soft-bodied; the only mineralized tissue of Hindeodus (and all other conodonts) are their “elements” that are tooth like structures arranged in particular positions and are thought to have served as a feeding apparatus functioning to grasp and intake prey.[7]
