A team of paleontologists has discovered the first complete skeletal remains of the phoebodus, a 350-million-year-old ancestor of the shark in the Small Atlas region in Morocco.
The discovery was made by Linda Frey, Michael Coates, Michał Ginter, Vachik Hairapetian, Martin Rücklin, Iwan Jerjen and Christian Klug, an international team of paleontologists who published their paper in British Journal, Proceedings of the Royal Society B on October 2nd.
The paper explains that the Phoebodus was known among the paleontological community but only through “isolated teeth and fin spines”. As its skeleton was made soft cartilage rather than hard bone, this is the first time a fossil of its entire body is founded.
The paper continues that the characteristics of the environment of the Small Atlas Mountains, which at the time was a shallow ocean basin, made this discovery possible. The restricted water movement mixed with the low oxygen levels in this area made it possible to preserve the entire structure of the Phoebodus for millions of years.
The scientists proceed to described the creature as having “an anguilliform body, specialized braincase, hyoid arch, elongate jaws and rostrum, complementing its characteristic dentition and ctenacanth fin spines preceding both dorsal fins.”
These characteristics suggest “a likely close relationship” with the Thrinacodus gracia, a shark ancestor that lived in the Carboniferous (a period that that span between 358.9 million years ago and 289.9 million years ago). Both these species are part of the elasmobranch, an ancient and successful lineage that consists of sharks, rays and skates, which has managed to survive four main extinction periods.
The paper adds that the newly found shark ancestor is “the most easily compared [species] with the modern frilled shark Chlamydoselachus” and considers the discovery a great addition to the efforts to understand earliest elasmobranchs.
Ezzoubeir Jabrane is a writer, teacher and entrepreneur. He holds a Master’s Degree in Linguistic and Literary Studies. He has written a number of journalistic, analytical and academic articles in different fields. He’s worked as a teacher of Academic English at Hassan II University in Casablanca and a teacher of English for Engineering in the National Higher School of Arts and Craft (ENSAM), in addition to a number of other private institutions. Ezzoubeir is a founding member of International Morocco and the founder of Exchange Lab, a language center that offers online English courses for individuals, companies and associations.