Chondrenchelyida
Chondrenchelyida is an extinct order of chimaeroid fish that lived during the Carboniferous and Permian periods. These cartilaginous fish are known from fossilized remains found in various locations worldwide, particularly in marine sedimentary rocks. Chimaeroids, also known as ghost sharks or ratfish, are cartilaginous fish related to sharks and rays, distinguished by their unique anatomical features.
Fossils attributed to Chondrenchelyida exhibit characteristics typical of chimaeroids, including a single gill opening on each
The taxonomic placement of Chondrenchelyida within the Chondrichthyes (cartilaginous fishes) is well-established, though its precise evolutionary