| SYSTEMATIC BIOLOGY |
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| SUPERCLASS CONODONTOMORPHI+ |
Conodontomorphi (KON-o-don-to-MOPF-e) is formed from three Greek roots meaning "cone-toothed forms" [cone- konos (κώνος); tooth- donti (δόντι); form- morfi (μορφή)]. The name is derived from denticles that are very abundant in Paleozoic strata.
The conodonts were very similar to lampreys in overall body form. They had two large eyes and in-line fins only. Their jawless mouths had batteries of teeth that seemed to serve the functions of grasping and then chopping prey. Only in a few sites have the carbonized bodies of conodonts been found; so, the taxonomic system of the animals rests entirely on the structure of the teeth. Their biology is a little difficult to infer from the scant evidence that we have today. They were free-swimming and likely were predators (or at least scavengers) much like the hagfishes. Their particular position in the Craniata is still in doubt. Donoghue et al. (2000) placed them in the Subphylum Conodontophorida as distinct from the Vertebrata (craniata) and sisters to the Myxiniodea.
| HIERARCHICAL TAXONOMY OF THE SUPERCLASS CONODONTOMORPHI. The following descriptions come from Benton (2005) and Nelson (2006). The structure of the following system is based on Sweet and Donoghue (2001). Taxa in red are extinct. |
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SUPERCLASS CONODONTOMORPHI+ CLASS CONODONTA Conodont teeth are common from the late Cambrian to the Late Triassic. Though common, indeed so common that they were used as stratographic standards, the nature of the conodont organism was in doubt until 1983 (Briggs et al. 1983) when lamprey-like animals with conodont teeth were found as nearly complete and highly detailed carbonized films in Scotland. They seem to have had paired eyes. Their dental elements came in 3 forms called S, M, and P. S and M elements were associated with the front end of the mouth and served to grasp prey. P elements were at the back of the pharynx and served to chop the prey to pieces. Although many genera are recognized, they are based on tooth morphology; so, relationships between the taxa are artificial. Late Cambrian to late Triassic UNASSIGNED GENERA Acodus, Amorphognathus, Anticostiodus, Basselodus, Belodina, Carniodus, Cornuodus, Culumbodina, Curtognathus, Dapsilodus, Decoriconus, Diaphorodus, Drepanodus, Erismodus, Erraticodon, Fahraeusodus, Gamachignathus, Hamarodus, Histiodella, Istorinus, Juanognathus, Jumudontus, Kallidontus, Lenodus, Microzarkodina, Oepikodus, Oistodus, Oulodus, Paroistodus, Pedavis, Phragmodus, Polonodus, Pseudobelodina, Pseudooneotodus, Pteracontiodus, Pterospathodus, Pygodus, Scabbardella, Scolopodus, Scyphoidus, Spinodus, Staufferella, Stereoconus, Strachanognathus, Streptognathus, Taoqupognathus, Tripodus, Walliserodus, Yaoxianognathus. ? Semiaccontiodus, Clavohamulus, Drepanoistidus, Utahconus, Hirsutodontus, Clydagnathus UNASSIGNED FAMILY FAMILY PARACORDYLODONTIDAE Paracordylodus. SUBCLASS CAVIDONTI ORDER PROCONODONTIDA UNASSIGNED GENERA Proconodontus FAMILY FRYXELLODONTIDAE Dzikodus, Kallidontus. FAMILY PYGODONTIDAE FAMILY CORDYLODONTIDAE Cordylodus, Econodontus, Iapetognathus. FAMILY ASELLIIDAE FAMILY DAPSILODONTIDAE FAMILY BELODELLIDAE SUBCLASS CONODONTI ORDER PROTOPANDERODONTIDA FAMILY PROTOPANDERODONTIDAE Protopanderodus. FAMILY CLAVOHAMULIDAE FAMILY DREPANOISTODONTIDAE Drepanoistododus FAMILY ACANTHODONTIDAE ORDER PANDERODONTIDA Incertae Sedis: Teridontus FAMILY PANDERODONTIDAE Panderodus. ORDER PRIONIODONTIDA UNASSIGNED GENUS Rossodus FAMILY MULTIOISTODONTIDAE FAMILY OISTODONTIDAE FAMILY PERIODONTIDAE Periodon. FAMILY RHIPIDOGNATHIDAE Trincodus, Appalachignathus, Bergstroemognathus, Rhipidognathus. FAMILY PRIONIODONTIDAE Prioniodus, Reutterodus, Striptognathus. FAMILY BALOGNATHIDAE (?) FAMILY POLYPLACOGNATHIDAE FAMILY DISTOMODONTIDAE Distomodus. FAMILY ICRIODELLIDAE Icriodella. FAMILY ICRIODONTIDAE Icriodus. FAMILY CYRTONIODONTIDAE ORDER PRIONIODINIDA UNASSIGNED GENERA Hibbardella, Idioprionodus, Kladognathus, Phragmodus. FAMILY CHIROGNATIDAE Chirognathus. FAMILY PRIONIODINIDAE Promissum. FAMILY BACTROGNATHIDAE FAMILY ELLISONIIDAE FAMILY GONDOLELLIDAE Gondolella, Neogondolella. FAMILY PLECTODINIDAE (paraphyletic) Aphelognathus, Plectodina, Baltoniodus. ORDER OZARKODINIDA UNASSIGNED GENERA Cordylodus FAMILY SPATHOGNATHODONTIDAE Ancyrodella, Ancyrognathus, Ozarkodina. FAMILY PTEROSPATHODONTIDAE FAMILY KOCKELELLIDAE FAMILY POLYGNATHIDAE Polygnathus. FAMILY PALMATOLEPIDAE Plamatolepis. FAMILY ANCHIGNATHODONTIDAE FAMILY ELECTOGNATHIDAE FAMILY GNATHODONTIDAE FAMILY IDIOGNATHODONTIDAE FAMILY MESOGNATHIDAE FAMILY CAVUSGNATHIDAE FAMILY SWEETOGNATHIDAE |
