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An extinct order of primitive, mastodonlike, herbivorous, hoofed mammals restricted to the Eocene and Oligocene deposits of South America. There is only one family (Pyrotheriidae) in the order and four genera (<i>Pyrotherium</i>, <i>Propyrotherium</i>, <i>Carlozittelia</i>, and <i>Griphodon</i>) in the family.
Industry:Science
An extinct order of quadrupedal eutherian land mammals known from the early Cenozoic deposits of the Rocky Mountain intermontane basins of western North America and, based on a single tooth of <i>Ectoganus gliriformis</i>, from early Cenozoic rocks in South Carolina. The nine known genera of taeniodonts are classified into two families: (1) the medium-size (5–15 kg or 11–33 lb), relatively primitive, omnivorous conoryctids (<i>Schochia, Onychodectes</i>, and <i>Conoryctella</i>, early Paleocene; <i>Huerfanodon</i> and <i>Conoryctes</i>, middle Paleocene); and (2) the larger (15–110 kg or 33–243 lb) and more advanced stylinodontids (<i>Wortmania</i>, early Paleocene; <i>Psittacotherium</i>, middle Paleocene; <i>Ectoganus</i>, late Paleocene to early Eocene; and <i>Stylinodon</i>, middle Eocene).
Industry:Science
An extinct order of regular sea urchins (class Echinoidea) characterized by having a large monocyclic apical disk that forms a ring indented by periproctal plates. Members of the Phymosomatoida have compound ambulacral plating with three or more elements bound together by a single large tubercle. Their jaw apparatus is of the stirodont design, having teeth that are keeled and unfused epiphyses. They comprise two families, one with perforate tubercles and the other with imperforate tubercles, the former being the ancestor to the latter. They first appeared in the Lower Jurassic and became extinct at the end of the Eocene. The morphology of Phymosomatoida suggests that they were epifaunal grazers and lived in shallow shelf seas.
Industry:Science
An extinct order of relatively large placental mammals represented by Paleocene-Eocene fossils from western Europe, North America, and eastern Asia. Pantodonts were an early evolutionary experiment in large-bodied herbivory by primitive placental mammals. They first appeared in Asia during the early Paleocene and disappeared during the middle Eocene, leaving no descendants. With the possible exception of the most primitive pantodonts, all were herbivores, and pantodonts were either the largest or among the largest mammals of their time. The adaptive radiation of pantodonts was diverse and encompassed mammals as different as small (1 kg (2 lb) or less in body mass), arboreal herbivores (Asian <i>Archaeolambda</i>), and large (650 kg (1430 lb)), ground-sloth-like, terrestrial herbivores (North American <i>Barylambda</i>).
Industry:Science
An extinct order of the class Lycopsida (clubmosses) of the Devonian Period. Most of these clubmosses are poorly preserved and not well understood; the notable exception is the widespread <i>Leclercqia complexa</i>, which has been largely reconstructed from fragmentary fossils.
Industry:Science
An extinct order of the class Lycopsida which, together with Isoetales, forms the monophyletic rhizomorphaleans, the most derived and diverse group of clubmosses. The lepidodendraleans are best known as the scale trees that dominate most reconstructions of Upper Carboniferous swamps, where they were the main constituent of many coal-forming peats.
Industry:Science
An extinct order of the class Pinopsida comprising a natural grouping of Paleozoic forest trees or shrubs that first appeared in the Lower Pennsylvanian. They became an important component of the tropical vegetation during the Middle and Upper Pennsylvanian and diminished during the basal Permian. The Cordaitales were divided into three families, Cordaitaceae, Pityaceae, and Poroxylaceae. However, members of the Pityaceae and Poroxylaceae are now known to be either seed ferns or progymnosperms, so only the Cordaitaceae remain. Detailed information about these prominent Paleozoic gymnosperms comes from impression-compression fossils and sandstone casts. However, coal balls, which are mineral nodules in which the plants are preserved with three-dimensional anatomy, have been essential to establishing whole-plant concepts of cordaitean species.
Industry:Science
An extinct Paleozoic group of aquatic arthropods, belonging to the subphylum Chelicerata and class Merostomata and thus related to the living marine xiphosurans (horseshoe crabs) and terrestrial arachnids (spiders, scorpions). Although most eurypterids were less than 10 in. (25 cm) in length, some members of the group were the largest arthropods of all time, reaching sizes up to 6 ft (2 m).
Industry:Science
An extinct paraphyletic order of regular sea urchins (Echinoidea), identified by having a plain, unsculptured test, tubercles that are perforate and crenulate, and no suranal plate intercalated into the apical disc. They almost certainly include ancestors of later groups that developed imperforate and noncrenulate tuberculation and are thus paraphyletic.
Industry:Science
An extinct subclass of stalked Crinoidea; a class of the phylum Echinodermata. The Camerata include more than 235 genera confined to the Paleozoic Era, ranging from the Early Ordovician to the Late Permian. Camerate crinoids were one of the four major subclasses of Paleozoic crinoids. Others include the Cladida, Flexibilia, and Disparida.
Industry:Science
