Germanonautilus Temporal range: Triassic | |
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Germanonautilus suevicus | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Mollusca |
Class: | Cephalopoda |
Subclass: | Nautiloidea |
Order: | Nautilida |
Family: | † Tainoceratidae |
Genus: | † Germanonautilus Mojsisovics, 1902 |
Germanonautilus is a cephalopod genus included in the nautilid family Tainoceratidae, found widespread in the Triassic of North America, Europe, Asia, and north Africa. The shell is a moderately involute nautilicone (a form based on Nautilus ); whorl section subquadrate to trapezoidal, widest across the umbilical shoulders, flanks flattened and ventrally convergent, venter flat and wide, dorsum narrowly and deeply impressed. The suture is with broad and deep lateral lobes and a shallow ventral lobe. The siphuncle is central and nummuloidal, composed of expanded segments that give a beaded appearance.
Redlichiida is an order of trilobites, a group of extinct marine arthropods. Species assigned to the order Redlichiida are among the first trilobites to appear in the fossil record, about halfway during the Lower Cambrian. Due to the difficulty to relate sediments in different areas, there remains some discussion, but among the earliest are Fallotaspis, and Lemdadella, both belonging to this order. The first representatives of the orders Corynexochida and Ptychopariida also appear very early on and may prove to be even earlier than any redlichiid species. In terms of anatomical comparison, the earliest redlichiid species are probably ancestral to all other trilobite orders and share many primitive characters. The last redlichiid trilobites died out before the end of the Middle Cambrian.
The occipital lobe is one of the four major lobes of the cerebral cortex in the brain of mammals. The name derives from its position at the back of the head, from the Latin ob, 'behind', and caput, 'head'.
The cerebrum, telencephalon or endbrain is the largest part of the brain, containing the cerebral cortex as well as several subcortical structures, including the hippocampus, basal ganglia, and olfactory bulb. In the human brain, the cerebrum is the uppermost region of the central nervous system. The cerebrum develops prenatally from the forebrain (prosencephalon). In mammals, the dorsal telencephalon, or pallium, develops into the cerebral cortex, and the ventral telencephalon, or subpallium, becomes the basal ganglia. The cerebrum is also divided into approximately symmetric left and right cerebral hemispheres.
Beyrichoceras is a genus belonging to the goniatitid family Maxigoniatitidae that lived during the Mississippian Period
Ussuria is a genus of Lower Triassic ammonites with a smooth, involute discoidal shell with submonophyllic sutures, belonging to the ceratitid family Ussuriidae.
Aturia is an extinct genus of Paleocene to Miocene nautilids within Aturiidae, a monotypic family, established by Campman in 1857 for Aturia Bronn, 1838, and is included in the superfamily Nautilaceae in Kümmel 1964.
Sholakoceras is an extinct genus of nautiloid cephalopods from the Lower Permian of southern Russia, included in the Tainoceratacean family Rhiphaeoceratidae,. The shell of Shalakoceras is evolute with a perforate umbilicus. Whorl sections are subquadrate with the ventral and lateral sides flattened and ventral and umbilical shoulders rounded. Lateral areas bear short, slightly oblique ribs. sutures form broad ventral saddles with a slight, shallow lobe, very shallow lateral lobes, and a deep funnel-shaped dorsal lobe.
Stearoceras is an extinct genus of prehistoric nautiloids from the Lower Pennsylvanian - Lower Permian with a fair worldwide distribution.(Kümmel 1964)
Syringonautilidae is a family of Nautiloidea from the middle to late Triassic. Syringonautilidae comprise the last of the Trigonoceratoidea and are the source for the Nautilaceae which continued the Nautiloidea through the Mesozoic and into the Cenozoic right down to the recent. Syringonautilidae is a strictly Triassic family, derived early in the Triassic from the Grypoceratidae.
Grypoceratidae is the longest-lived family of the Trigonoceratoidea, or of the near equivalent Centroceratina; members of the Nautilida from the Upper Paleozoic and Triassic.
The Centroceratidae is the ancestral family of the Trigonoceratoidea and of the equivalent Centroceratina; extinct shelled cephalopods belonging to the order Nautilida
The Clydonautilidae are Middle and Upper Triassic nautiloid cephalopods, which are derivatives of the clydonautiloidean family Liroceratidae, that have generally smooth, involute, globular to compressed shells, characterized by a suture with prominent lobes and saddles. The family is known to contain five genera, These are:
Saffordoceras is an actinoceratid from the Middle Ordovician, found in eastern North America, characterized by a flattened venter; sutures with broad, deep ventral lobes and narrow lateral saddles; and subventral siphuncle with segments decreasing from about 0.3 to less than 0.2 the shell diameter. Saffordoceras is probably derived from Actinoceras. Related contemporary genera include Paractinoceras and Troostoceras
The Rhiphaeoceratidae are a small family of nautilids included in the superfamily Tainoceratoidea that comprises four very similar genera. These genera are characterized by a perforate umbilicus and little more than a single evolute coil. Whorl sections are oval, subquadrate, or subtrapezoidal. Sutures bend forward on the outer rim, forming wide shallow ventral saddles and dip strongly to the rear on the inner rim, forming deep dorsal lobes.
Pseudonautilidae is a family of Jurassic and Lower Cretaceous nautilid cephalopods belonging to the same superfamily as modern Nautilus, Nautilaceae, but forming a different branch from the family Nautilidae. Pseudonautilids, together with other nautilids, were contemporary with the ammonoids, which comprise an entirely different set of shelled cephalopod stocks more closely related to octopus and squid.
Neoglaphyrites is a goniatitid ammonite that lived during the latest Pennsylvanian and early Permian. Its shell is ellipsoidal and moderately involute; the umbilicus deep and typically less than 15 per cent of the shell diameter but in some species closer to 20 per cent. Delicate growth lines forming ventral and lateral sinuses and ventrolateral and dorsolateral salients have been found on Canadian Arctic specimens. The suture is characterized by the ventral lobe split into two broad prongs that are separated by a high median ventral saddle; prongs closely approximate the width of the first lateral lobe. The first lateral saddle is evenly rounded and is nearly symmetrical. The umbilical lobe is V-shaped and internal lobes are deep and narrow.
Grypoceras is a coiled nautiloid cephalopod from the Triassic of western North America, southern Asia, and Europe that belongs to the nautilid family Grypoceratidae. Named by Alpheus Hyatt in 1883, the shell of Grypoceras is essentially involute with a subtriangular cross section, widest across the umbilical shoulders, with flanks fairing toward a narrow flattened venter. Sutures on flanks are with smooth, deep lobes and with shallow ventral lobes.
Nannocetus is an extinct baleen whale belonging to the family Cetotheriidae.
Sturia is a genus of ceratitid ammonoids from the Lower Triassic with an ammonitic suture.
Proclydonautilus is a genus of nautiloids belonging to the Clydonautilidae known from the Upper Triassic of North America, Europe, and India.
This article includes a list of references, related reading, or external links, but its sources remain unclear because it lacks inline citations .(April 2013) |