An aptychus is a type of marine fossil. It is a hard anatomical structure, a sort of curved shelly plate, now understood to be part of the body of an ammonite...

postulated to have been a jaw apparatus. The plates are collectively termed the aptychus or aptychi in the case of a pair of plates, and anaptychus in the case...

ammonites (extinct shelled cephalopods), a calcareous structure known as the aptychus (plural aptychi) existed. When these were first described they were thought...

lacks an aptychus, a biomineralized plate which is proposed to act as an operculum which closes the shell to protect the body. However, aptychus-like plates...

shell is often the only mineralised part of a mollusc (however also see Aptychus and operculum). The shells are usually preserved as calcium carbonate –...

or less tabulate venter, with lateral or ventrolateral tubercles. The aptychus is double valved with a concentrically ribbed surface. "Paleobiology Database...

Somalia and the western North Atlantic. In Mexico, the first records of Aptychus latus (= Laevaptychus latus) are provided from the Upper Jurassic of the...

An operculum also covers the eggs of stick insects an other insects. Aptychus: A structure in ammonites which usually consists of two plates, and which...

scaphopods. The word "sculpture" is also applied to surface features of the aptychus of ammonites, and to the outer surface of some calcareous opercula of marine...

Hectocotylus Tentacles Carpus Dactylus Manus Suckers and hooks Buccal region Aptychus Beak Odontophore Radula Spadix and antispadix Occipital region Nuchal crest...

An aptychus with the name Trigonellites latus, from the Kimmeridge Clay Formation...

†T. curvirostris Schlotheim, 1836 †T. simplex? Schlotheim, 1863 vide Goldfuss, 1863 Synonyms Aptychus von Meyer, 1831 Lyrodon simplex? Schlotheim, 1863...

Germany and Wealden of Hanover; the limestones and shales of Teschen; the Aptychus and Pygope diphyoides marls of Spain, and the Petchorian formation of Russia...

the formation was described in more detail by Fuchs, Weis & Thuy (2024). Aptychus sp. Belemnitida indet. Beloteuthis sp. Bositra buchi Bositra sp. Caturus...

it lay on its belly, an interpretation that is further supported by an aptychus (body part of an ammonite) found within the slab; aptychi are almost always...

The Aptychus is a mysterious piece of ammonite anatomy....

Ueber den Jurakalk von Kurowitz in Mähren und über darin vorkommenden Aptychus imbricatus, 1841 – On the Jurassic limestone of Kurowitz in Mähren. Geognostische...

Epaspidoceras lusitanicum, from Charente-Maritime. Specimen showing the aptychus, on display at Galerie de paléontologie et d'anatomie comparée, Paris Scientific...

Aptycus are bivalved and very durable, and in the "lower Kimmeridgian form Aptychus beds, containing few or no ammonites". (Kimmeridgian is middle Upper Jurassic...

(1920) Ammonite species Aptychus cristobalensis (1921) Ammonite species Aptychus cubanensis (1921) Ammonite species Aptychus pimientensis (1921) Ammonite...

conformably overlain by the so-called Aptychus Limestone of the Ammergau Formation. The changeover to the Aptychus Limestone is gradual. The lower contact...

the arthropod Spathiocaris but in 2017 reinterpreted to be an ammonoid aptychus, may also be found. Fossil fish teeth, scales, and sometimes bones or armor...

Moldova-Sulița IV botanic 116,40 Bila-Lala Reservation Cârlibaba IV mixt 325,10 The Aptychus layer from Pojor Fundu Moldovei IV palaeontological 1 Tinovul Găina - Lucina...

feebly keeled. Sutures are simple with phylloid saddle endings in some. The aptychus is single, found in sutu in Psiloceras Badouxia Guex and Taylor, 1976 Caloceras...

discovered Perisphinctes Kobelti from the Oxfordian age. He collected Aptychus (from the lamellosi group), Peltoceras transversarium, Rhacophyllites tortisulcatus...

venter, is typically hollow. Sutures vary from simple to complex. The aptychus is shiny with coarse folds (Cornaptychus). Sonniniidae are included in...

(2023). A specimen of Prionocyclus germari found in association with an aptychus referred to the genus Praestriaptychus is described from the Turonian strata...

Cretaceous Angertal Formation Devonian Angulatensandstein Formation Jurassic Aptychus Beds Formation Jurassic Arietenkalk Formation Jurassic Aspidoides Bank...