parasphenoid


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parasphenoid

[¦par·ə′sfē‚nȯid]
(vertebrate zoology)
A bone in the base of the skull of many vertebrates.
References in periodicals archive ?
The parasphenoid is a triradial bone observed in the anterior region of the pituitary fenestra.
Desarrollo embrionario del craneo en la lagartija vivipara Mabuya (Squamata: Scincidae)
Within the Neomorphinae, there are five characteristics that are shared by the group Geococcyx, Morococcyx and Neomorphus that differ from Tapera and Dromococcyx: the lateral length of the frontal is larger, the lateral process of the parasphenoid is reduced, the lateral orbitonasal foramen is larger, the bony lamella covering the nasal aperture is larger and the dorsal process of the nasal is absent.
When decisions on homologous structures cause ambiguous taxa relationships: the Neomorphinae (Aves, Cuculidae) example/ Interpretacoes de homologias primarias e ambiguidade nas posicoes filogeneticas dos taxons: o exemplo nos Neomorphinae (Aves, Cuculidae)
8] Posterior portion of parasphenoid (Costa 2005b) (CI: 0.
Relationships and taxonomy of the killifish genus Rivulus (Cyprinodontiformes: Aplocheiloidei: Rivulidae) from the Brazilian Amazonas river basin, with notes on historical ecology
3 times in base of the cranium; cranial spines well developed, directed straightly backward; preocular, postocular, tympanic and parietal spines always present supraocular, corneal and nuchal spines absent; parietal ridges high and naked; frontal ridges low but distinct, the space between them shallowly concave; supraocular edges low or depressed, as high as or lower than the frontal ridges; mesethmoid processes slightly elevated upward; base of cranium some-what curved; parietals separated or partly meeting; ventral process of the basisphenoid well developed, entirely meeting the parasphenoid.
An historical review of Sebastes Taxonomy and Systematics
The cultriform process of the parasphenoid is pointed and extends to the level of the neopalatines in E.
The relationships of an ensemble of guatemalan and mexican frogs (eleutherodactylus: leptodactylidae: amphibia)
Its counter element, the parasphenoid toothplate, has a concave occlusal surface (Fig.
Paleontology of the Glen Rose Formation (Lower Cretaceous), Hood County, Texas
However, this is not the case and in fact Laurin and Reitz (1995) used 'parasphenoid wings' to describe a condition where the wing is a raised, posterior extension of the parasphenoid that extends beyond its central depressed portion posteriorly.
The phylogenetic position of Nyctiphruretus acudens, a parareptile from the Permian of Russia/Posicion filogenetica de Nyctiphruretus acudens, un parareptil del Permico de Rusia
Vertical, complete laminar bony connection mesially to the eye between frontal, dorsally, and parasphenoid, ventrally.
Teleostean phylogeny based on osteological and myological characters/Filogenia de teleosteos basada en caracteristicas osteologicas y miologicas
Two flat elements, presumably the ventral surface of the parasphenoid (pa) and a small portion of the vomer (vo), are visible.
A fossil skull of the extant blue marlin (Makaira nigricans Lacepede, 1802) from the late Miocene of Orange County, California
A monogeneric atheriniform family with the parasphenoid concave rather than convex, parasphenoid myodomes present; mesethmoid morphology unique, nasal septum formed by ethmoid and mesethmoid; parietals not contributing to posttemporal fossa; anterior vertebral parapophyses with lateral ridges; interdorsals absent; cleithrum dorsal enclosure absent; membrane just posterior to genital opening; and pelvic posteromedial process elongate.
Descriptive anatomy of Iso rhothophilus (Ogilby), with a phylogenetic analysis of Iso and a redefinition of Isonidae (Atheriniformes)
Material: A parasphenoid (or), a right mandible (ch), two sacra (ch and sd), a left and a right ilium (rd and sd), and a femur (ch) [MSUVP 2052] identified by JAH.
Late Holocene (Little Ice Age Interval) microvertebrates from Mackinac County, Michigan
Both parasphenoid and basibranchial toothplates, referrable to the Paralbulinae, are known from the site.
Phyllodont (Paralbulinae) fish toothplates from the Lower Cretaceous Glen Rose Formation of central Texas
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