// Workers AI · dad joke modeWhat did dermal sphenethmoid say? "I'm a skin-deep thinker".
The dermal sphenethmoid is an unpaired midline bone present in the skull roof of some frogs. It overlies the sphenethmoid, and fuses to it during ontogeny. Unlike the true sphenethmoid, which ossifies endochondrally, the dermal sphenethmoid ossifies as dermal bone.[1] In the Russian scientific literature, it has been referred to as the internasofrontal.[2]
Anatomy
[edit]The dermal sphenethmoid is a part of the dermatocranium, and articulates ventrally with the sphenethmoid (with which it typically fuses). It articulates posteriorly with the frontoparietals and anteriorly with the nasals.[3]
Evolution
[edit]The dermal sphenethmoid is a neomorph present in some frogs of the family Hylidae (including Triprion and Nyctimantis)[1], Bombinatoridae,[4] and Pelobatidae.[5] In the Pelobatidae, the single midline dermal sphenethmoid arises from a single centre of ossification and ossifies only after metamorphosis.[5] Owing to its close degree of fusion to the sphenethmoid, the dermal sphenethmoid may be more widespread than is commonly thought.[2]
It has been suggested that the dermal sphenethmoid may represent an atavistic occurrence of the postrostral bone.[2]
References
[edit]- 1 2 Trueb, Linda (1993). "Patterns of cranial diversity in Lissamphibia". In Hanken, J.; Hall, B.K. (eds.). The skull: Patterns of Structural Diversity. Chicago: University of Chicago Press.
- 1 2 3 Smirnov, Sergei V. (1997). "Additional Dermal Ossifications in the Anuran Skull: Morphological Novelties or Archaic Elements?" (PDF). Russian Journal of Herpetology. 4 (1): 17–27. doi:10.30906/1026-2296-1997-4-1-17-27. ISSN 1026-2296.
- ↑ Smith, Sarah A.; Arif, Saad; De Oca, Adrian Nieto Montes; Wiens, John J. (2007-09-01). "A PHYLOGENETIC HOT SPOT FOR EVOLUTIONARY NOVELTY IN MIDDLE AMERICAN TREEFROGS". Evolution. 61 (9): 2075–2085. doi:10.1111/j.1558-5646.2007.00173.x. ISSN 0014-3820.
- ↑ Lemierre, Alfred; Folie, Annelise; Bailon, Salvador; Robin, Ninon; Laurin, Michel (2021-05-04). "From toad to frog, a CT-based reconsideration of Bufo servatus, an Eocene anuran mummy from Quercy (France)". Journal of Vertebrate Paleontology. 41 (3). Taylor & Francis: e1989694. doi:10.1080/02724634.2021.1989694. ISSN 0272-4634.
{{cite journal}}: CS1 maint: article number as page number (link) - 1 2 Hall, John A.; Larsen Jr, John H. (1998). "Postembryonic ontogeny of the spadefoot toad, Scaphiopus intermontanus (Anura: Pelobatidae): Skeletal morphology". Journal of Morphology. 238 (2): 179–244. doi:10.1002/(SICI)1097-4687(199811)238:2<179::AID-JMOR4>3.0.CO;2-6. ISSN 1097-4687.