Search results for "Enameloid"

2020

Skeletal remains in archaeological strata are often assumed to be of similar ages. Here we show that combined Sr and O isotope analyses can serve as a powerful tool for assessing fish provenance and even for identifying fossil fish teeth in archaeological contexts. For this purpose, we established a reference Sr and O isotope dataset of extant fish teeth from major water bodies in the Southern Levant. Fossil shark teeth were identified within Iron Age cultural layers dating to 8–9th century BCE in the City of David, Jerusalem, although the reason for their presence remains unclear. Their enameloid 87Sr/86Sr and δ18OPO4 values [0.7075 ± 0.0001 (1 SD, n = 7) and 19.6 ± 0.9‰ (1 SD, n = 6), res…

Lonchidion derenzii, sp. nov., a new lonchidiid shark (Chondrichthyes, Hybodontiforms) from the Upper Triassic of Spain, with remarks on lonchidiid e…

2016

Lonchidiidae Herman, 1977, represents one of the most diverse and controversial families of Hybodontiformes, the sister group of Neoselachii (i.e., modern sharks, skates, and rays). It was initially erected as a monogeneric family including only Lonchidion Estes, 1964, a genus of small euryhaline hybodonts from the Mesozoic. Recently, Cappetta (2012) recognized up to eight genera within the family: Baharyodon, Diplolonchidion, Vectiselachos, Hylaeobatis, Isanodus, Parvodus,Lissodus, andLonchidion, although the content of the family is still under discussion (see, e.g., Rees, 2008; Khamha et al., 2016). Major discrepancies concern the phylogenetic relationships between Lonchidion and Lissodu…

New insights into the enameloid microstructure of batoid fishes (Chondrichthyes)

2016

Chondrichthyan teeth are capped with a hypermineralized tissue known as enameloid. Its microstructure displays a hierarchical organization that has increased in structural complexity from a homogenous single-crystallite enameloid (SCE) in early Chondricthyans to the complex multilayered enameloid found in modern sharks (consisting of bundles of crystallites arranged in intriguing patterns). Recent analyses of the enameloid microstructure in batoid fishes, focused on Myliobatiformes and fossil taxa, point to the presence of a bundled (or fibred) multilayered enameloid, a condition proposed as plesiomorphic for Batoidea. In this work, we provide further enameloid analysis for a selection of t…

Tooth oxygen isotopes reveal Late Bronze Age origin of Mediterranean fish aquaculture and trade

2018

AbstractPast fish provenance, exploitation and trade patterns were studied by analyzing phosphate oxygen isotope compositions (δ18OPO4) of gilthead seabream (Sparus aurata) tooth enameloid from archaeological sites across the southern Levant, spanning the entire Holocene. We report the earliest evidence for extensive fish exploitation from the hypersaline Bardawil lagoon on Egypt’s northern Sinai coast, as indicated by distinctively high δ18OPO4 values, which became abundant in the southern Levant, both along the coast and further inland, at least from the Late Bronze Age (3,550–3,200 BP). A period of global, postglacial sea-level stabilization triggered the formation of the Bardawil lagoon…

2019

Here we explore the carbon and oxygen isotope compositions of the co-existing carbonate and phosphate fractions of fish tooth enameloid as a tool to reconstruct past aquatic fish environments and harvesting grounds. The enameloid oxygen isotope compositions of the phosphate fraction (δ18OPO4) vary by as much as ~4‰ for migratory marine fish such as gilthead seabream (Sparus aurata), predominantly reflecting the different saline habitats it occupies during its life cycle. The offset in enameloid Δ18OCO3-PO4 values of modern marine Sparidae and freshwater Cyprinidae from the Southeast Mediterranean region vary between 8.1 and 11.0‰, similar to values reported for modern sharks. The mean δ13C …

Pseudodalatias henarejensisnov. sp. a new pseudodalatiid (Elasmobranchii) from the Middle Triassic of Spain

2009

ABSTRACT Pseudodalatiids, a chondrichthyan family of uncertain phylogenetic affinities, have been hitherto exclusively known from the tooth-based species Pseudodalatias barnstonensis (Sykes, 1971), which has a stratigraphic range restricted to the Upper Triassic of Europe. Pseudodalatias presents a characteristic dentition which allows it to hold and cut its prey, showing a neoselachian design, but lacking the triple-layered enameloid microstructure of neoselachian teeth. The discovery of Pseudodalatias henarejensis nov. sp. in the Ladinian of Spain extends the stratigraphical range and the palaeogeographical distribution of this family. This new species also demonstrates that a cutting-clu…

Enameloid microstructure in the oldest known chondrichthyan teeth

2009

Botella, H., Donoghue, P.C.J and Martinez-Perez, C. 2009. The enameloid microstructure of the oldest known chondrichthyan teeth. — Acta Zoologica (Stockholm) 90 (Suppl. 1): 103‐108 Previous studies on tooth enameloid microstructure in several chondrichthyan taxa spanning the phylogeny of the group provided support for the homology of chondrichthyan tooth enameloid. This hypothesis requires that a single crystallite enameloid (SCE) monolayer must be present in the teeth of the most primitive chondrichthyan. However, the dental microstructure of the earliest sharks has yet to be investigated. We have studied the tooth enameloid microstructure of the two oldest tooth-bearing shark species curr…