Rays and Skates by Amy Allinson

Phylogeny

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Taxonomy

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Kingdom: Animalia

Phylum: Chordata

Class: Chondrichthyes

Subclass: Elasmobranchii

Superorder: Batoidea

Order: Rajiformes

Stingray ecology

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On average live between 15-25
Grow up to 6.5 feet
Camouflaged to the sea floor
Eyes on the dorsal side
Carnivore (primarily molluscs)

The skeleton of a stingray, (Urobatis jamaicensis)

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Archaeological examples

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Maya Bloodletting

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Use of Stingray spines for ritual purpose. They have been recovered from many burials and catches. Link to Bloodletting has been established through appearance in auto sacrifice imagery and polychrome vessels.
Venom glands extend along ventro-lateral grooves. Mucus and pieces of the spine can be introduced to the wound when cut by the dentate margins.
Tissue necrosis occurs in roughly two-thirds of puncture wounds from stingrays. However, it can also cause effects such as pain, inflammation and death.
The effects caused by the spines has opened interpretation for the use in Maya rituals.
Iconographic association linking stingrays with the underworld.
Spines associated with male burials likley part of a personal bloodletting kit which has been linked to penis perforating. Whereas spines in female burials has been linked to cutting other areas such as tongue, cheeks and earlobes.

Taphonomy

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Cartilaginous fish usually poorly represented in archaeological assemblages due to poor preservation.
Documentation biased towards rays with large/ recognisable denticles.
Archaeological sites in Belgium devised a system using 1mm and 2mm sieves that yields dermal denticles of more species than previously. For example, it can produce individual teeth from Rajidae (skates), whereas before they could primarily identify the thornback ray.

Importance to humans

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Historical records show evidence for medieval and postmedieval trading.
Played an important role in coastal fisheries around the world.

Stingray

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Skate

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Dermal Denticles

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Two types:

Prickles
Thorns

Prickles

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These are smaller and cover the entire body.

There are two types:

Myrmecoid - Wider anterior on the crown
Spiny - Straight

Thorns

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These are larger than prickles. If they have a heavy base they can be referred to as 'buckles'.

It is not possible to distinguish thorns on different areas on the body due to the shape only gradually changing.

Thornback Ray dermal denticles

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Stingray taxonomy

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Domain: Eukaryota

Kingdom: Animalia

Phylum: Chordata

Class: Chondrichthyes

Superorder: Batoidea

Order: Myliobatiformes

Suborder: Myliobatoidei

Elasmobranchs

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Sharks, Skates and Rays
Comprise less than 5% of modern fish species
Cartilaginous skeleton
Dermal denticles
Skull without sutures
Mouth and nostril on the underside of the head
teeth continuously replaced or grow in fiscal plates

Chondrichthyes

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Sharks, Skates, Rays and Ratfish
Cartilaginous
Over 900 known species
Live in oceans and frehswater

Saw fish

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Sawfish in the Arabian region

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Rich cultural associations between coastal people and Saw fish
Sawfish vertebral centra
in human food remains indicate the widespread
distribution of sawfish along the entire Arabian
coast of the Gulf

Sawfish Rostrum

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Sawfish are marine rays in the Pristidae family
Two gena and seven species
Rostrum has same number of teeth on each side
Teeth are dorsoventrally flattened with the shape of an equilateral triangle
Lacks barbels
Used for defence and feeding

Use by hunter-gatherers

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Twelve rostral teeth analysed
Classified according to modification
Found in four of the seven shell mounds

References

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Gonzalez, M. M. B. (2005). Use of Pristis spp. (Elasmobranchii: Pristidae) by Hunter-Gatherers on the Coast of São Paulo, Brazil. Neotropical Ichthyology, 3.

Gravendeel, R., Van Neer, W. and Brinkhuizen, D. (2002). An identification key for dermal denticles of Rajidae from the North Sea. International Journal of Osteoarchaeology, 12(6), 420-441.

Haines, H. R., Willink, P. W. and Maxwell, D. (2008). Stingray Spine Use and Maya Bloodletting Rituals: A Cautionary Tale. Latin American Antiquity, 19(1), 83-98.

Moore, A. B. M. (2015). A review of sawfishes (Pristidae) in the Arabian region: diversity, distribution, and functional extinction of large and historically abundant marine vertebrates. Aquatic Conservation: Marine and Freshwater Ecosystems, 25(5), 656-677.

Rick, T. C., et al. (2002). Evaluating the Economic Significance of Sharks, Skates, and Rays (Elasmobranchs) in Prehistoric Economies. Journal of Archaeological Science, 29(2), 111-122.

Villalobos-Segura, E., et al. (2022). The Phylogeny of Rays and Skates (Chondrichthyes: Elasmobranchii) Based on Morphological Characters Revisited. Diversity, 14(6), 456.