Stingray Tail Barb (Tail Spine)
Dasyatis sp. (likely Dasyatis say or relative) • Body fossil (Dermal spine); Vertebrate (Chondrichthyes)
Geological Period
Neogene (Miocene to Pliocene)
Estimated Age
2.5 to 15 million years
Preservation Type
Permineralization or Replacement (Phosphatization); the original calcium phosphate has been replaced by darker minerals giving it a black/dark brown coloration.
Condition Assessment
Fair; the specimen is weathered and smooth due to tumbling in the surf. Serrations (the 'teeth' of the barb) are heavily eroded, and the proximal attachment end is absent.
Taxonomic Classification
Phylum: Chordata, Class: Chondrichthyes, Order: Myliobatiformes, Family: Dasyatidae (Whiptail Stingrays)
Morphological Description
Elongated, slender, tapering calcified structure. Shows a characteristic central groove on the dorsal side and serrated lateral edges (though worn by wave action). The base is missing, and the tip is slightly rounded from erosion.
Rock Matrix
None (isolated specimen found in beach swash); typically originates from the Bone Valley Formation or Peace River Formation which consist of phosphate-rich sands and clays.
Formation & Location
Peace River Formation; Venice Beach, Sarasota, Florida, USA.
Size & Dimensions
Approximately 1.5 to 2.5 cm in length. This is a small specimen, likely a partial fragment from a larger ray or from a juvenile individual.
Value & Rarity
Estimated Market Value
$1.00 - $5.00 USD
Auction Estimate
Minimal (largely sold in bulk lots for $10 - $20 per pound)
Rarity Assessment
Common; Venice Beach is known as the 'Shark Tooth Capital of the World' and stingray barbs/dental plates are extremely frequent finds.
Scientific Significance
Common but useful for paleoecological reconstruction, indicating a shallow marine or estuarine environment typical of Florida during the Neogene.
Preparation Recommendations
Rinse in fresh water to remove salts; no chemical preparation required. Store in a dry, stable environment.
Notable Features
Deep dark coloration indicates successful mineralization in a phosphate-rich environment typical of Sarasota's Gulf Coast deposits.
Notes
Sarasota Fl Vince Beach