Ceratotrichia
Definition
Flexible, unsegmented cartilaginous rods that form the internal skeleton of elasmobranch fins. Their number, branching pattern, and cross-sectional morphology are species-informative and the primary morphological target in processed fin identification.
- Structure
- Cartilaginous, unsegmented fin rods
- Found in
- Elasmobranch (shark and ray) fins
- Diagnostic features
- Number, branching pattern, cross-section
- Use
- Species identification in processed fin products
- Analysis level
- Morphological, no DNA required
Common questions
Why is ceratotrichia examination useful when DNA testing is also available?+
Processed fin products can be dried, boiled or otherwise altered in ways that degrade DNA, and morphological screening of the ceratotrichia rods is faster and cheaper for a first-pass species check before committing samples to genetic testing.
What limits ceratotrichia identification compared to DNA analysis?+
Morphological features can overlap between closely related species and require an experienced examiner, so a ceratotrichia finding is often treated as a screening result to be confirmed by DNA barcoding when a conclusive species call is needed.
Related terms
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