Cotype is a term used in taxonomy and classification (especially in botany, zoology, and paleontology) to describe a type specimen designation. It has a specific historical meaning in scientific nomenclature, though its usage has shifted over time.
🌍 Definition
- Cotype (Taxonomy): Originally referred to any of the specimens cited in the original description of a new species when no single holotype was designated.
- Modern Usage: The term has largely been replaced by syntype under the rules of the International Code of Zoological Nomenclature (ICZN) and International Code of Nomenclature for algae, fungi, and plants (ICN).
🔑 Characteristics
- Historical Term: Used in older taxonomic literature before standardization of type specimen terminology.
- Multiple Specimens: A cotype set could include several specimens used collectively to define a species.
- Superseded by “Syntype”: Today, the correct term for multiple specimens cited without a holotype is syntype.
- Designation of Lectotype: Later, one specimen from the cotype/syntype series may be chosen as the lectotype to serve as the single name-bearing type.
📚 Scientific Significance
- Taxonomic Stability: Type specimens anchor species names to physical examples.
- Historical Records: Many museum collections still label specimens as “cotypes,” reflecting older practices.
- Clarification Needed: Modern taxonomists often reinterpret cotype labels as syntypes to align with current codes.
🛠 Examples
- Botany: A plant species described in the 19th century without a holotype may have several “cotypes” preserved in herbaria.
- Zoology: Fossil specimens described collectively as cotypes in early paleontology are now treated as syntypes.
- Museums: Collections often retain “cotype” labels for historical accuracy, even though the modern term is syntype.
✨ Summary
Cotype is an older taxonomic term for specimens used to define a species when no holotype was designated. Today, the correct term is syntype, with one specimen potentially later chosen as a lectotype.
