What is a Type Specimen?
When a scientist discovers and names a new species, they must designate a specific physical specimen — usually a pressed and dried plant mounted on a herbarium sheet — as the permanent reference for that name. This is the type specimen (holotype). If there is ever confusion about what species a name refers to, the type specimen is the ultimate authority.
Types of Type Specimens
Holotype
The single specimen designated by the original author as the name-bearing type. This is the most important type.
Isotype
A duplicate collected at the same time and place as the holotype — often deposited in a second herbarium for safety.
Paratype
Other specimens cited in the original description but not designated as the holotype.
Neotype
A replacement type designated when the original holotype is lost or destroyed.
Costa Rican Type Specimens
Historic Collections
Many Costa Rican tree species were first described from specimens collected by 19th-century botanists:
- Henri Pittier: Collected hundreds of type specimens during his work in Costa Rica (1887–1904).
- Paul Standley: Described numerous Costa Rican species based on National Museum collections.
- Adolfo Tonduz: His collections at the National Herbarium include many types.
Where They Are Housed
- Herbario Nacional de Costa Rica (CR): National collection of Costa Rican plant types.
- Field Museum (F), Chicago: Houses many Standley type specimens.
- US National Herbarium (US): Pittier's types deposited in Washington, D.C.
Why It Matters
- Taxonomic stability: Type specimens anchor species names permanently.
- Identification: When a tree cannot be identified, comparison with type specimens may resolve the question.
- Conservation: Some type specimens are the only known record of species that may be extinct.