Definition

Noun 1. A reptile of the genus Sphenodon, specifically Sphenodon punctatus: A rare, lizard-like reptile found only on certain islands off the coast of New Zealand. It is the sole surviving member of the order Rhynchocephalia, representing a very ancient lineage of reptiles.

Usage Examples

• Noun:
  • The sphenodon is often called a "living fossil" due to its primitive anatomical features.
  • Scientists study the sphenodon to understand early reptile evolution.
  • A key feature of the sphenodon is a vestigial third, or parietal, eye on the top of its head.

Advanced Usage

• In taxonomic context: The term is used to specify the genus within the order Rhynchocephalia.
  • The fossil record shows that the order Rhynchocephalia was once diverse, but today only the genus Sphenodon remains.

Variants and Related Words

• Tuatara (n): The common name for the reptile of the genus . While "sphenodon" is the scientific genus name, "tuatara" is the term used in general and conservation contexts.
  • The tuatara is a protected species in New Zealand.
• Rhynchocephalia (n): The order of reptiles to which the sphenodon belongs.
  • Rhynchocephalia is an ancient order distinct from lizards and snakes.

Synonyms

• Tuatara: This is the direct and most common synonym in non-scientific English.

Notes on Meaning

The word sphenodon refers specifically to the biological genus. In most general contexts, the common name tuatara is preferred. Using "sphenodon" typically indicates a formal or scientific context.

Noun

1. coextensive with the order Rhynchocephalia: tuataras