anapsid reptile
Definition
- Noun:
- An extinct or extant reptile characterized by a skull lacking temporal openings: An "anapsid reptile" is a member of a primitive group of reptiles defined by a skull structure that has no holes (fenestrae) in the temporal region behind the eye sockets. This anatomical feature is considered the ancestral condition for reptiles. While most reptiles in this group are extinct, modern turtles are classified as surviving members.
Usage Examples
- Noun:
- The fossil record shows that the anapsid reptile was one of the earliest reptilian forms.
- Turtles are unique among living reptiles because they are considered an anapsid reptile.
Advanced Usage
- In phylogenetic classification: The term "anapsid reptile" is used in scientific taxonomy and evolutionary biology to describe reptiles based on this specific skull morphology, contrasting them with diapsid reptiles (like lizards and birds) and synapsids (like mammals).
- The debate continues over whether turtles are true anapsid reptiles or if they secondarily lost their temporal openings.
Variants and Related Words
- Anapsid (adj/n): Pertaining to or being a member of this reptile group.
- The anapsid skull condition is a key diagnostic feature.
- Anapsida (n): The formal taxonomic name for the group or subclass that includes these reptiles.
Synonyms
- Parareptile: A term sometimes used in more modern cladistic classifications for a group of extinct reptiles traditionally considered anapsids.
- Stem reptile: A more general, informal term for very early, primitive reptiles, which often had anapsid skulls.
Related Terms (Not Phrasal Verbs or Idioms)
- Diapsid: A reptile with two pairs of temporal openings in the skull (e.g., lizards, snakes, crocodiles, birds).
- Synapsid: An amniote with a single pair of temporal openings, a group that includes mammals and their extinct relatives.
- Temporal fenestra: The opening(s) in the skull behind the eye orbit that define these major amniote groups.
Noun
-
primitive reptile having no opening in the temporal region of the skull; all extinct except turtles
Khám phá thêm
Các từ liên quan
Từ đồng nghĩa
Từ trái nghĩa
