subclass anapsida

Học thuật
Thân thiện
subclass anapsida

A turtle, a member of the subclass Anapsida, rests on a sunlit riverbank.

Definition

Noun: - A taxonomic subclass of reptiles characterized by having a skull without temporal openings (anapsid condition). This group traditionally includes turtles and various extinct forms from the Permian period and earlier, representing some of the most ancient reptile lineages.

Usage
  • The term is used in scientific, particularly paleontological and zoological, contexts to classify a specific group of reptiles based on skull morphology.
  • Example: "The subclass Anapsida is distinguished by the absence of fenestrae, or openings, behind the eye sockets in the skull."
  • Example: "Turtles are often placed within the subclass Anapsida, though some modern classifications debate this based on genetic evidence."
Advanced Usage
  • In modern phylogenetic systematics, the traditional grouping "Anapsida" is sometimes considered paraphyletic. The term may be used in historical or specific morphological contexts rather than as a strict clade name.
  • Example: "When discussing skull evolution, the anapsid condition of the subclass Anapsida is contrasted with the diapsid condition of lizards and birds."
Variants and Related Words
  • Anapsid (noun/adjective): Referring to an organism belonging to or having the characteristics of the subclass Anapsida.
    • Example: "The anapsid skull structure is a primitive trait among reptiles."
  • Anapsida: The formal taxonomic name, often used interchangeably with "subclass Anapsida."
Synonyms
  • Anapsid reptiles: A descriptive synonym emphasizing the defining skull characteristic.
  • Primitive reptiles (in a specific taxonomic sense): A more general term, but can be contextually equivalent when referring to this basal group.
Related Terms (Not Phrasal Verbs or Idioms)
  • Diapsida: The subclass of reptiles (including lizards, snakes, crocodilians, and birds) characterized by two temporal openings in the skull, often contrasted with Anapsida.
  • Synapsida: The subclass of reptiles (including mammals and their extinct relatives) characterized by a single temporal opening, another point of contrast in skull evolution.
  • Chelonia/Testudines: The order that includes turtles and tortoises, the primary living group historically classified under Anapsida.
subclass anapsida

A turtle, a member of the subclass Anapsida, rests on a sunlit riverbank.

Noun
  1. oldest known reptiles; turtles and extinct Permian forms

Từ đồng nghĩa