hemimetabolous

Thân thiện

A dragonfly nymph crawls along a pond floor, a hemimetabolous insect.

Definition

1. Adjective:
   • Relating to incomplete metamorphosis in insects: Describes a type of insect development where the young (nymphs) resemble the adult form but are smaller, lack wings, and are not sexually mature. The change to the adult stage occurs through a series of molts without a pupal stage.

Usage

• The term is used specifically in entomology (the study of insects) to classify and describe insect life cycles.
• It is typically applied to insects like grasshoppers, true bugs, and dragonflies, whose juveniles live in the same environment (often terrestrial) as adults. The reference to "aquatic young" in some definitions is characteristic of specific orders like mayflies (Ephemeroptera) but is not universal to all hemimetabolous insects.

Examples

• Adjective:
  • Grasshoppers are hemimetabolous insects; their nymphs look like small, wingless adults.
  • The hemimetabolous development of a dragonfly involves an aquatic nymph stage, called a naiad.

Advanced Usage

• In scientific classification: The term is part of a formal dichotomy with "holometabolous" (complete metamorphosis).
  • The order Orthoptera is characterized by hemimetabolous metamorphosis.

Variants and Related Words

• Hemimetabolism (n): The condition of undergoing incomplete metamorphosis.
  • Hemimetabolism is a common trait in many ancient insect orders.
• Hemimetabolically (adv): In a hemimetabolous manner.
  • The insect develops hemimetabolically.
• Hemimetaboly (n): Another term for hemimetabolism.

Synonyms

• Hemimetamorphic: Having incomplete metamorphosis.
• Paurometabolous: A more specific term often used interchangeably for terrestrial hemimetabolous insects where the nymph and adult habitats are similar (e.g., grasshoppers), in contrast to "hemimetabolous" insects with aquatic nymphs (e.g., mayflies).

Antonyms

• Holometabolous: Undergoing complete metamorphosis (egg, larva, pupa, adult), as seen in butterflies, beetles, and flies.
• Ametabolous: Undergoing little or no metamorphosis, with the young resembling the adult except in size and sexual maturity (e.g., silverfish).

Học thuật

Adjective

1. (of an insect with aquatic young) undergoing incomplete metamorphosis in which the young does not resemble the adult

Từ đồng nghĩa

• hemimetabolic
• hemimetamorphous
• hemimetamorphic