ocellus

/ou'seləs/
Học thuật
Thân thiện
ocellus

A butterfly rests with its wings open, showing a prominent ocellus on each hindwing.

Definition
  1. Noun:
    • A simple eye, or an eye with a single lens: In zoology, an ocellus is a type of simple visual organ found in many invertebrates, such as insects and some other arthropods. It is distinct from a compound eye.
    • An eyelike spot or marking: In biology, an ocellus is a circular, often colorful marking that resembles an eye, commonly found on the wings of butterflies, moths, or the bodies of other animals.
Examples of Usage

  • Noun (Simple Eye):

    • The insect's head bears two compound eyes and three ocelli.
    • Ocelli are sensitive to light intensity but do not form detailed images.

  • Noun (Eyelike Marking):

    • The butterfly's wings have prominent ocelli to scare away predators.
    • The peacock feather is famous for its beautiful ocelli.
Advanced Usage

  • In Entomology: The term is used precisely to describe the simple eyes located on the heads of insects, arachnids, and myriapods.

    • The dorsal ocelli of the dragonfly are thought to aid in flight stabilization.

  • In Lepidopterology (Study of Butterflies and Moths): Refers specifically to the eye-spot patterns.

    • The number and arrangement of ocelli are key identification features for some moth species.
Variants and Related Words

  • Ocellar (adjective): Pertaining to an ocellus.

    • The ocellar region of the insect's head was examined.

  • Ocellated (adjective): Having ocelli or eyelike spots.

    • The ocellated lizard gets its name from the blue spots along its body.
Synonyms
  • Simple eye: For the visual organ sense.
  • Eyespot: For the marking sense.
  • Stemmata (plural): A term sometimes used for the simple eyes of insect larvae.
Notes on Meaning
  • The two primary meanings are distinct but related through the concept of an "eye-like" structure—one is a functional sensory organ, and the other is a decorative or defensive marking that mimics an eye.
  • The plural form is ocelli (pronounced /oʊˈsɛlaɪ/ or /əˈsɛli/).
ocellus

A butterfly rests with its wings open, showing a prominent ocellus on each hindwing.

Noun
  1. an eyelike marking (as on the wings of some butterflies); usually a spot of color inside a ring of another color
  2. an eye having a single lens

Từ đồng nghĩa