retinula

zoology

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July 13, 2026

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In zoology, a retinula refers to the neural receptor within a single facet of an arthropod's compound eye. Each retinula is part of an ommatidium, the visual unit of the compound eye. Within the retinula, specialized cells called retinula cells contain a light-receptive zone known as the rhabdom. The rhabdom is a rod-like structure composed of microvilli that capture incoming light rays. These cells are connected to the insect's brain via sensory axons, initiating nerve impulses when stimulated by light. Pigment cells also surround the retinula to prevent light from spreading to adjacent ommatidia, ensuring clearer visual input.123

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…the sense cell, called the retinula cell, and initiate the nerve impulse in the sensory axon. The light-receptive zone, or rhabdom, of the retinula cell commonly has a rodlike form; because it lies perpendicular to the surface, light passes lengthwise along it. In the simple eyes (ocelli) a lens-shaped area…
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…the sense cell, called the retinula cell, and initiate the nerve impulse in the sensory axon. The light-receptive zone, or rhabdom, of the retinula cell commonly has a rodlike form; because it lies perpendicular to the surface, light passes lengthwise along it. In the simple eyes (ocelli) a lens-shaped area…
Read More