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Updated: Jul 12, 2026
08:33
Determination of Photoreceptor Cell Spectral Sensitivity in an Insect Model from In Vivo Intracellular Recordings
Published on: February 26, 2016
Insect photoreceptor: an internal ocellus is present in sphinx moths
Science (New York, N.Y.)
|August 27, 1971
Summary
Adult sphinx moths possess internal ocelli, homologous to external ones found in other insects. Studies on Manduca sexta reveal these structures respond to light, confirming their ocellar function.
Area of Science:
- * Entomology
- * Comparative physiology
- * Insect neurobiology
Background:
- * Adult sphinx moths (anocellate moths) lack external ocelli.
- * However, structures homologous to ocelli have been identified in species like Manduca sexta.
- * The nature and function of these homologous structures remained unclear.
Purpose of the Study:
- * To investigate the histological and electrophysiological characteristics of ocellar homologous structures in Manduca sexta.
- * To determine if these structures function as internal ocelli.
Main Methods:
- * Histological examination of the homologous structures in Manduca sexta.
- * Electrophysiological recordings to assess responses to light stimuli.
Main Results:
- * Histological analysis revealed structural similarities between the observed structures and the ocelli of other insects.
- * Electrophysiological studies demonstrated that these structures respond to light, similar to the electroretinogram of external ocelli.
Conclusions:
- * The combined histological and electrophysiological evidence strongly suggests that these structures are indeed internal ocelli.
- * This finding challenges the notion that all adult sphinx moths are anocellate.
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