Retinal and optical adaptations for nocturnal vision in the halictid bee Megalopta genalis

Research output: Contribution to journalArticle


The apposition compound eye of a nocturnal bee, the halictid Megalopta genalis, is described for the first time. Compared to the compound eye of the worker honeybee Apis mellifera and the diurnal halictid bee Lasioglossum leucozonium, the eye of M. genalis shows specific retinal and optical adaptations for vision in dim light. The major anatomical adaptations within the eye of the nocturnal bee are (1) nearly twofold larger ommatidial facets and (2) a 4-5 times wider rhabdom diameter than found in the diurnal bees studied. Optically, the apposition eye of M. genalis is 27 times more sensitive to light than the eyes of the diurnal bees. This increased optical sensitivity represents a clear optical adaptation to low light intensities. Although this unique nocturnal apposition eye has a greatly improved ability to catch light, a 27-fold increase in sensitivity alone cannot account for nocturnal vision at light intensities that are 8 log units dimmer than during daytime. New evidence suggests that additional neuronal spatial summation within the first optic ganglion, the lamina, is involved.


Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Cell Biology


  • visual system, apposition compound eye, retina, Megalopta genalis (Insecta), structure, nocturnal vision, dim light
Original languageEnglish
Pages (from-to)377-390
JournalCell and Tissue Research
Issue number3
Publication statusPublished - 2004
Publication categoryResearch

Related research output

Birgit Greiner, 2005, Lund Unversity, Department of Cell and Organism Biology. 140 p.

Research output: ThesisDoctoral Thesis (compilation)

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