The compound eye of Leptodora kindtii (Cladocera): An adaptation to planctonic life.

Research output: Contribution to journalArticle

Abstract

Each of the approximately 500 ommatidia in the compound eye of the cladoceran crustacean Leptodora kindtii has a crystalline cone consisting of five cells. Five retinula cells are also present, one of which contributes to the distal 1–2 μm of the rhabdom only; the other four retinula cells form a continuous rhabdom. Throughout the rhabdom its cross section displays two separate halves with the axis of the microvilli in one half perpendicular to that in the other (orthogonal pattern). Interferometric analysis of the refractive index of the crystalline cone revealed an inhomogeneous system with one distal and one proximal gradient. The gradient system was found to exclude rays entering from adjacent facets, thus maintaining the optical isolation. Consequently, these optics replace distal screening pigment, which is absent in the eye. The long and unscreened crystalline cones give rise to an almost transparent eye in conformity with the overall transparency of this planktonic animal.

The morphological characteristics of the eye of this species deviate from other cladoceran eyes, but the optical design closely resembles that of some pelagic marine amphipod crustaceans.

Details

Authors
Organisations
External organisations
  • Lund University
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Zoology

Keywords

  • Optics, Fine structure , Cladocera
Original languageEnglish
Pages (from-to)40-410
JournalCell and Tissue Research
Volume230
StatePublished - 1983
Publication categoryResearch
Peer-reviewedYes