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Zoomorphology

, Volume 115, Issue 4, pp 221–227 | Cite as

Ocelli in a Cnidaria polyp: the ultrastructure of the pigment spots in Stylocoronella riedli (Scyphozoa, Stauromedusae)

  • Michael J. F. Blumer
  • Luitfried v. Salvini-Plawen
  • Reinhard Kikinger
  • Thomas Büchinger
Original Article

Abstract

Within the Cnidaria, the occurrence of ocelli at the polyp stage is only known in the species of Stylocoronella (Scyphozoa, Stauromedusae). The light-sensitive organs of S. riedli are ultrastructurally investigated. In this interstitial-living species, each of the up to 24 ocelli is composed of between seven and nine monociliary sensory cells and between one and four pigment cells. A striking feature of the photoreceptive cilia is their peculiar axonemal pattern. This is expressed (a) by the presence of a third central microtubule at a certain point and (b) by the balloon-like swelling of the distal portion of the cilium, with clearly scattered microtubules in this area. Although the polyps of S. riedli show no distinct reaction to light stimuli, the ultrastructural results corroborate the hypothesis that these organs are light-sensitive organs. The possible function of the pigment granules is discussed.

Keywords

Developmental Biology Striking Feature Distal Portion Sensory Cell Light Stimulus 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Abbreviations

bb

basal body

c

cilium

co

collar

csv

crescent-shaped vesicle

cv

clear vesicle

dcv

dense-core vesicles

k

kinetosome

m

mitochondrion

mvb

multivesicular body

n

nucleus

oc

ocellus

pc

piment cell

pg

pigment granule

sc

sensory cell

sr

striated rootlet

v

vesicle

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Copyright information

© Springer-Verlag 1995

Authors and Affiliations

  • Michael J. F. Blumer
    • 1
  • Luitfried v. Salvini-Plawen
    • 1
  • Reinhard Kikinger
    • 1
  • Thomas Büchinger
    • 1
  1. 1.Abteilung für Systematische ZoologieInstitut für Zoologie der Universität WienWienOsterreich

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