The proboscis ciliation of the echiuran Bonellia viridis

1979 ◽  
Vol 59 (2) ◽  
pp. 377-384 ◽  
Author(s):  
V. Jaccarini ◽  
P. J. Schembri
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Quantitative Analysis ◽  
Light And Electron Microscopy ◽  
Neck Region ◽  
Dorsal Surface ◽  
Food Particle ◽  
Particle Uptake ◽  
Transmission Electron ◽  
Definite Pattern

Special club-shaped cilia with an expanded tip are seen by both light and electron microscopy on the proboscis of Bonellia viridis in addition to the usual filamentous cilia. Using transmission electron microscopy the club tip is seen to consist of a distally curled axoneme enclosed within a sac-like expansion of the ciliary membrane. The axoneme may describe up to two complete loops inside the membrane sac or may occasionally follow an S-shaped course.A quantitative analysis of the distribution on the proboscis of both filamentous and club cilia is made. No discrete ciliary tracts are present. However, there is a definite pattern of ciliary density distribution. The cilia are densest on both the dorsal and ventral surfaces of the distal fringe of the proboscis. The dorsal fringe cilia are concerned with locomotion and the ventral cilia with food particle uptake. The club cilia are confined to the terminal lobes and neck region of the proboscis. The dorsal surface of the proboscis posterior to the fringe is virtually non-ciliated. The functional significance of the club cilia is discussed.

scholarly journals Giardia muris and Giardia duodenalis groups: ultrastructural differences between the trophozoites

1989 ◽  
Vol 31 (4) ◽  
pp. 242-247 ◽  
Author(s):  
Maria Inês L. Sogayar ◽  
Elisa Aparecida Gregório
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Giardia Duodenalis ◽  
Dorsal Surface ◽  
Distal Extremity ◽  
Transmission Electron ◽  
Marginal Plate ◽  
Marginal Plates ◽  
Giardia Muris ◽  
Rats And Mice

Trophozoites of the Giardia muris group from hamsters, domestic rats and mice and of the Giardia duodenalis group from hamsters and domestic rats were examined by transmission electron microscopy. The basic ultrastructure of the trophozoites was similar. Differences were shown in the morphology of the ventrolateral flange of the trophozoites of Giardia muris and Giardia duodenalis groups. Marginal plates are less developed in the species of the Giardia duodenalis group. In this group, the distal extremity of the lateral flange is short and thick and the marginal plate does not penetrate into the distal extremity of the flange. In the Giardia muris group, the ventro-lateral flange is well developed and narrow and the marginal plate penetrates the distal extremity of the flange. The osmiophilic lamella, which accompanies the dorsal surface of the marginal plate is seen only in the Giardia muris group.

Scale structure and taxonomy of some species of Raphidocystis, Raphidiophrys, and Pompholyxophrys (Heliozoea) including descriptions of six new taxa

1985 ◽  
Vol 63 (8) ◽  
pp. 1944-1961 ◽  
Author(s):  
K. H. Nicholls ◽  
M. Dürrschmidt
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
New Zealand ◽  
Light Microscopy ◽  
Light And Electron Microscopy ◽  
Scale Structure ◽  
Taxonomic Descriptions ◽  
Transmission Electron ◽  
New Information ◽  
Freshwater Habitats

Sixteen taxa of the genera Raphidocystis, Raphidiophrys, and Pompholyxophrys from freshwater habitats in Canada, Chile, and New Zealand were studied by light and electron microscopy. Six taxa are described as new: Raphidocystis glabra, Raphidiophrys minuta, Raphidiophrys orbicularis ssp. orbicularis, R. orbicularis ssp. ovalis, Pompholyxophrys stellata, and P. ossea. New information on scale structure and arrangement based on scanning and transmission electron microscopy amplifies the taxonomic descriptions of Raphidiophrys ambigua, R. pallida, R. elegans, R. intermedia, R. marginata, R. symmetrica, Pompholyxophrys punicea, P. exigua, and P. ovuligera, which were previously imperfectly known by light microscopy only.

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