Figs 29-43 - uploaded by Daniel Wujek
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Light and electron micrographs of Lagynion delicatulum zoospores and settling cells. Figs 29-39. Electron micrographs of zoospores. Fig. 29. Longitudinal section through basal bodies 1 and 2, showing the basal body angle and the deltoid striated band (arrow). Scale bar represents 250 nm. Figs 30, 31. Cross-sections of basal body 2, from a series, viewed from the anterior end of the cell (tip-tobase orientation), ventral side facing the top of the page. Scale bar (Fig. 30) represents 100 nm. Fig. 30. Proximal section. Triplet microtubules are present in basal body 2, which is connected to basal body 1 by the deltoid striated band (DSB). The proximal ends of roots R1, R2 and R4 are visible. Fig. 31. Distal section. Doublet microtubules are present in the basal body. Roots R1 and R2 diverge at a small angle from the basal body. Figs 32-35. Cross-sections of basal body 1, from a series, viewed from the anterior end of the cell (baseto-tip orientation), ventral side facing the top of the page. Scale bar (Fig. 32) represents 100 nm. Fig. 32. Proximal section. Triplet microtubules are present. Dark material on the left side of the basal body represents the attachment point of the deltoid striated band. Fig. 33. The proximal end of root R4 is associated with dark material on the left side of the basal body. Fig. 34. Triplet microtubules appear in the basal body only in the dark material on the nuclear envelope (asterisk) and near root R4. Other microtubules are doublets. Fig. 35. Distal section, near the transition zone of the basal body. Doublet microtubules are present. Root R4 diverges at a small angle from the basal body (see also Fig. 38). Fig. 36. Orientation as for Figs 30, 31. The proximal end of root R1 (asterisk) is associated with dark material on the right side of basal body 2. Scale bar represents 100 nm. Fig. 37. Secondary cytoskeletal microtubules (arrows) associated with root R1. Scale bar represents 250 nm. Fig. 38. Root R4 has two microtubules and diverges at a small angle from basal body 1. Scale bar represents 250 nm. Fig. 39. A fine fibril (arrow) extends between the proximal end of two-stranded root R4 and basal body 1. Scale bar represents 100 nm. Fig. 40. Light micrograph of amoeboid cell with pseudopods (arrows). Scale bar represents 2 µm. Figs 41-43. Electron micrographs of amoeboid cells. Fig. 41. Whole-mount micrograph of cell with both flagellum and pseudopods. Scale bar represents 1 µm. Fig. 42. Section of amoeboid cell with dehisced flagella. The angle between centrioles (B) is not yet the acute angle seen in vegetative cells. The transition zones of the centrioles are at the plane of the plasmalemma (visible in only one of the two in this image). Pseudopods are very fine and without apparent structure (arrows). Scale bar represents 500 nm. Fig. 43. Whole-mount micrograph of settling vegetative cell (lorica-building phase?) surrounded by short pseudopods. Scale bar represents 1 µm.
Source publication
Lagynion delicatulum Skuja is a first record for New Zealand freshwaters. Individual vegetative cells in nature and culture were sessile, aflagellate, and surrounded by a hyaline lorica lacking mineral deposits. Cells were uninucleate, had one or two chloroplasts with girdle lamellae and ring nucleoids, several mitochondria, and two to four basal-b...
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... microtubular roots, R1 and R2, were associated with the anterior basal body. Root R1 originated adjacent to a pad of electron-dense material on the right ventral side of the basal body at its proximal end (Fig. 36). It then passed dorsally along the right side of the cell just underneath the plasmalemma (Figs 30, 31) and terminated at the dorsal surface. The root was two-stranded through- out its length, and it bore secondary cytoskeletal micro- tubules, some of which originated near the basal bodies and extended posteriorly beyond them ( Figs ...
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Citations
... While the addition of layers to the inner surface of loricae has been shown previously for example in the chlorarachniophyte species Lotharella vacuolata [37], L. globosa [38] and L. reticulosa [39], the growth of loricae has not. This expansion is unique for loricae, which are usually more or less opened to one side, retain a constant size after formation and are found in distantly related eukaryotic groups such as Dinobryon (Ochrophyta) [40], Strombomonas (Euglenophyta) [41] and choanoflagellates [42]). Whether loricae of G. wildpretii retain one or more ostiole(s) at all times is not known. ...
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