Protozoa Guide review

Dictyocha,

genus / DICTYOCHALES / , for which the oldest name appears to be

Description

The extant species may all be referred to this genus. Only three species are well known . They have been classified into three different genera, but this appears to be unwarranted . For dis t r i - bution of the species in the seas in relation to temperature and salinity, see Henriksen et al. (1993) . Dictyocha speculum Ehrenberg, 1837. The skeleton comprises two well-separated rings , interconnected by six bars . The outer ring hex- agonal, the inner almost circular Six spines ex- tend in a radial direction from the outer ring, two opposite spines usually slightly longer than the others. The cell is located in a cavity formed by the rings. The diameter of the outer ring is c. 20 1-1m and in Danish material the distance be- tween the tips of the longest spines was 37.5-56 1-1m (Moestrup and Thomsen, 1 9 9 0). The naked stage is more or less spherical , 778 SILICOFLAGEL 15-20 ).lm in diameter, occasionally smaller (to 10 ).lm in culture) , the front end slightly flat- tened with a distinct pit . Flagellum 20-30 ).lm long. Cells contain 30-50 chloroplasts. The multinucleate stage with numerous. organelles; of all types, more or less spherical , 4 5-5 0 0 ).lm in diameter. Widely distributed in cold and temperate seas, at temperatures up to 18-20 °C (Henriksen et al., 1993). G oneme of flagellum ; B, paraxonemal rod supporting the flagellar wing ; C, chloroplast ; F, flagellum ; G, Golgi body; IPE, OPE, chloroplast envelope; MT, i m- mature flagellar hairs , MTT, microtubules ; N, nu - cleus; NE, nuclear envelope ; Pu , pusule-like cav ity ; S, plate scales ; SS, spine scales; V, vacuole . Not to scale . (From Throndsen , 1971 ). LATA vacuole. B, Details of cell structure. C. Tentacle with triplet of microtubules. D. Cell division . Ab- breviations in Fig . 48 : A, tentacle ; B, endosymbi- otic bacteria ; CR, dense material on the nuclear envelope; CS, cytoskeletal elements; D, Golg i body; DB, dense bodies; DV, digestion vesicles ; E, extrusomes; Kl , K2 , basal bodies; L, lipid ; M, mi- tochondrion ; MS , tripartite flagellar hairs ; N, nu- cleus; R, paraxonemal rod ; TZ , flagellar transition zone; ST, stalk. Fig. 4A=18,000x. (After Patterson and Fenchel, 1985).

Type species

Figures

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Raw text

The extant species may all be referred to this
genus. Only three species are well known . They
have been classified into three different genera,
but this appears to be unwarranted . For dis t r i -
bution of the species in the seas in relation to
temperature and salinity, see Henriksen et al.
(1993) .
Dictyocha speculum Ehrenberg, 1837. The
skeleton comprises two well-separated rings ,
interconnected by six bars . The outer ring hex-
agonal, the inner almost circular Six spines ex-
tend in a radial direction from the outer ring,
two opposite spines usually slightly longer than
the others. The cell is located in a cavity formed
by the rings. The diameter of the outer ring is c.
20 1-1m and in Danish material the distance be-
tween the tips of the longest spines was
37.5-56 1-1m (Moestrup and Thomsen, 1 9 9 0).
The naked stage is more or less spherical ,
778 SILICOFLAGEL
15-20 ).lm in diameter, occasionally smaller (to
10 ).lm in culture) , the front end slightly flat-
tened with a distinct pit . Flagellum 20-30 ).lm
long. Cells contain 30-50 chloroplasts. The
multinucleate stage with numerous. organelles;
of all types, more or less spherical , 4 5-5 0 0
).lm in diameter. Widely distributed in cold and
temperate seas, at temperatures up to 18-20 °C
(Henriksen et al., 1993).
G
oneme of flagellum ; B, paraxonemal rod supporting
the flagellar wing ; C, chloroplast ; F, flagellum ; G,
Golgi body; IPE, OPE, chloroplast envelope; MT, i m-
mature flagellar hairs , MTT, microtubules ; N, nu -
cleus; NE, nuclear envelope ; Pu , pusule-like cav ity ;
S, plate scales ; SS, spine scales; V, vacuole . Not to
scale . (From Throndsen , 1971 ).
LATA
vacuole. B, Details of cell structure. C. Tentacle
with triplet of microtubules. D. Cell division . Ab-
breviations in Fig . 48 : A, tentacle ; B, endosymbi-
otic bacteria ; CR, dense material on the nuclear
envelope; CS, cytoskeletal elements; D, Golg i
body; DB, dense bodies; DV, digestion vesicles ; E,
extrusomes; Kl , K2 , basal bodies; L, lipid ; M, mi-
tochondrion ; MS , tripartite flagellar hairs ; N, nu-
cleus; R, paraxonemal rod ; TZ , flagellar transition
zone; ST, stalk. Fig. 4A=18,000x. (After Patterson
and Fenchel, 1985).