Protozoa Guide review

Pteridomonas

genus / PEDINELLALES

Description

Cells very similar to Actinomonas, but tentacles are mainly confined to an anterior ring around the flagellum, and the cells are usually attached to a substratum . They also differ in the presence of a very reduced flagellar wing and paraxone- mal rod and in the presence of 2 ring -I ike structures below the transverse septum of the flagellar transition region (Patterson and Fenchel 1985). Such rings are also present in Apedinella but not in any other pedinellid. H et- erotrophic, feeding on bacteria and on other protists . Three species in marine, freshwater , and brackish environments. Pteridomonas danica Patterson and Fenchel (Figs. 4A-D,8C) . Cells 3.5-5.5 1--lm in diameter. Attached with a narrow contractile stalk of variable length, mostly 15-25 long. With c. 1 2 tentacles around the flagellum base. Cells may detach from the substrate and swim freely, often with the tentacles resorbed and occasionally with the stalk resorbed . Cells caught in debris may deform and move by amoeboid locomotions (Patterson and Fenchel 1985). Common but of- ten confused with Actinomonas. 782 SILICOFLAGELLA

Type species

Figures

Figure 4
Fig. 4
Pteridomonas danica . A. Cell with food

Raw text

Cells very similar to Actinomonas, but tentacles
are mainly confined to an anterior ring around
the flagellum, and the cells are usually attached
to a substratum . They also differ in the presence
of a very reduced flagellar wing and paraxone-
mal rod and in the presence of 2 ring -I ike
structures below the transverse septum of the
flagellar transition region (Patterson and
Fenchel 1985). Such rings are also present in
Apedinella but not in any other pedinellid. H et-
erotrophic, feeding on bacteria and on other
protists . Three species in marine, freshwater ,
and brackish environments.
Pteridomonas danica Patterson and Fenchel
(Figs. 4A-D,8C) . Cells 3.5-5.5 1--lm in diameter.
Attached with a narrow contractile stalk of
variable length, mostly 15-25 long. With c. 1 2
tentacles around the flagellum base. Cells may
detach from the substrate and swim freely, often
with the tentacles resorbed and occasionally
with the stalk resorbed . Cells caught in debris
may deform and move by amoeboid locomotions
(Patterson and Fenchel 1985). Common but of-
ten confused with Actinomonas.
782 SILICOFLAGELLA