Axodine
Encyclopedia
The axodines are a group of unicellular heterokont
algae.
They include pedinellids, silicoflagellate
s, and Rhizochromulinales.
Other terms include "Actinochrysophyceae" and "Dictyochophyceae".
single emergent flagellum, which lacks the root structure found in related groups, and is extended into a wing-like form supported by an internal rod. They also have tentacles or axopods supported by triads of microtubule
s, arising from the surface of the nucleus
.
s, marine plankton that form siliceous skeletons and are well-known as fossils.
is included here based on the structure of its zoospores. It is considered closer to the latter group than the former.
Heterokont
The heterokonts or stramenopiles are a major line of eukaryotes currently containing more than 100,000 known species. Most are algae, ranging from the giant multicellular kelp to the unicellular diatoms, which are a primary component of plankton...
algae.
They include pedinellids, silicoflagellate
Silicoflagellate
Dictyochales are a small group of unicellular heterokont algae, found in marine environments.-Characteristics:In one stage of their life cycle, they produce a siliceous skeleton, composed of a network of bars and spikes arranged to form an internal basket...
s, and Rhizochromulinales.
Other terms include "Actinochrysophyceae" and "Dictyochophyceae".
Characteristics
They characteristically have asingle emergent flagellum, which lacks the root structure found in related groups, and is extended into a wing-like form supported by an internal rod. They also have tentacles or axopods supported by triads of microtubule
Microtubule
Microtubules are a component of the cytoskeleton. These rope-like polymers of tubulin can grow as long as 25 micrometers and are highly dynamic. The outer diameter of microtubule is about 25 nm. Microtubules are important for maintaining cell structure, providing platforms for intracellular...
s, arising from the surface of the nucleus
Cell nucleus
In cell biology, the nucleus is a membrane-enclosed organelle found in eukaryotic cells. It contains most of the cell's genetic material, organized as multiple long linear DNA molecules in complex with a large variety of proteins, such as histones, to form chromosomes. The genes within these...
.
Order Dictyochales
The most notable group is the silicoflagellateSilicoflagellate
Dictyochales are a small group of unicellular heterokont algae, found in marine environments.-Characteristics:In one stage of their life cycle, they produce a siliceous skeleton, composed of a network of bars and spikes arranged to form an internal basket...
s, marine plankton that form siliceous skeletons and are well-known as fossils.
Order Pedinellales
Most other axodines form a group variously called the pedinellids or actinodines.Order Rhizochromulinales
In addition to the silicoflagellates and actinodines, the marine amoeboid Rhizochromulina marinaRhizochromulina
Rhizochromulina is an unusual genus of marine heterokont algae, with one species, R. marina. They are colored amoeboids with a single flagellum, and produce distinctive spindle-shaped zoospores. These have a cell structure typical of the axodines...
is included here based on the structure of its zoospores. It is considered closer to the latter group than the former.