Heleopera ()
Description
Heleopera is a genus of
testate amoebae, a type of
unicellular amoeboid that are enclosed in a shell known as the test. In particular, it belongs to the order
Arcellinida, which includes testate amoebae with
lobosa (round, blunt-ended)
.
The genus is characterized by an ovoid, laterally compressed test composed of a cancellated chitinoid membrane with a reticulate appearance of mostly dotted lines, often incorporating particles of sand. The test opening, or 'mouth', is large, elliptical and has a terminal position. Through this opening, the organism extends numerous digitiform pseudopods.
The conspicuous slit-like (laterally compressed) terminal opening found in this genus is what distinguishes the infraorder Volnustoma from other groups of Arcellinida. In addition, the tests are reinforced with mineral particles.
Systematics
Taxonomy
The
genus Heleopera was described by American paleontologist
Joseph Leidy in his 1879 book
Fresh-water rhizopods of North America. He constructed the generic name from the
Greek language words
helos, meaning
bog, in reference to
, its frequent habitat; and
pera, meaning
bag, in reference to the shape of its test. He transferred the species
Nebela sphagni to this new genus and assigned it as the
type species, but also changed the specific epithet to
picta, thus modifying its name to
Heleopera picta.
In the 1909 volume of
The British freshwater Rhizopoda and Heliozoa, British naturalist James Cash reinstated the epithet
sphagni,
arguing that the original epithet of a given species should be conserved if it is not preoccupied by an earlier name.
Consequently, the current accepted name of the type species is
Heleopera sphagni.
In 1942, a family was proposed to accommodate this genus, Heleoperidae.
Species
The genus includes 11 accepted species:
- = Difflugia lucida
- = Difflugia (Nebela) sphagni
- = Nebela sphagni
- = Heleopera picta
-
Heleopera steppica
-
Heleopera sylvatica
External links
