Microworld

world of amoeboid organisms

Menu

Actinosphaerium akamae (Shigenaka, Watanabe and Suzaki, 1980)

Diagnosis: Nuclei with nucleolar material as a central cluster of granules, and with a cyst wall not incorporating siliceous components.

Ecology: Fresh water.

Remarks: Much of the information provided about this species relates to the dimensions of the cell, and proportions of endoplasm and ectoplasm (morphometric characters). The proportions of endoplasm to ectoplasm (2-14:1) appear to have been calculated (rather than measured) using the minimum of one value against the maximum of the other. If the values are summed, they gives sizes for cells outside the range described in the paper. The cyst of A. akamae does not incorporate siliceous components, but is composed of several organic (i. e. mucous, granular, fibrillar and electron-dense ones) layers (Shigenaka et al. 1985). The appearance of nuclei is similar to that of A. eichhornii although they are reported as slightly smaller. In view of the discrepancies over reports of nuclear size in A. eichhornii and in view of the variability of this character, this aspect requires re-investigation. While there is little doubt that different stocks investigated by the Japanese workers exhibited consistent and identifiable differences from which species, there are no absolute characters by which A. akamae can be identified except the absence of siliceous elements from the cyst. Given the overall similarity of this taxon to A. eichhornii, the uncertainty over some of the distinguishing characters, we treat the taxon as nomen dubium until the unusual nature of the cyst is confirmed and/or other discriminatory characters emerge (all remarks from Mikrjukov and Patterson, 2001).

Recent posts

Arcella guadarramensis

A. guadarramensis – after González-Miguéns et al., 2021 Arcella guadarramensis González-Miguéns & Lara, 2021 Diagnosis: Color ranges from transparent to yellow-orange. Sub hemispherical test shape, with flattened

Read More »

Galeripora

G. naiadis – after González-Miguéns et al., 2021 Genus Galeripora González-Miguéns, Soler-Zamora, Villar-dePablo, Todorov & Lara, 2021 Diagnosis: Tests built exclusively with proteinaceous organic material. Shape more

Read More »

Galeripora naiadis

G. naiadis – after González-Miguéns et al., 2021 Galeripora naiadis González-Miguéns, Soler-Zamora, Villar-dePablo, Todorov & Lara, 2021 Diagnosis: Color ranges from transparent to yellow-orange. The test has

Read More »

Galeripora balari

G. balari – after González-Miguéns et al., 2021 Galeripora balari González-Miguéns & Lara, 2021 Diagnosis: Color ranges from transparent to yellow-orange. General test shape is rounded and

Read More »

Galeripora sitiens

G. sitiens – after González-Miguéns et al., 2021 Galeripora sitiens González-Miguéns, Soler-Zamora, Villar-dePablo, Todorov & Lara, 2021 Diagnosis: Color ranges from transparent to yellow-orange. General test shape

Read More »

Galeripora bufonipellita

G. bufonipellita – after González-Miguéns et al., 2021 Galeripora bufonipellita González-Miguéns & Lara, 2021 Diagnosis: Color ranges from transparent to yellow-orange. General test shape is rounded and

Read More »

Galeripora succelli

G. succelli – after González-Miguéns et al., 2021 Galeripora succelli González-Miguéns & Lara, 2021 Diagnosis: Colour ranges from transparent to yellow-orange. Sub hemispherical test shape, with flattened

Read More »

Galeripora galeriformis

G. galeriformis – after González-Miguéns et al., 2021 Galeripora galeriformis González-Miguéns, Soler-Zamora, Villar-dePablo, Todorov & Lara, 2021 Diagnosis: Colour ranges from transparent to yellow-orange. General test shape

Read More »

Difflugia globulosa – Ogden

Difflugia globulosa, Crailoo, Netherlands, 2021 Difflugia globulosa (Dujardin, 1837) sensu Ogden, 1988 Diagnosis: Shell light to dark brown, spherical, composed of small and large quartz

Read More »

Leptomyxa spec.

Leptomyxa sp. Leptomyxa sp. Diagnose: Slowly moving amoeba with a long tubular body with some lobopodia at both ends extending in several directions and also

Read More »