world of amoeboid organisms

Choanocystis pertusa
From Siemensma, 1991

Choanocystis pertusa (Dürrschmidt, 1987) Siemensma, 1991

Diagnosis: Periplast, 50-60 µm in diameter (measurement based on whole mount), with two types of scales; details of protoplast unknown. Spine scales, 15-25 µm long, consisting of shaft and base-plate. Shaft, 0.2 µm thick, apparently solid or only partly hollow. Spines slightly tapering towards the distal end, apex with 4 margi­nal teeth. Shaft seated eccentrically to a heart-shaped base-plate, 1.4 µm in diameter. Plate scales, 5.6-6 x 3.3 µm, elliptical, sometimes slightly curved. Scale ornamenta­tion consists of n µmerous radial slits, 0.56 µm long and 0.07-0.14  µm wide, directly situated on both sides of the axial thickening, which is 3.0  µm long. Rest of the scale smooth.

Remarks: It is not possible to distinguish between C. granulata and C. pertusa with reference to the spine scales alone, though these of C. pertusa are 1/4 longer than those of C. granulata. The slit-pattern on the otherwise smooth plate scales, is the most characteristic feature of C. pertusa and plate scales are about twice as large as those of C. granulata.

Distribution: Sri Lanka.

Recent posts

Penardochlamys arcelloides

P. arcelloides – after Penard, 1904 Penardochlamys arcelloides  (Penard, 1904) Deflandre, 1953 Diagnosis: Colorless or very slightly yellowish envelope, bag or cauldron-shaped, very thin, chitinous,

Read More »

Reticulomyxa hannae

R. hannae, plasmodium – photomicrograph Steffen Clauss Reticulomyxa hannae Völcker and Clauß, 2020 Diagnosis: Trophozoites surrounded by a very thin mucous envelope, with slowly moving plasmodia, variable

Read More »

Velamentofex saxonensis

V. saxonensis, feeding (photomicrograph Steffen Clauss) Velamentofex saxonensis Völcker and Clauß, 2020 Diagnosis: Trophozoites ovoid, 30-95 μm, granuloreticulopodia up to 1000 μm long. with a hyaline, thin

Read More »

Velamentofex tyrolensis

V. tyrolensis (photomicrograph Steffen Clauss) Velamentofex tyrolensis Völcker and Clauß, 2020 Diagnosis: Trophozoites ovoid, 98-125 μm, with reticulopodia up to 300 μm long, with a hyaline,

Read More »

Velamentofex berolinensis

V. berolinensis Velamentofex berolinensis Völcker and Clauß, 2020 Diagnosis: Trophozoites ovoid, 50-300 µm, with a hyaline, extremely flexible, membranous test. Nuclei numerous, 11.6-16.2 µm in diameter,

Read More »


 Lieberkuehniidae  Siemensma, Holzmann, Apothéloz-Perret-Gentil, Clauß, Voelcker, Bettighofer, Khanipour Roshan, Walden, Dumack and Pawlowski, 2020 Diagnosis: Multinucleate organic-walled monothalamous foraminifera. Test very flexible, elongated to broadly

Read More »