Microworld

world of amoeboid organisms

Menu
Vannella lata
Clydonella sawyeri, from Kudryavtsev and Volkova 2018

 

Genus Clydonella Sawyer, 1975

Diagnosis: Characters of the genus are intermediate between Vannella and Platyamoeba. Locomotive form with anterior hyaline region occupying 2/3 of the cell length. Hyaloplasm with faint lateral folds as ripples over anterior region. Locomotive form ovoid, usually 10 to 40 µm. No posterior uroid. Floating form with radiate, sometimes irregularly twisted pseudopodia; in some, radiating pseudopodia bent or extended in multiples of 2. Nucleus distinct with central nucleolus. Cytoplasm containing few vesicles. No cytoplasmic crystals or cysts. Fine structure of cell coat unknown.

Ecology: All 5 species marine.

C. vivax Schaeffer 1926
C. rosenfieldi Sawyer 1975
C. sindermanni Sawyer 1975
C. wardi Sawyer 1975
C. vivax, from Bovee and Sawyer, 1979
C. sawyeri Kudryavtsev and Volkova, 2018

 

Clydonella sawyeri  Kudryavtsev and Volkova, 2018

Diagnosis. Locomotive forms 6.9-16.6 μm (average 10.6 μm) long, 5.9-20 μm (average 13.8 μm) broad, length:breadth ratio 0.49-1.28 (average 0.79) (n=107); in majority of cells breadth is greater than length. Rounded, oval or arc-shaped during locomotion, frequently with concave posterior margin, seldom with extended, triangular posterior end (that mostly occurs when changing the direction of movement). Floating form irregularly rounded, without pseudopodia. Ovoid vesicular nucleus 2.6-5.3 μm in diameter (average 3.7 μm) with large central nucleolus 1.6-2.9 μm in diameter (average 2.2 μm) (n=78). Glycocalyx consisting of fibrous basal layer, vertical pentagonal glycostyles ca. 100 nm in length, and simple filaments about 200 nm long.

Type locality: littoral zone of Seldyanaya Bay, Chupa Inlet (Kandalaksha Bay, The White Sea, North-Western Russia; 66.3384387N, 33,618127E), upper layer of mud and sand, salinity 22‰;

Reference: Kudryavtsev, A., Volkova, E., 2018. Clydonella sawyeri n.sp.(Amoebozoa, Vannellida): Morphological and molecular study and a redefinition of the genus Clydonella Sawyer, 1975. European Journal of Protistology https://doi.org/10.1016/j.ejop.2018.01.008

 

Clydonella sindermanni
Clydonella sindermanni, from Bovee and Sawyer, 1979
Clydonella vivax

 

Recent posts

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

Velamentofex tyrolensis (photomicrograph Steffen Clauß) Family Velamentofexidae Völcker and Clauß, 2020 Diagnosis: Multinucleate organic-walled monothalamous foraminifera. Test spherical to pyriform, usually surrounded by a broad

Read More »

Claparedellus lachmannii

Claparedellus lachmannii, common shape (Riedensee) Claparedellus lachmannii  Khanipour Roshan and Clauß, 2020 Diagnosis: Multinucleate organic-walled monothalamous foraminifera. Test spherical to elongated pyriform or irregularly shaped, with a

Read More »

Claparedellus

Claparedellus lachmannii Genus Claparedellus Khanipour Roshan and Clauß, 2020 Diagnosis: Multinucleate organic-walled monothalamous foraminifera. Test spherical to elongated pyriform or irregularly shaped, with a hyaline, flexible,

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 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 »