Difflugia bacillariarum, 103 – 114 µm – Fochteloërveen, Netherlands

 

Difflugia bacillariarum Perty, 1849

Diagnosis: shell transparent, colorless or light yellow-brown, ovoid, spherical or pyriform usually with one or two prominent spines, usually pointed, of varying length, and positioned centrally, but it may be deflected to the side when the tapering is uneven; shell composed of thin siliceous plates overlaid by diatom frustules, which are united by an organic cement.

Dimensions: Length 57-103 µm (Ogden); 67-133 µm (Hoogenraad and De Groot, 1940).

Ecology: Sphagnum pools. Rare.

Remarks: It is thought that the basic shell is made of small shell plates and that the diatoms act as reinforcement. The organic cement is seen either as area of a patterned structure of small rings, or as strands between particles. The shape of the aperture is dependent on the arrangement and size of the diatoms which surround it. Small diatoms are usually used and the shape is circular, but it may vary to the extent of being triangular. Chardez (1978) observed that the aboral horn was either present or absent in specimens of D. australis (Playfair, 1918), a species that was initially described as a variety of D. bacillariarum. Although D. australis is alleged to differ from D. bacillariarum in size, the range of measurements given by Playfair (1918) for Australian species of both species are similar. Furthermore, Playfair noted that one specimen of D. bacillariarum australis was formed entirely of nebeloid plates, which supports the observation made above regarding the inner shell and diatom reinforcements.

   

Recent posts

Sphaerothecina

Infraorder Sphaerothecina Kosakyan et al., 2016   Diagnosis: Testate amoebae with a more or less spherical or semi-spherical test and a central aperture; test build

Read More »

Microcorycia bryophila

after Decloitre, 1974 Microcorycia bryophila Decloitre, 1974 Diagnosis: “This species bears a slight remembrance to Microcorycia tessellata Penard. The differences are as follows: With tessellata,

Read More »

Pseudodifflugia procera

Pseudodifflugia procera, after Badewitz, 2003 Pseudodifflugia procera Badewitz, 2003 Diagnosis: Test elongated cylindrical, remarkably slim, with straight or slightly curved flanks, in cross-section circular. Living

Read More »

Christinellula spec.

“Christinellula” “Christinellula“ from Spiegelplas Diagnosis: This specimen was present in a sample from the Spiegelplas (‘Mirror Lake’) in the Netherlands. It differs from previous observed

Read More »

Thecamoeba sp. 3

Thecamoeba sp. n = nucleus Thecamoeba sp. Diagnosis: Surface in locomotion with some longitudinal dorsal folds; outline in locomotion broadly oblong; hyaloplasm usually in a

Read More »

Schoenbornia humicola

Schoenbornia humicola – after Schönborn et al., 1987 Schoenbornia humicola (Schönborn, 1964) Diagnosis: Test small, not compressed, hyaline, with Nebela-like irregular siliceous plates and sometimes

Read More »