Chlamydaster laciniatus

(Penard, 1904) Rainer, 1968

Most likely ID: n.a.

 

Synonym: n. a.

 

Sampling location: Simmelried

 

Phylogenetic tree: n.a.

 

Diagnosis: 

  • body spherical, surrounded by mucus sheath
  • diameter 15–30 µm
  • mucus sheath covered by delicate, straight spicules (needles) forming X-shaped figures
  • 2–3 contractile vacuoles near surface
  • spherical nucleus with nucleolus, located eccentrically
  • cytoplasm contains often green, yellow, or brown granules
  • numerous axopodia with granules, up to 45–50 µm long
Chlamydaster-laciniatus
Chlamydaster laciniatus

I find Chlamydaster laciniatus regularly in the Simmelried, but never frequently. The species can be recognized by the spicules, which cover the outer mucus layer and produce a typical X-pattern (s. figs. 1 a-c and 2). Only at high magnification one can recognize the single needle-shaped spicules, which are 6–7 µm long according to my measurements (s. fig. 3). There should be 2–3 contractile vacuoles, but I could also observe specimens with 4 contractile vacuoles. All specimens in my population had a very constant diameter of 20–22 µm. I have never found larger specimens. The axopodia in an undisturbed specimen are covered with granules at more or less regular intervals (s. fig. 4). The maximum length of the axopodia in my population was about 50 µm.

 

More images and information on Chlamydaster laciniatus: Ferry Siemensma-Microworld-Chlamydaster laciniatus

Chlamydaster-laciniatus

Fig. 1 a-c: Chlamydaster laciniatus. D = 21 µm. Three focal planes of a slightly squashed specimen. Obj. 100 X.

Chlamydaster-laciniatus

Fig. 2: Chlamydaster laciniatus. A strongly squashed specimen. CP = centroplast, CV 1-3 = contractile vacuoles, Nu = nucleus with a central nucleolus. Obj. 100 X.

Chlamydaster-laciniatus

Fig. 3: Chlamydaster laciniatus. D = 21 µm. A starving specimen free from food vacuoles. The needle-shaped spicules (SP) covering the mucus sheath are 6–7 µm long. AX = axopodia, Nu = nucleus. Obj. 100 X.

Chlamydaster-laciniatus

Fig. 4: Chlamydaster laciniatus. D = 20 µm. A fully extended specimen. The longest axopodium of the specimen has a length of 45 µm. Obj. 60 X.