Paludicella articulata (Ehrenberg 1831)

Verder in Nederlands
Nederlands

  1. More information
  2. Photos
  3. Microscope photos and videos
  4. Hybernacula

Proposal for common name: Segmented bryozoan or moss animal

Paludicella articulata

Classification

Class Family Genus Species First described by
Gymnolaemata Ctenostomata Paludicella P. articulata Ehrenberg 1831

Synonyms

The following synonyms have been used to indicate P. articulata:

  1. Alcyonella articulara (Ehrenberg 1831)
  2. Alcyonella diaphana (Nordmann 1832)
  3. Paludicella articulata (Gervais 1836)
  4. Paludicella ehrenbergi (Van Beneden 1848)
  5. Paludicella elongata (Hanckock 1850)
  6. Paludicella elongata (Leidy 1851)

Description

Also see the generic class and genus description in the classification page.
A combination of literature has been used to create this description.

General
  1. Zooids thin as hairs
  2. Colony strongly branching
  3. Colony grows partly against the substrate an partly as free standing or hanging branches.
  4. Cystid spindle shaped
  5. The lopophore extends from the polypide through a sideways square extension.
  6. Cystids are never adherent
  7. Cystid always separated by septs.
  8. Cystid wall partly covered with chalk particles.
  9. Colonies have a more delicate appearance than Fredericella and Plumatella species. They are more regularly branching.
  10. Zooids have no epistome.
Color Brownish, yellow-brown
Tentacle crown Tentacle crown round with 10 to 20 tentakles.
Size One zooid is 250-450 Ám long
A colony 10 cm in diameter maximum
Statoblasts No statoblasts
P. articulata forms hybernacula (that remain when the colonie dies) that are brown and very irregular in shape
Conditions In clean water to 20 meter depth
Below stones or wood
Distribution No information found in literature
Additional P. articulata is the most thin of the branching species.
A new zooid develops by distal (of the original 'mother' zooid away) budding that is separated from the originating zooid by a transverse wall (septum)

Relevant literature

To be completed

  1. [Mundy] - A key to the British and European Freshwater Bryozoans
  2. [Wood II] - A new key to the freshwater bryozoans of Britain, Ireland and Continental Europe

My observations

  1. P. articulata must be seen once to recognize, after that it is easy.
  2. It is easy to overlook the species or to assume they are a bushy algeal growth or so.
  3. I have found P. articulata (almost) never more shallow than 2 meters and never below 5 m.
  4. The colonies always grow on a place where they are sheltered from silt, such as below or beside stones or wood or even underneath a wreck of a rowing boat.
  5. The minimum depth of 2 meter is i assume derived from wave action.
    An alternative explanation may be intensive competition by algae and/or cyanobacteria.
  6. The maximum depth is possibly caused by the summer thermoclyne, below which the oxygen and possibly the food levels drop
  7. P. articulata often has a typical chitine shine also found on beetle shields.
  8. The brown color usually is light brown.
  9. In spring it is difficult to find P. articulata, as colonies are small and therefore easily overlooked. In summer and specially in the fall P. articulata is more easily found as colonies have grown bigger.
  10. Late fall, by the end of October as the water temperature has declined to about 9║ Celsius colonies die.
  11. In spring P. articulata is the first species to start growing, when the water temperature rises above about 10║ Celsius
  12. Part of a bigger (summer or fall) colony is often partly dead or covered in silt that makes it difficult to spot them.