Peritrichs are a subclass of ciliates that are usually bell
or disc shaped and have a prominent paroral membrane starting in the oral
cavity and circling around the anterior of the cell in a counter clockwise
direction. Pseudovorticella is a
genus within this subclass that was established to differentiate the organisms
within this genus from Vorticella, who have differently patterned
silverline system and have different oral infraciliature. This genus is rarely
investigated for a few reasons, firstly Pseudovorticella
has relatively few species compared to Vorticella
and receives little attention despite its wide distribution. Secondly the two
genus are very similar in vevo and the known species of Pseudovorticella are insufficiently described. Thirdly the two
genus are similar in living morphology, but the taxonomic ranking of many Vorticella can be doubted due to the
lack of silver staining data on them.
Sun et al. (2013)
sampled coastal areas of the Yellow Sea in Shandong, China, by placing an
artificial substrate and leaving it for 10 days to allow for colonisation. Once
collected the ciliates were isolated and identified. Five species from the
genus Pseudovorticella were isolated,
three of which were already known species (Pseudovorticella
plicata, P. banatica and P. anomala), and the two other species
were not thought to have been seen before, named Pseudovorticella dingi and P.
wangi. They then go on to describe the two newly discovered species in
great detail and giving comparisons of other similar species. With the three
already known species thy simply add more detail to the already known
information.
This paper is a simple identification paper, they do not
talk about or hazard a guess as to any possible niches the new or old species
may fulfil. This paper simply contributes to the known biodiversity of the
ciliates and adds more detail to help the taxonomic ranking of the current
known species.
Merry Christmas
Referenced paper:
Sun P., Ma H., Shin M.K. and
Al-Rasheid K.A., (2013). Morphology of two new marine peritrich ciliates from
Yellow Sea, Pseudovorticella dingi nov. spec. and P. wangi nov. spec., with
supplementary descriptions of P. plicata, P. banatica and P. anomala
(Ciliophora, Peritrichia). European journal of protistology. 49(3).
pp.467-476.
Hi Evan,
ReplyDeleteThank you for your wonderful Christmas gift. If I may reciprocate, you noted at the end of post that the biogeochemical/ecological role of peritrichs was lacking from this paper. Exciting work done by Monika Bright (of vent tube worm fame) has identified the presence of ectosymbiotic sulfur oxidising bacteria are present in the shallow-water peritrich Zoothamnium niveum (in the same family as Vorticella and kin) (Rinke et al, 2003). In another study, the presence of sessile ciliates on the egg capsules of marine gastropod larvae was found to significantly reduce intracapsular PO2 and could have a pronounced effect on larval development (Cancino, et al 2000). Peritrichs can have a major effect on small-scale biogeochemistry in shallow water environments, and therefore any new species discovered could play exciting new roles in ocean processes.
Thanks again and Merry Xmas,
Davis
Rinke, C., Schmitz-Esser, S., Stoecker, K., Nussbaumer, A. D., Molnár, D. A., Vanura, K., ... & Bright, M. (2006). “Candidatus Thiobios zoothamnicoli,” an ectosymbiotic bacterium covering the giant marine ciliate Zoothamnium niveum. Applied and environmental microbiology, 72(3), 2014-2021. http://aem.asm.org/content/72/3/2014.short
Cancino, J., Gallardo, J., & Torres, F. (2003). Combined effects of dissolved oxygen concentration and water temperature on embryonic development and larval shell secretion in the marine snail Chorus giganteus (Gastropoda: Muricidae). Marine Biology, 142(1), 133-139. http://link.springer.com/article/10.1007/s00227-002-0925-3
Thanks for the extra reading Davis,
DeleteI have also found a paper by Sergeeva & Dovgal (2014) in which they have found peritichs living on copepods under hypoxic/anoxic conditions, this paper has then been cited six times since it has been published.
-Evan
Sergeeva N. and Dovgal I., (2014). First finding of epibiont peritrich and suctorian ciliates (Ciliophora) on oligochaetes and harpacticoid copepods from the deep-water hypoxic/anoxic conditions of the Black Sea. Ecologica Montenegrina. 1(1). pp.49-54.