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Sunday Protist - Lagynion: bottled algae

Quick one today as I should really be writing a chapter, as well as the post on plastid thiefs some of you wanted. And haptophytes. Have I mentioned my ADD tendencies?

While I find ochrophytes (large group including diatoms and kelps) a bit too phycological for my tastes, some of them are actually really cool, especially Chrysophytes - the 'golden algae'. Chrysos include things like scaly flagellates (Paraphysomonas) and Dinobryon which makes colonies that look like trees of stacked wine glasses. A while ago we had bottled ciliates, and this time the Chrysophytes offer us a few bottled algae, especially the flask-shaped Lagynion.

A happy(?) clump of photosynthetic flasks, of Lagynion. Source: Micro*scope.

The lorica consists of organic material. The progeny following division are released as little zoospores bearing the ridiculously complicated flagella characteristic of ochrophytes (one of them too short to be easily visible). Then the zoospores settle down, become amoeboid and grow themselves a new flask. As far as I could gather, that's pretty much all there is to say about Lagynion at the moment. But it still looks pretty cool!

1. Side view. Arrowheads indicated a rib structure surrounding the 'flask'. 2 and 3: top views of three Lagynion cells showing optical sections through the base and the neck regions, respectively. 4. TEM of 'flask'. Note the plastids (C) and the nucleus (N). V - peripheral vesicles. In short, plastids in a bottle. (O'Kelly & Wujek 2001 Eur J Protistol)

In fact, there's a whole family of bottled, and often amoeboid, algae called Stylococcaceae (eg. see Nicholls 1987 J Phycol), but they are so obscure it's painful to find much literature on them, or even decent pictures. Especially since by the time they get digitised, a lot of the old images become completely illegible. But here's another member of the family bearing slightly different glassware, Chrysopyxis:

Source: Micro*scope

Now to do real work and then write up some of the really exciting stuff I came across lately. And crush my writer's block with something sharp and heavy. Really annoying when you can't write anything because, well, you can't write anything. Wish brains came with instruction manuals...

References
Nicholls, K. (1987). CHRYSOAMPHIPYXIS GEN. NOVA A NEW GENUS IN THE STYLOCOCCACEAE (CHRYSOPHYCEAE) Journal of Phycology, 23 (3), 499-501 DOI: 10.1111/j.1529-8817.1987.tb02537.x

O'Kelly, C., & Wujek, D. (2001). Cell structure and asexual reproduction in Lagynion delicatulum (Stylococcaceae, Chrysophyceae) European Journal of Phycology, 36 (1), 51-59 DOI: 10.1080/09670260110001735198

PS: Hardly relevant but kind of newsworthy: First Phaeophyte genome sequenced! (Cock et al. 2010 Nature) Until now, the only complete Stramenopile(=Heterokont) genomes were a couple diatoms and oomycetes. Ok, there's still many more to go but Phaeophytes can be interesting in terms of studying the evolution of multicellularity. Also, the ochrophyte clade is a phylogenetic mess; not that single whole genome data means much but could perhaps helps calm the harsh seas somewhat.

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