In case you’re running out of reading material on the testate amoeba family Arcellidae, here’s a link to the preprint of our new paper: https://www.biorxiv.org/content/10.64898/2026.08.19.745684v1.full We update many aspects of this interesting group, but if I had to choose a headline I guess it would be this: Joseph Leidy–the last man who knew everything–was right…
Amoebae in the family Arcellidae make their shells from a self-produced organic substance, without incorporating any other building materials (diatoms, hard scales, bits of quartz etc.). Although described in older sources as “chitinous,” and in newer ones as “keratin-like”, the precise composition of this substance is still unknown. The stuff is not laid down as…
A couple of blog posts ago, I discussed some recent research suggesting that some testate amoebae use their shells for predation. Yesterday, I was looking at samples from Mer Bleue Bog, and came across some more specimens of the handsome amoeba I mentioned in that post, Netzelia corona. I took some time to look more…
A shelled amoeba I discovered nearly eleven years ago finally has a name! Meet Arcella prismatica Taylor, Strueder-Kypke & Siemensma, 2025. So far, this pretty morphotype has only been found at two sites, a brown-water lake in Ottawa’s Mer Bleue Bog, and a roadside mire in the Cree Nation of Chisasibi, on the Quebec coast…
Netzelia corona is a testate amoeba with “teeth” around the aperture of its shell. It also has some impressive spines jutting out from its posterior, which have obvious advantages as a defensive apparatus. But it’s the teeth that have always puzzled me. They’re very neatly made, featuring uniform lobes of organic cement from which tiny,…
Two wrongs don’t make a right. Fifty wrongs, however, can make a scientific consensus. All it takes is a large enough number of researchers drawing similar conclusions from a big enough pile of bad data. A confirmation cycle sets in, and tentative suggestions begin to solidify into confident assertions. A weird idea that might be…
