Thanks, Genoveva! I think I can do better, though. When I got home and reviewed the day's pictures, I realized I'd had the spot size set much too high.

😆 The ones in this subarctic population seem to deliberately choose the biggest and longest xenosomes they can find. It's as if they want to make themselves big, for some reason.

@tedersoo.bsky.social Thanks for an excellent overview of the subject...especially the lists of "benefits" and "shortcomings/risks", and the suggested amendments to codes.

I'm delighted by the idea of amoebae jetting around like squids. 😁 Sadly, it doesn't happen. Like other arcellinids (many of which also have spines on their shells) they crawl along the substrate with their pseudopods, which only protrude through the aperture and never through the "horns".

Nope, still haven't run into Legendrea! But I've mostly been poking around in submerged Scorpion-moss and Sphagnum.

I picked out as many as I could, in the time I had, and should have enough to sequence & measure. 😀 I kept the original jars, too, but after two days in the car I don't expect to see many more live ones.

Home again, now, with my boreal bog plunder!

Mine are for holding my glasses in place. So..secondary organs of sight, essentially. 😉

The quartz shards are embedded in some kind of organic cement, the exact makeup of which is not known (likely polysaccharides and proteins).

Oh, sorry. 😄 The shells are air-dried on carbon adhesive tabs mounted on SEM stubs, then sputtered with gold/palladium and put right in the machine.

Scanning electron microscope 🙂

Interestingly, organic cement in my populations of D. leidyi is similar to that of D. bacillariarum...but different from the cement of D. elegans shown in Todorov & Bankov. Meanwhile, D. bacillariarum has long been suspected of being identical to D. elegans. The taxonomy is "under construction". 😄

The Todorov & Bankov "atlas" is nice. It includes morphometric tables...very handy! D. leidyi was synonymized w/ D. elegans by Mazei & Warren in 2012. I'm skeptical, too, but shd add that consistently distinct phenotypes can be molecularly identical (see Hyalosphenia papilio paynei).

My copy of Leidy needs a new binding too. Customs agents slashed the spine with boxcutter while checking to see what kind of contraband I might be importing. The nearest modern equivalent to Cash, Wailes & Hopkinson, or Penard, is Ferry Siemensma's fabulous website!

Also...that's a really nice picture!

Yup, Difflugia leidyi...named for Joseph Leidy, who found a single specimen of the morphotype, which he didn't give a name. He was careful, that way, reluctant to create new taxa. :)