Search found 996 matches

by Bruce Taylor
Wed Sep 20, 2023 8:28 pm
Forum: Identification help
Topic: The Heliozoan Connection
Replies: 2
Views: 881

Re: The Heliozoan Connection

This is Clathrulina elegans . Biflagellate swarmer cells sometimes attach to mature organisms to form daisy-chain colonies, as in this rather cool image by Martin Kreutz: https://realmicrolife.com/wp-content/uploads/2023/09/Clathrulina-elegans-P7194341-Martin-Kreutz.jpg From: https://realmicrolife.c...
by Bruce Taylor
Mon Sep 18, 2023 4:15 pm
Forum: Identification help
Topic: New to me critter
Replies: 6
Views: 1412

Re: New to me critter

This is two stylonychine ciliates (probably Stylonychia) in conjugation. They are exchanging gametes. :)
by Bruce Taylor
Mon Sep 11, 2023 11:25 pm
Forum: Microscopes and optics
Topic: Removing the drawing attachment from Olympus BH2
Replies: 15
Views: 2263

Re: Removing the drawing attachment from Olympus BH2

Well, that worked perfectly. One quick puff with the bulb blower and all was clear.

Thanks for the help, everyone!
by Bruce Taylor
Fri Sep 08, 2023 5:21 pm
Forum: Microscopes and optics
Topic: Removing the drawing attachment from Olympus BH2
Replies: 15
Views: 2263

Re: Removing the drawing attachment from Olympus BH2

Thanks again, PeteM. I'll see if I can remove the debris with a bulb blower and/or soft brush, but if it comes to using solvents (even water!), I think I'll let them bring in the technician! :)
by Bruce Taylor
Fri Sep 08, 2023 2:18 pm
Forum: Microscopes and optics
Topic: Removing the drawing attachment from Olympus BH2
Replies: 15
Views: 2263

Re: Removing the drawing attachment from Olympus BH2

I was back at the museum yesterday, and set out to analyze the source of the dark spot in the light path. I brought a centering telescope, but it wasn't needed in the end because the problem was not subtle. ;) There's some loose debris inside the Nomarki/DIC intermediate tube, and a big piece is stu...
by Bruce Taylor
Sat Aug 19, 2023 11:41 am
Forum: Microscopes and optics
Topic: Removing the drawing attachment from Olympus BH2
Replies: 15
Views: 2263

Re: Removing the drawing attachment from Olympus BH2

Thanks for the advice, PeteM! I'll bring a centering telescope on my next visit (and an air-blower bulb).
by Bruce Taylor
Fri Aug 18, 2023 11:55 pm
Forum: Microscopes and optics
Topic: Removing the drawing attachment from Olympus BH2
Replies: 15
Views: 2263

Re: Removing the drawing attachment from Olympus BH2

Well, I managed to remove the drawing attachment. It did indeed have a spring-loaded plunger, as PeteM suggested (with a slot-headed screw in the end of the knurled knob). Knowing that "stuck oil" was probably the issue, I was a bit more forceful with the assembly, and pushed the dovetail against th...
by Bruce Taylor
Fri Aug 18, 2023 12:05 pm
Forum: Microscopes and optics
Topic: Removing the drawing attachment from Olympus BH2
Replies: 15
Views: 2263

Re: Removing the drawing attachment from Olympus BH2

Thanks deBult! That's all very useful information.

cheers,
Bruce
by Bruce Taylor
Thu Aug 17, 2023 5:04 pm
Forum: Microscopes and optics
Topic: Removing the drawing attachment from Olympus BH2
Replies: 15
Views: 2263

Re: Removing the drawing attachment from Olympus BH2

@Scarodactyl I tried the different settings on the drawing tube (A, B and C) but didn't see much difference in terms of light transmission. There's also a sort of rotating metal "hood" at the distal end of the tube, and when open it throws a distracting shaft of light over the middle of the visual f...
by Bruce Taylor
Thu Aug 17, 2023 4:22 pm
Forum: Microscopes and optics
Topic: Removing the drawing attachment from Olympus BH2
Replies: 15
Views: 2263

Re: Removing the drawing attachment from Olympus BH2

Thanks, PeteM. Next time I'm at the lab I'll give that a try. It seems quite possible that the screw oil is gunked up. That was certainly the case with the translation control knob on the prism slider, which required a LOT of persuasion, at first. I think this BH2 has received less love and attentio...
by Bruce Taylor
Thu Aug 17, 2023 2:52 pm
Forum: Microscopes and optics
Topic: Removing the drawing attachment from Olympus BH2
Replies: 15
Views: 2263

Removing the drawing attachment from Olympus BH2

At the museum lab where I sometimes look at ciliates there are two Olympus BH2 microscopes. One of them has a drawing attachment. The BH2 with the drawing attachment seems to be a bit less brightly illuminated than the other one, and consequently the images I make with it seem to be less clear. Is i...
by Bruce Taylor
Thu Aug 10, 2023 12:59 pm
Forum: Pictures and Videos
Topic: Heliozoa?
Replies: 2
Views: 386

Re: Heliozoa?

The term "Heliozoa" is a mess. Traditionally, the group incorporated organisms from many separate, unrelated lineages, united only by having a cell that looks vaguely like the sun. :D Some systems of classification retain a group called Heliozoa, but this is mostly restricted to a group called Centr...
by Bruce Taylor
Wed Aug 09, 2023 10:46 pm
Forum: Identification help
Topic: Unknown Euglena
Replies: 4
Views: 1302

Re: Unknown Euglena

A handy guide with color images, fairly up-to-date: Ciugulea, Ionel, and Richard E. Triemer. "A color atlas of photosynthetic euglenoids." (2010). In German, difficult to find and taxonomically out of date...but very comprehensive: Huber-Pestalozzi, Gottfried. "Das Phytoplankton des SuBwassers. 4. T...
by Bruce Taylor
Fri Aug 04, 2023 5:21 pm
Forum: Morphology and Behavior
Topic: Vorticella long stalks
Replies: 3
Views: 1563

Re: Vorticella long stalks

I believe Pseudovorticella have small blisters? Some species (such as P. monilata ) have conspicuous raised "tubercles", but others are quite smooth. All have an underlying pellicular pattern (the "silverline system") resembling brickwork, or a mesh; whereas, species of Vorticella have a silverline...
by Bruce Taylor
Thu Aug 03, 2023 1:23 pm
Forum: Morphology and Behavior
Topic: Vorticella long stalks
Replies: 3
Views: 1563

Re: Vorticella long stalks

In a revision of the genus from 1931, Noland & Finlay wrote: The length of the stalk has long been used as a specific trait. While it is true that the stalk length of various species does tend toward a modal value, the individual variation is too great to justify placing much taxonomic value on the ...
by Bruce Taylor
Sun Jul 30, 2023 10:17 pm
Forum: Identification help
Topic: A beautifully colored ciliate
Replies: 3
Views: 1089

Re: A beautifully colored ciliate

It has a long oral bulge, so is certainly not Enchelyodon or Holophrya , and is the wrong shape for Homalozoon . Apoamphileptus claparedii (= Amphileptus claparedii , often misspelled A. claparedei ) is a species with multiple contractile vacuoles, so that can be ruled out as well (the illustration ...
by Bruce Taylor
Thu Jul 27, 2023 11:15 pm
Forum: Identification help
Topic: Unknown Euglena
Replies: 4
Views: 1302

Re: Unknown Euglena

Euglena mutabilis. :)
by Bruce Taylor
Tue Jul 25, 2023 12:46 pm
Forum: Identification help
Topic: Unnumbered critters to identify
Replies: 2
Views: 832

Re: Unnumbered critters to identify

Tetrahymena is very likely (the shape and size are right, the mouth is in the right place, and they often congregate in large numbers, like this). However, identifying ciliates in dark field is difficult. Do you have bright field footage?
by Bruce Taylor
Mon Jul 17, 2023 10:20 pm
Forum: Identification help
Topic: Strange organism
Replies: 9
Views: 1860

Re: Strange organism

Actually....I've just watched the whole segment, and realize that I was too hasty. When I saw the video this morning, I only watched the first few seconds, before running out to the store. After watching the rest of the video, I think this is a different vampyrellid, Leptophrys vorax (previously kno...
by Bruce Taylor
Mon Jul 17, 2023 12:44 pm
Forum: Identification help
Topic: Strange organism
Replies: 9
Views: 1860

Re: Strange organism

It is Vampyrella, a cercozoan amoeboid that feeds on filamentous green algae. :)
by Bruce Taylor
Wed Jun 28, 2023 3:41 pm
Forum: Pictures and Videos
Topic: P. caudatum - DIC 40x, 60x, 60x slowmo
Replies: 8
Views: 1118

Re: P. caudatum - DIC 40x, 60x, 60x slowmo

josmann wrote:
Wed Jun 28, 2023 12:10 pm
Do the other P. caudatum morphotypes share the star shaped contractile vacuole? I did observe that in this specimen.
Yes, all members of the Paramecium Paramecium subgenus (at least nine morphospecies, apart from some recently identified cryptic species) have similar canal-fed CVs.
by Bruce Taylor
Wed Jun 28, 2023 11:29 am
Forum: Pictures and Videos
Topic: P. caudatum - DIC 40x, 60x, 60x slowmo
Replies: 8
Views: 1118

Re: P. caudatum - DIC 40x, 60x, 60x slowmo

Very nice microscopy! Oh I wanted to ask - what is the term for the lattice structure that makes up the cell membrane? The pellicle. I don't think you can identify this individual to species level. Paramecium identification can be surprisingly difficult, and can require careful inspection of micronu...
by Bruce Taylor
Tue Jun 27, 2023 12:32 pm
Forum: Identification help
Topic: What a wonder! A new unknown critter!
Replies: 8
Views: 1629

Re: What a wonder! A new unknown critter!

Oh, I'm sorry...I overlooked the second flagellum! I think flagellated amoebozoans (in the Archamoeba clade) mostly have a single cilium, though the type species of Mastigella , M. polymastix , has more. Perhaps a cercozoan amoeboid, then? Cercomonads are biflagellate. But amoeboids are outside my c...
by Bruce Taylor
Tue Jun 27, 2023 12:16 am
Forum: Pictures and Videos
Topic: Stentor amethystinus
Replies: 5
Views: 758

Re: Stentor amethystinus

Yes, they're hard to film! But you did a great job. :)
by Bruce Taylor
Tue Jun 27, 2023 12:11 am
Forum: Pictures and Videos
Topic: SPIROSTOMUM?
Replies: 3
Views: 474

Re: SPIROSTOMUM?

Quite a crowd! :) It's Spirostomum teres.
by Bruce Taylor
Tue Jun 27, 2023 12:02 am
Forum: Identification help
Topic: What a wonder! A new unknown critter!
Replies: 8
Views: 1629

Re: What a wonder! A new unknown critter!

Naegleria is a heterolobosean amoeboid, a group in which pseudopods are formed eruptively (kind of like bubbles erupting from the leading edge of the cell). We don't see that, here: it is moving like an amoebozoan. With those short, digitate pseudopods, I think this is probably a species of Mastiga...
by Bruce Taylor
Tue Jun 06, 2023 1:50 pm
Forum: Pictures and Videos
Topic: The large amoeba Chaos
Replies: 4
Views: 559

Re: The large amoeba Chaos

A real beauty!
by Bruce Taylor
Tue Jun 06, 2023 1:48 pm
Forum: Identification help
Topic: What are these nice freshwater ciliates?
Replies: 2
Views: 1076

Re: What are these nice freshwater ciliates?

The first one appears to be the fragment of a hypotrich (unless you find a whole population of them, in which case we need to look more closely :D). It is moving in a way that looks unnatural, to me, so I think it is a damaged organism and not a recent divider. The second one appears to be a heterot...
by Bruce Taylor
Tue May 30, 2023 2:25 pm
Forum: Identification help
Topic: Litonotus?
Replies: 4
Views: 1251

Re: Litonotus?

Yes, A. procerus ! It resembles Litonotus cygnus , but has multiple contractile vacuoles and a little fan of extrusomes at the tip of the proboscis. The two-part macronucleus is a very common feature in members of the order Pleurostomatida, so it's not too useful as a character of the genus or speci...
by Bruce Taylor
Wed May 24, 2023 3:43 am
Forum: Identification help
Topic: Ciliate or Turbellarian?
Replies: 8
Views: 1592

Re: Ciliate or Turbellarian?

It's oddly shapeless, for a flatworm. I don't know much about them, unfortunately. It crossed my mind that it might be a freshwater acoel, but I really have no idea.