MicrobeHunter.com Microscopy Forum

Sorry, I didn't realize they were quite so little. In that case besides Achnanthes , the little diatoms Cocconeis are domed one one side and flat on the other, which has a subtle raphe and striae. They can colonize surfaces very densely, but normally have C-shaped chloroplasts and I haven't heard of...

Some diatoms do stick to plants, but these don't look any to me. They are apparently flattened but with no plain girdles or raphes, and I would expect such an intact group to have many with full chloroplasts, instead of each having at most one irregular brown clump. More important, they are also pac...

This is a neat video of feeding. Here the target is a bacterial mat, where everything is stuck together for protection, and that's why the rotifer has to graze at the edges instead of its current sweeping things in from farther away. Then at times you can see the mastax or pharyngeal jaws grinding a...

Like others have said, this is what cladocerans look like when they are not viewed from the side. You can still see the branched second antennae and the bivalved carapace. This is actually a ventral view, with the detail showing the gap between the valve margins. But even though it's not the usual p...

The general shape may be similar, but these are not euglenoids. Trachelomonas and most other green kinds have only one flagellum long enough to extend out from the cell, which tends to undergo a looping motion. A few like Eutreptia have a second but are more spindle-shaped and less rigid. They also ...

Kind thanks, everyone. :) 75RR, I did allude to my page and it's linked from my profile and vimeo, but I much appreciate the explicit endorsement! jwsmith, how much this is protective is I think an interesting question. The earthworks might be an artifact of being on a slide, and the ciliates didn't...

I'll second that these seem like dinoflagellates, particularly if they were flattened. Those have two flagella from the middle, but the anterior one is tied around the girdle so not very apparent. Most are brownish, yellow, or green. This would probably not be Peridinium , which are armoured so more...

Hello all. I haven't had much to post here; I have my own page for photos, have been idle for videos, and both are rather less spectacular than what you find here anyway. But I thought some might enjoy a repost of a video from the old forum, since there is now much more to say about it. I had origin...

This is not truly a shrimp, which for instance have stalked eyes, but is from another line of crustaceans called amphipods. I think the spines on the abdomen and lack of any apparent branch on the antennae mark it out as a Hyalella , at least among North American genera; I don't really know if other...

Bonjour seb, very lovely. If you don't mind a correction, this is not a Cymbella but instead looks like an Amphora . Both have crescent-shaped valves, but in Cymbella each has a central raphe I am sure your photo would show. In Amphora the valves are more tilted, so that cells often rest like this, ...

Many heliozoans are that small, but this should be Pandorina, a type of colonial green flagellate. You can see the cells packed together and a few of the flagella that were close to the focal plane. They can be reasonably fast but do sometimes end up sort of turning in place.

Are "water mites" related to "sea-lice"? Not too closely. They're both part of the arthropods, a giant phylum of animals like insects, crustaceans, millipedes, spiders, and so on, which share segmented bodies with jointed legs. But within that group they are as far apart as possible. Sea-lice are c...

Interesting find. There are some sessile protozoans that reproduce with little buds, but amoebae and most others split more evenly in two. This is it expelling undigested material, it looks like the case from a diatom it had eaten.

The last image shows a mite, which have a pair of palps at the front but no antennae. It looks like a larva, having 6 legs instead of the adult 8. The surrounding algae are some Oscillatoria -type cyanobacteria and little golden diatoms. These are all types that can't really be identified further wi...

Have a provisional ID, subject to confirmation as usual: Vaucheria sp. It is not a Vaucheria , which do not have cross walls dividing them into separate cells. Most filaments like this are difficult to tell apart, but your first photo captures something very distinctive to go on: a series of rings ...

What you would excise there would be the same insects that are on earth today... Any other mysterious shapes or dark spots contained there will be nothing more than a smidgen of ancient plant material or just plain DIRT... That seems a pessimistic take. It's true enough if you consider one fly or b...

Hi Luke, very nice set. I think you're probably right in all your identifications. For Carchesium I thought it might be useful to note that you don't have to guess if the contractions are separate, as some books make it sound, but can look at the contractile filaments in the stalks. In types like Zo...

This motion applies to bacterial flagella. However the flagella you find in flagellate protozoans and other eukaryotes are very different; they sometimes do move by whipping back and forth, or make coordinated strokes like in Chlamydomonas , undergo complex looping like in Euglena , glide along the ...

This is definitely an oxytrichid but they are unfortunately hard to tell apart, even with a video as nice as this. You can see the three longer caudal cirri but they are not really distinguishing for Stylonychia . My understanding is that in combination with the front end widened to one side, only s...

Also in the last photo is the shrimp dead. It showed no movement at all. It's an interesting question. It's plain there is nothing alive there - no eye, no gut, no sign of organs - but I think it might not be dead so much as departed . Ostracods are really a separate lineage from the larger crustac...

Like 75RR said the last image is a statoblast, which are resting stages of bryozoa, and I think such oval ones are characteristic of plumatellids. I expect the other images are then new bryozoan "polyps" or zooids, or maybe ones that broke off a colony, of the same type; different types are largely ...

This is a good video of an interesting sample, but if you will allow a correction, it doesn't actually show a Lacrymaria . Those have a very flexible and extensible neck with a distinct "head" at the end, which I am sure your video would show, and I don't think the tail point is ever quite so long. ...

Well, I don't think I count as an expert, but I will vouch for it being a diatom. lukem321 points to the colour, and that's actually a very good place to start for identifying algae since it relates to different types of photosynthetic pigments, which tend to be conserved within groups. Yellow-brown...

I will second Monostyla , now usually treated as part of Lecane , but the other is not a Euchlanis . You can tell by how the foot is inserted; in those it tends to be broader and comes out a gap between dorsal and ventral plates, which sort of shows as a curved line around the back. Here instead the...

This doesn't have as heavy a lorica as the ones I am used to, but the foot and in particular the spines at its base should mark it as a Trichotria , and some of the pictures you can find online look very similar. Euchlanis are built differently, with a shorter foot inserted in a gap between larger d...

The larger ciliate swimming around at the beginning is a chlamydodontid; Chilodonella and Trithigmostoma are the ones mentioned most often, but there are several different kinds with minor differences in cilia. In general though most are flattened and oval with the front margin skewed toward the rig...

Hi Jim, This is a neat find! It is not a Paramecium , which have a prominent oral groove, as well as some other features you might expect to see here like a contractile vacuole in each half. Here there is one terminal vacuole and you can make out a mouth with pharyngeal rods at the front, typical of...

Like others said, this is definitely a Euglena . Not only is there the eyespot characteristic for euglenids in general, but there is the stretching and compressing you mention. That's a type of motion called metaboly, caused by sliding of the distinctive protein strips euglenids have; in contrast gr...

gekko is right, it's definitely not a nematode. I've never seen any so broad or without an apparent digestive tract, and being contractile confirms it; they would only have the muscles to bend side to side, which is how they move around since they lack cilia. A flatworm makes more sense. The famous ...

For identifying unknowns like this it's often helpful to know where they were found. There are some plants with trichomes that look very similar, for instance shown here or here, if some might reasonably be in your sample.