Zooplankton and Protist Videos

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Tonight I got some pretty neat clips of a couple specific zooplankton I'm hoping to make positive identifications on, soon.

Species #1

Species #1

Species #1

Species #1
This creature shares similarities with other ciliate.

Example here. Ciliates include parmecium and are protozoa.

Vorticella, another ciliate, from darwin.baruch.cuny.edu
And from Phylum Cilophora, which provides a breakdown of genus and species.

From Kariorelictida: Loxodes, Photography of Ciliates
3/15/07 -- Zooplankton video on youtube.com, video one
The first in the above video, I'd already seen and photographed on several occasions. The second individual which appears, (Zooplankton Video #2) is a new one however. The algae sample I recently took from BCC has set near my bathroom window for a few days, to let the phytoplankton feast on the warm sunshine. I left it there for the past few days and didn't refrigerate. I noticed tonight's slide was full of zooplankton activity -- far more than usual, far more than phytoplankton, including some individuals I haven't seen before in rather large numbers.

Species #2
Species #2
Species #2
Species #2
Some of the strange loops and curves this little creature takes during its swim.


There was a third species
Third Video, Zooplankton and Fourth Video, Zooplankton much smaller than the previous two, which I was fortunate to keep up with briefly, with the camera. These creatures move fast, and sometimes make difficult subjects to photograph or film. Here's that cute little bug again in Video #5 zooplankton, and as its going around in circles another even smaller zooplankton swims by, but is streamlined and shares more similarity with fish.

Species #3
Here's the first species, in video one I wish to identify, caught in Zooplankton video #6.
The second species, caught in zooplankton video #7.

Video #8 Zooplankton shows one of the small zooplankton species swimming beneath what appears very likely to be a deceased ostracod of sorts (favors a small clam), you can still make out the hairs on its shell. Very brief but clear species #2, Zooplankton video #9. Species one is also captured on Zooplankton video #10.

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Stages of Fish Larvae Development

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I've purchased a copy of Zooplankton of the Atlantic and Gulf Coasts (A Guide to Their Identification and Ecology) by William S. Johnson and Dennis M. Allen.

While skimming this book I found many useful and informative sections on groups of zooplankton, including fish. Below is an example of the descriptive illustrations found in this book.

Understanding fish larvae is important in Aquaculture, including knowing the proper timing for changing between food sources, as in transferring fish from hatchery to growout ponds. An example can be found in the sidebar, with a list of catfish life stages.


Typical fish egg




Illustrations from Pg. 270, Zooplankton of the Atlantic and Gulf Coasts
Anatomy of larval fishes, based on naked goby Gobiosoma bosc. Middle illustration shows an early feeding stage that has yet to develop fin rays. The last in the series is a juvenile, which is generally defined as a young individual that is fundamentally the same as the adult in morphology.

Excerpts from Zooplankton of the Atlantic and Gulf Coasts, pg. 269-271
"A few species attach sticky eggs to objects at the bottom, but most are simply released into the water column; some are bouyant and some sink to the bottom (demersal eggs). Fish eggs are usually spherical, from 0.5 to 2 mm. The transparency of most of most fish eggs distinguishes them from the typically opaque eggs of invertebrates. Recently spawned eggs have oil droplets or "yolk" that support early development. Development of an embryo is usually rapid, and often within hours of spawning, the outline of the young larva is easily seen within the egg. At hatching, the now-free larva still has a yolk-sac attached to support early development.
The change from the larval planktonic phase to the juvenile and adult lifestyle often involves "remodeling" of the basic larval body plan, resulting in major changes both in morphology and in functional capabilities. The newly hatched yolk sac larvae grow and develop using nutrients provided in the yolk. As the larvae grow, they add musculature, fin rays, and sensory capabilities. Newly hatched larvae are feeble swimmers, but swimming capablities improve rapidly as larvae grow. Some larvae show schooling behavior at a relatively early age. As swimming speed and endurance increase, some larvae show distinctive patterns of vertical migration that may be associated with predator avoidance, feeding migrations, or selective tidal transport. Early larvae are usually transparent with pigmentation increasing during growth.
When the yolk sac is resorbed, the larvae enter the critical "first feeding" stage where they must find and capture prey in the plankton or perish. First foods are quite small; rotifers, ciliates, and copepod nautilii. Vision develops early, and most larval fishes are visual feeders. Prey are perceived at close range, usually within one fish body length... Prey detection and selection seem to be based on prey size more than on any other factor, but motion and color may come into play. Feeding stops in complete darkness but may continue in moonlight. It is interesting that larvae can see in and feed using ultraviolet light, a capability lost in many adults."

Zooplankton of the Atlantic and Gulf Coasts (A Guide to Their Identification and Ecology) by William S. Johnson and Dennis M. Allen is available at amazon.com

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Proper Algae Plankton Identification

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Here's one example of the problems with identifying algae species, and I haven't really even began documenting what I'm seeing under the microscope.

To give an idea of scale, it's a grain of sand... and beside it sets the organism in question.

Three of them.

Going by the "Aids to the Recognition of Fresh-Water Algae, Invertebrates and Fishes," a brief 24 page paper which my instructor photocopied for me to use... the closest, is Merismopedia. But, that may be wrong. This species could also be, "Crucigenia rectangularis," both look practically the same.

Here's merismopedia.

Needless to say there may be others that look similar or near identical.

I've surfed the web, and really ran into some problems with species identification -- for that matter, proper classification into genus.

This was written by a biology instructor, in regard to the trouble I've had identifying species writes:

The proper way [to collect plankton] is to use properly calibrated and sized plankton filters.

I recognize the eagerness which you show in searching out and trying to identify the enormous range of things you can find. It is what is found in the best students; those truly interested in learning as opposed to those who simply want to get through the required laboratory exercises and go home. Unfortunately, there are not simple answers to questions, even "simple" questions like "what is this". Especially not when the sample comes from teaching aquaria that may be filled with all sorts of exotic things. You are faced with more than the "common pond life" that the simple-minded keys I referred you to are intended to help with.

You are also learning the fact about photographs -- some of yours are unusually good but they simply do not convey the detail of information that a trained eye can see, especially as the trained brain integrates the information from different views and images from different angles. That is why making drawings is so important. In a good drawing, you illustrate those features that are really important, showing them clearly. Of course the Haeckel episode reminds us that drawings are different from real life, but photographs are also different from real life. Making truly detailed and useful photomicrographs is a talent that requires special training and long practice, not to mention rather better microscopes than what you are using. In other words, there really isn't enough detail in the pictures you display to see exactly what many of the things may be. Your commentator on the artscape salt-water-microbes web site identifies things as well as can be expected.

I hate to have to tell you this, but you will have to accept that some things will not be identifiable. That will come with long experience studying with experts. The fact that one of your instructors/mentors, Terri, apparently can't identify it all should be a clue. That is why doing science is a constant learning experience. It really does take years of guided training to do some things and, even then, you still keep learning as long as you live.

So welcome to the world of real science! You are off to an excellent start. You have a long way to go but the entire trip is a fantastic adventure!
- R. Norman

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Centropyxis

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According to Aids to the Recognition of Fresh-Water Algae, Invertebrates and Fishes this creature has the most visible similarities in common with Centropyxis.

Google images produced a variety of similar creatures, so I'll take the chance this creature may be classed among Centropyxis.

Enlarge image to full resolution
Magnified at 100x
Additional photographs of Centropyxis

I don't know, I don't think it's /Centropyxis/. Just doesn't look like it to me. Spines are in different places. Just my 2 cents.

terri
www.ncseagrant.org

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Cypridopsis

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... my site is the official place for errors, blunders and bad identification -- where the information is compiled until it's gotten right.

Here's another that hasn't had any feedback. I photographed two of these.
cypridopsis.html

At least we know the little sketch form the Aids to Recognition is correct. That's one positive. *smile*
-Sharon

I do believe that is an ostracod! Nice find.
terri
www.ncseagrant.org

Cypridopsis


According to table with crustaceans: cladocerons, copepods and ostracods, from Aids to the recognition of Fresh-water Algae, Invertebrates and Fishes

Collection of my Cypridopsis Photos
Cypridopsis Images, Page One
Cypridopsis Images, Page Two
Cypridopsis Images, Page Three
Cypridopsis Images, includes video clips, Page Four


Enlarge Image

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Alonella - Zooplankton

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The Genus Alonella is a group of very small waterfleas. Fine features of the carapace and postabdomen are used to distinguish among species - necessitating use of a high-powered light microscope at a minimum.
Source: Genus Alonella

Large image, 1298 x 1289 pixels, 295 k

I am not certain yet which species this waterflea would be classified among, but I'm positive it's Zooplankton and fairly certain it falls within the genus Alonella.
This photo was created by fine-focusing at two separate depths and merging the photos. Nice seeing its wee little legs (antennae?) in detail.

More Photos and Video of Alonella

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