Funnel extraction

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TonyT
Posts: 88
Joined: Fri Sep 11, 2020 8:30 pm
Location: New Brunswick, CANADA

Funnel extraction

#1 Post by TonyT » Sat Oct 09, 2021 1:23 pm

Christian Autotte showed a simple Berlese Funnel in Micscape Magazine:
http://www.microscopy-uk.org.uk/mag/art ... erleze.pdf
This was based on my more "professional" model.
Such a funnel is incredibly efficaceous for extracting organisms from ground litter. In early October, 2021, I collected about 4 L of litter beneath some shrubs. This small sample produced hundreds of invertebrates including ants, beetles, nematodes, spiders, mites etc. and at least 100 Springtails (Collembola).
I use a vial of methanol to collect the organisms. Individual organisms can be selected using forceps or a pipette.
I "sucked up" 3 Springtails, placed in a small tube (in methanol), added a small amount of Safranin-O . After 2 hours I replaced the stain with clean methanol, moved the springtails to a slide and added a drop of Euparal.
This is a very simple and effective method for collecting, preserving (staining if needed) and mounting small invertebrates.
Attachments
6x21 springtail slide.jpg
6x21 springtail slide.jpg (20.17 KiB) Viewed 334 times
6x21 springtail.jpg
6x21 springtail.jpg (70.04 KiB) Viewed 334 times
New Brunswick
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MicroBob
Posts: 2939
Joined: Sun Dec 25, 2016 9:11 am
Location: Northern Germany

Re: Funnel extraction

#2 Post by MicroBob » Sat Oct 09, 2021 4:19 pm

Hi Tony,
that is a very interesting method you show here, it sounds fairly simple to do. Since I'm always looking for short ways to make interesting preparations I have three questions:

- Why methanol, could it be replaced with Ethanol?
- How long does a slide like this hold up? Do you have longtime experience?
- Is there deformation of the springtail as the Euparal solvent evaporates?

Bob

Ethan1989
Posts: 10
Joined: Fri Sep 03, 2021 6:59 pm

Re: Funnel extraction

#3 Post by Ethan1989 » Sat Oct 09, 2021 7:49 pm

Very brilliant method you had showed and simple too. I think this method is short too but you have not mention that how much time required to change the methanol?

TonyT
Posts: 88
Joined: Fri Sep 11, 2020 8:30 pm
Location: New Brunswick, CANADA

Re: Funnel extraction

#4 Post by TonyT » Sat Oct 09, 2021 8:03 pm

Bob,
I like to use absolute alcohol. I can't obtain ethyl; I can get 99% Isopropyl from the drug store (chemists), but quite expensive.
100% methanol is available from a hardware store for a much lower price.

The beauty of using Euparal is that one can mount directly from absolute alcohol. I have read that a Euparal slide is good for 50 years.

A Canada Balsam slide is good for 150 years. Could be used as a mountant but it will tolerate only very small amounts of absolute alcohol. To use
CB one would have to add one further step, such as xylene or another clearing agent. Euparal is the simplest.

Deformation: Springtails mounted earlier today, so far no deformation. Will take another look in a few days.

I took a look at the Springtail mounted in CB in November 2020 (specimen in my Micscape Magazine article). Perfect!
So perhaps it is worth going the extra step and mounting specimens in CB.

Ethan:
I use about 50 mL methanol in the vial (90 mL urine sample vial); after 24 hours I remove the vial, put on its screw cap, and either look at the contents or store it for later inspection.
Replace the 1st vial with another, 24 hrs later replace #2 with #3. If specimens are still 'coming out' of the sample I extract for a further 24 hrs.
To look at the sample I pour the contents into a large weighing dish, select any I want for processing and return everything else to the vial
New Brunswick
Canada

MicroBob
Posts: 2939
Joined: Sun Dec 25, 2016 9:11 am
Location: Northern Germany

Re: Funnel extraction

#5 Post by MicroBob » Sun Oct 10, 2021 6:21 pm

Hi Tony,
it is interesting how different situations are in different coutries: I can get Ethanol with some additions for acceptable money, and most of the additions can be destilled away. 99,9% Isopropanol is even cheaper. Methanol has become difficult to obtain, I don't know why.

Bob

TonyT
Posts: 88
Joined: Fri Sep 11, 2020 8:30 pm
Location: New Brunswick, CANADA

Re: Funnel extraction

#6 Post by TonyT » Fri Oct 15, 2021 7:44 pm

It has been about a week since I made the Springtail slide, looked at it today - absolutely no shrinkage.
I made a similar mount for this ant from the same funnel extraction (100% methanol, direct mount into Euparal).
This is a 'hard-bodied ant', not surprising that there is no shrinkage:
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ponera 6x21.jpg
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TonyT
Posts: 88
Joined: Fri Sep 11, 2020 8:30 pm
Location: New Brunswick, CANADA

Re: Funnel extraction

#7 Post by TonyT » Wed Oct 20, 2021 8:48 pm

Quite a bit of discussion on a mite from a funnel extraction
viewtopic.php?f=6&t=13967
New Brunswick
Canada

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