Help with killing agent.

[maliciousinchworm]

Hello all,

Used to be Geometridae in the old forum, from now ahead MaliciousInchworm (don't know why I couldn't register with capital letters, I feel it spoiled the nick!)

Some friends of mine are going in collecting trips to the tropics and they will collect some stuff for me. It's supposed that I'll get some moths, and among them probably Geometrinae, that as you know, usually show a striking green color.

I would like to get opinions and tips on which method should they use to kill the specimens. Does Ethyl Acetate make these colors fade? Any better chemical? I would much appreciate any help, and please, don't tell me pinching, this is unpractical when you have 500 moths in your sheet!

Regards,

Alejandro A.

[admin]

I use ethyl acetate for geos, but very carefully, because they are so delicate. My method does not involve pinching. I try to get them off the sheet and into the kill jar without using a net and without touching them with my fingers. Then I only leave them in the kill jar long enough to knock them out, but not kill them. About 30 seconds, depending on the strength of the fumes. Then I immediately remove them from the kill jar with forceps, carefully fold their wings shut with forceps, and carefully insert them into a small glassine envelopes. Always be sure your killing fluid does not touch the moth, you need some kind of a separator in the jar. Plaster of Paris is best. Cotton is not so good because the moth's feet will get caught in the cotton.

I put the envelopes in a cooler. Since the moths are not completely dead they will not dry out on the way home. When I get home I put the envelopes in a Ziploc bag and into the freezer to kill them. Then they are very easy to spread when you are ready. Just thaw them out.

As far as I know ethyl acetate does not harm the colors.

That's my story and I'm sticking to it.

[boghaunter1]

Hi Guys,

From my experience the delicate greens found in the Geo's (& in Luna moths & in the Feralia moths) are probably one of the most unstable colours/pigments. If left in an ethyl acetate killing jar for too long they will turn entirely yellow & get so stiff they are unmountable (ruined). Just my personal experience...anyone else? & Yes... Clark's method of a quick knock down for less than a minute & than freezing works great, although certain specimans, no matter how carefully handled still lose their beautiful fresh colour...turning pale white/yellowish tinge.

John K.

[admin]

Jan 4, 2011 14:37:01 GMT -8 boghaunter1 said:

Hi Guys,

From my experience the delicate greens found in the Geo's (& in Luna moths & in the Feralia moths) are probably one of the most unstable colours/pigments. If left in an ethyl acetate killing jar for too long they will turn entirely yellow & get so stiff they are unmountable (ruined). Just my personal experience...anyone else? & Yes... Clark's method of a quick knock down for less than a minute & than freezing works great, although certain specimans, no matter how carefully handled still lose their beautiful fresh colour...turning pale white/yellowish tinge.

John K.

Timing is everything in this procedure. I don't use much juice in the jar because it does indeed stiffen these small moths. So a very mild dose for geos is essential. I use a very strong dose for muscular moths like Catocala because I need to immobilze them immediately before they damage their wings. But I never use a net for Catocala because invariably their thoraxes get rubbed on the fabric, creating the dreaded shiny spot on top.

I haven't noticed any fading of geos due to the killing agent with my method. But exposing a geo collection to sunlight for long periods of time will fade them fer sure.

Here's an example of a cat with perfect fur on the thorax.

Attachments:

[saturniidave]

I have found that a lot of green moths also lose their colour when relaxed in a moist atmosphere, all of the Emerald moths will turn buff-yellow. it also affects other green moths so beware.
Dave

[timsbugs]

I like Ammonium Carbonate for small moths and you can safely pack it in your luggage.

Tim

[maliciousinchworm]

Thanks all for your help, I find Clark´s method very interesting I may propose this.

saturniidave: yes, I also have this problem, I got some green Geometridae from Uganda and when I relaxed some of them got soaked and lost colour, I don´t really know if that was caused by moisture or grease though, as I have also suffered the later problem, and I guess I can´t use any chemical to make the fat go away. In Europe we don´t have too many green ones, most I got in a night was some Geometra papilionaria and Hemithea aestivaria, but not in numbers, things changes in tropics, as always...

timsbugs: As you are the only one using Ammonium Carbonate here I would like to get some further explanations. Does this product hardens stuff. What about green colors, should I worry? I would also like to know if DNA sampling could be attemped later, as this is one of the cons when using Ethyl Acetate.

Thanks in advance

Regards,

Alejandro A.

[timsbugs]

Alejandro I think if you are worried about DNA, then you need to pinch.
In my experience Ammonium Carbonate has never caused color fade especially with greens, and keeps specimens very pliable more so than ethyl acetate.
In a properly loaded kill jar it takes only seconds to incapacitate a small Geometrinae.
Then I follow Clark instructions.

For my kill jar I use a plastic peanut butter jar with AC in the bottom and half way up I place a perforated piece of foam cut a little larger than the inside diameter of the jar, wrapped in soft tissue paper. This prevents the gas from escaping to quickly when you remove the lid and has a much quicker recovery time. For small moths this works by far the best for me.

Tim

[Chris Grinter]

In my traps I use ethyl acetate, which works just find 99% of the time. Protecting those sensitive greenies are tough, but only a small portion of my green Geo's fade on me (or other green moths for that matter). Usually that happens when relaxing, not after sitting in a trap all night. As long as the specimen is dry, you should be just fine! The one disadvantage of EA is that if you over saturate the killing chamber you get precipitation onto the walls and specimens, causing damage. This happens to me quite a bit when I'm in the field and recharging my jars on the fly - I'll squeeze too much EA into my jar and it gets everything wet (which is why I'm back on cyanide only).

I've tried ammonium carbonate and really disliked it. The killing power is not as good as EA and you then risk having a moth flap around in a jar for longer.

What sort of DNA are you worried about? If it's just COI then you basically shouldn't worry about your killing method, they can get decent sequence data from dried specimens that are 20 years old, let alone something killed last week. If you are doing more sensitive sequencing work then EA should still be fine, it does not do the damage that cyanide can sometimes do. Of course if you're really doing careful sequencing, you should place the specimens directly into 100% EtOH and freeze (freezing is more important than the EtOH).

Chris

[maliciousinchworm]

I was nearly sure that ammonium carbonate, or more exactly, a carbamate based insecticide was what I was needing. In fact I was already searching for any shop selling carbamyl. And now again you make me doubt about his killing effects again, this is going to be a headache...

I was thinking of submitting some legs to the iBOL project after I've ID the specimens, when I remember correctly they extract their sequences from COI, so according to you they shouldn´t have severe problems.

Any of you have ever used pyrethrin based insecticides, they look promising to me. I may try this myself during the collecting season to study its pros and cons. I have been unable to see any references to its use in entomology, but a brief note on canopee foggers used by a museum on a research of Amazone Rainforest insect diversity.

I will keep gathering info.

Regards,

Alejandro A.

[entoman]

My prefered method for any insect is freezing. Of course this would not be very practical for someone without quick easy access to a freezer, and good collecting spots in the tropics are not famous for abundances of these . Hope you get a good catch.

[damesd]

Thanks for starting and/or contributing to this thread. I and my family are doing collecting in the Philippines and have two issues:

1) larger specimens becoming damaged in jars
2) local unavailability of ethyl acetate in quantities less than 1000 liters (LOL).

I have not yet tried Ammonium Carbonate. We have been using ethyl acetone with mediocre results (of course). I have avoided pinching because I don't want to damage the scales on the bodies or undersides. A freezer is not readily available to us most of the time, as we're usually out in the jungles.

I appreciate your insight and advice and any further comments people can give.

[Chris Grinter]

For very large animals you should inject acetate/ethanol/ammonia. Pick up a pack of insulin syringes (easy to get in the USA at least) and you can get pretty good at stabbing a moth once it has settled down on a sheet without touching it. Only a tiny drop of ammonia kills instantly.

[Adam Cotton]

Jan 4, 2011 10:26:21 GMT -8 maliciousinchworm said:

Hello all,

Used to be Geometridae in the old forum, from now ahead MaliciousInchworm (don't know why I couldn't register with capital letters, I feel it spoiled the nick!)

You can change the displayed name by going to Profile and clicking on the "Modify Profile" link, where there is an option to change the name displayed, but you still have to log in using the original version.

Adam.

[damesd]

Feb 18, 2012 23:34:05 GMT -8 Chris Grinter said:

For very large animals you should inject acetate/ethanol/ammonia. Pick up a pack of insulin syringes (easy to get in the USA at least) and you can get pretty good at stabbing a moth once it has settled down on a sheet without touching it. Only a tiny drop of ammonia kills instantly.

Thanks, Chris. I appreciate the help. Any Philippine leps that would interest you if I come across them?