How many offspings can Dermestidae have?

[nomihoudai]

Today I got a visitor of a kind that didn't please me.

In a box of several specimen which contained specimen that spent 1 year on the spreading board in an open room I noticed a dislocked moth head and later found frass under one specimen. Inside the specimen was 1 larvae of a Dermestidae sp. in last instar.

Now my question is not how to prevent for these beetles because there is many topics on insectnet about it, but I wondered how many offsprings can a Dermestidae beetles have ? Do they lay single eggs on single specimen ? Are the larvae territorial? When can you see them from the outside? Is it possible that other specimen are infected too and contain a first instr larvae on the inside where I see no frass?

Are single larvae the exceptions that always happen now and then or is it a first sign of an army of beetles that will attack my drawers?

For my collection, I keep the unmounted specimen in air tight containers. I keep the mounted specimen in wooden drawers after letting them dry for a month on spreading boards. The above specimen were an exception of specimen that I forgot to put off board. I do not have any form of poison in my drawers as I want to resign to chemical poisons in my home as much as possible.

In the past 3 years I only lost 2 specimen to Tineinae sp. larvae and I have some Psocoptera sp. on my spreading boards but I have never withnessed them doing any harm.

Thx for any help

[Deleted]

Claude, I have no idea about the reproduction mechanics of derbastards but one thing I do if a specimen is going to be on the boards for a long time is I put nathalene at the front and rear of the specimen thus ensuring that they stay away until it goes into the drawer which are always well stocked up anyway, I know that you said you dont have any form of poison but this has always worked well for me.

[Adam Cotton]

Reducing the humidity should get rid of the Psocoptera. They will "do harm" over a period of time, especially if they suddenly explode in numbers, when they can strip specimens' wings very fast.

WRT Dermestids, note that the 1st instar larvae can even get inside 'airtight' draws. The adults often lay eggs on the outside of a draw and the larvae crawl in after hatching.

Sorry, I also have no idea how many eggs a female Dermestid can lay, but I'd guess it would be at least a hundred.

Adam.

[nomihoudai]

Ok thanks for your inputs so far. I know I need to change something with my spreading boards. I probably will try to vacuum-clean each time when I finish using them as the Psocoptera feed on the left over scales and they live in the pin holes, so impossible to get them. I have so far never seen one alive in one of my drawers.

For the dermestidae, it would sound logical for me too that a female would lay hundreds of eggs, but this does not match up with my experience so far. I sometimes have them in my appartment in summer too and then I only see the last instar larvae individually siting here and there. I have never found them in large number. The only place where I saw several of them was on "infected" saturniidae in the museum, but then on the other hand I do not know if there was only one larvae at a time feeding one after the other on them or if there actually was a group getting together.

The moth in my drawer must have gotten infected during the time on the spreading board, I tried to google some papers on the topic and saw that the larvae cycle takes some months, so it should have grown prior to getting into the drawer (I put them in there 2 months ago or so).

Maybe some more people can share their experience and clarify if my poison free collection is screwed or if it was just an exception. Nevertheless I put the other butterflies from the drawer now in the freezer at -20°C and will let them stay there until April 2012. There had been some rare butterflies from my home country in there too and I could not let these specimen get harmed in any way.

[wolf]

OVER 9000!!!!

i just had to claude

[lordpandarus]

The Psocopteras are my main enemies. I occasionally get a specimen ruined by them

Freezing doesn't seem to get rid of them

[Adam Cotton]

Oct 31, 2011 14:04:37 GMT -8 lordpandarus said:

The Psocopteras are my main enemies. I occasionally get a specimen ruined by them

Freezing doesn't seem to get rid of them

You should re-freeze your box about 10 days after you remove it from the freezer. Freezing often will kill all the insects, but not their eggs. Since they hatch in 7 days re-freezing after 10 days should solve the problem.

Adam.

[timoinsects]

my method.

1.
dry them in airtight box natually, light bulb heating seems not very good for unmounted/spreading specimen drying. so natually as enough.

determists are unable to access in,even if they are able to. but the camphor cube kills them very effectivlly. as it is airtight.

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[lordpandarus]

Good idea

[timoinsects]

or this way is good also.perhaps better.

transperent plastic air tight bags that put insects in with some camphor.

if want as best as possible,then put thouse bags in a air-tight box, and freeze to kill dermestid.

dermestid were found also outside the insects, when i see some "soil" around a specimen,that means dermestids are happilly having food. then freeze. cold to death.

my favourate specimens were storaged very well,but some not favoured specimens,small part of them suffered from 2 dermestid sp. and included which,one sp. is the worest and often occur.

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[nostrodamus]

""Freezing doesn't seem to get rid of them ""

I found yesteday also some Dermestidae in one box, I'll put today the box in a fridge minus 80°C in the lab where I work.

Can they survive minus 80°C ?? (= minus 115 Fahrenheit), That can't be possible ??

THX

David

[nomihoudai]

They won't, "freezing doesn't work" refers to the temperature range a convenient freezer can operate in ( -20°C at max), every freezing inhibiting substance has it's limit.