First attempts at 10X, Nikon CFI60 on Canon tele

[papilio]

It's pretty nice having images like these filling the sensor now instead of being just low-res detail crops.

100% pixel views available as the flickr Original size.



Dicranocephalus wallichi bourgoini, scarab




Acroncinus longimanus, Harlequin longhorn beetle
Tarsal claw



Antenna joint



What are these setae doing beneath the exoskeleton?








3.5X, MP-E macro


Apologies for the filthy subject matter here, very old specimens.

[rjlittlefield]

This beetle must have been ready to molt, most of these setae are beneath the exoskeleton.

Fascinating observation!

That conclusion would be appropriate for a spider, but not for a beetle. Beetles don't molt after they emerge from the pupa.

I have no idea what's really going on, though. Exactly what body part is this? Does it look to you like this might be a bit of pupal skin that the adult was not able to shed?

--Rik

[papilio]

This beetle must have been ready to molt, most of these setae are beneath the exoskeleton.

Fascinating observation!

That conclusion would be appropriate for a spider, but not for a beetle. Beetles don't molt after they emerge from the pupa.
--Rik

I didn't think so either Rik!

But just to be sure I too quickly googled the matter and it said yes at each place I checked, so I thought I must be wrong though I'd never seen such a thing. Seeing those hairs really did have me convinced that I'd been mistaken all these years.

I have no idea what's really going on, though. Exactly what body part is this? Does it look to you like this might be a bit of pupal skin that the adult was not able to shed?

I think not, this is a joint on the antenna, folded around the body during pupation. Very strange. (Sorry to have posted too hastily to have noted the ID of the image.)

Somebody here must know what we're seeing there, obviously beetles were not my area of interest, more strictly Lepidoptera ... spiders are a very recent excursion.

[Bathcat]

Beetles do not molt, as Rik said, but I have found that there can be considerable amounts of grease suspended on the surface of the exoskeleton of my pinned specimens. As the "surface" in those pics seems to have no microsculpture, I'm thinking it might be regular body fat that has leached out and settled on the surface of the specimen.

To clean them up, improve the color, and free identifying setae on mine, I put the pinned specimens on a small piece of balsa wood and then suspend that upside down in small metal cans originally intended for car polish or paint, about 2/3rds full of acetone or ethyl acetate. Give it about three days in there (I set mine on the porch as both of these chemicals are health hazards), and change out the solvent as it turns brownish (sometimes this takes several rounds of different specimens). Acetone is easily found at most car parts stores, along with those clean metal cans. Avoid using plastic containers, especially with ethyl acetate, as it will dissolve them, give you at best a distinctly plasticky new coating to your pinned insects, and at worst a potential firebomb.

edit: to clarify, beetles do not molt in the adult stage of life, as a spider, bug, cockroach, or other arthropod with incomplete metamorphosis would. If something on the net is saying beetles molt, I assume that's in reference to the self extrusion they perform to escape their pupal cases.

[papilio]

Thanks Bathcat! I find that quite remarkable about the appearance being caused by grease leaching out, it certainly would account for the lacquer-like appearance. I've just never seen my insects this close before! The complete lack of microsculpture pretty much clinches it. Interesting look though, quite pretty I thought.

I appreciate especially the cleaning instructions! I've used acetone quite a bit in other work, fascinating that it would clean my specimens up ... something which I've been meaning to inquire about on the forum, so thank you.

I collected insects up through high school, that was my primary passion at the time so I certainly should have known better ... rather than taking the word of Wikianswers which stated simply "Do beetles molt? Yes they do." Good grief, rather embarassing ... I just figured that was another one of those facts about which I'd been wrong all my life. lol


[Edit] Bathcat, do you mean that the specimens should be suspended in the space above the surface of the acetone or submersed? Thanks!

[Bathcat]

Stick the bugs on the underside of the balsa wood, so they're submerged below the surface of the acetone. I put headless insect pins in the top of the balsa float to easily pull it back out.

And no problem! If I can help a few people with my narrow experience, it's a small trade off for the plethora of questions I've asked and will continue to ask about optics in general

[papilio]

Great, thanks again Bathcat!

[rjlittlefield]

rather than taking the word of Wikianswers which stated simply "Do beetles molt? Yes they do."

Thank you for clarifying where the mis-information came from. I did a Google search on wikianswers do beetles molt and was immediately directed to http://wiki.answers.com/Q/Do_beetles_moult?#slide=1, "Do beetles moult?". Continuing to the next slide, I saw the simple answer "yes it does".

Well, context is everything, so I thought I would see where this was going. Perhaps, I hoped, they were going to tell me about larvae.

But instead I was aghast to find this sequence:

Q: Do beetles moult?
A: yes it does
Q: How many times does a beetle moult?
A: A lot of times on average, depending on the type of beetle
Q: Does mealworm beetle moults and eats a lot at its larval stage?
A: Yes, it eats a lot at the larval stage
Q: What are beetles?
A: Beetles are bugs which have 6 legs, 2 body segments and a wing case if you see a bug which has all of these it means that you have found yourselves a rolypoly which are beetles.

I know this is just one sequence of questions and answers, but even so I feel quite safe in concluding that wiki.answers.com is not a reliable source of information.

Ironically, but not inappropriately, some sort of information block next to all these "answers" said this:

Supervisors
Stupid little genius
Trust: 2979
Beetles Supervisor

I will resist further comment, though the effort is painful.

--Rik

[papilio]

Haha! Thanks Rik.

That'll teach me to take the word of a Stupid little genius.

[Bathcat]

Reminds me of certain places I've worked. If they'll just answer with confidence, well, they must be the expert

[NikonUser]

There are at least 2 questions here. The answer depends on which is asked. If I was asked "Do beetles moult" I would answer, "Yes, all insects moult".
If the question was "Do adult beetles, the imagines, moult" the answer would be "No".
Worth remembering that an immature beetle, ie., egg, larva, pupa, is still a beetle; and so to be clear one would have to specify which stage of the insect is being considered.

[papilio]

You're correct of course NU.

And I'd like to believe that Mr. little genius on Wikianswers just failed to make that distinction ... but I wouldn't push it.

[rjlittlefield]

I was actually OK with the part about beetles molting, especially if it had been clarified that only the immatures molt.

Where I lost patience with wiki.answers was at "Beetles are bugs which have 6 legs, 2 body segments and a wing case if you see a bug which has all of these it means that you have found yourselves a rolypoly which are beetles."

The odd thing is that these "supervisors" actually seem to have real identities. If you go to the wiki.answers page and click the link for "Google profile", you'll be taken to a page that provides a lot more information.

--Rik

[papilio]

I quite agree, Rik -- I had only assumed that I must somehow have been reading out of context, but that statement is beyond absurd! lol

So she appears to be quite young, not sure whether that should be an excuse ...