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This can't be good - black lines on Monarch chrysalis

weed30 St. Louis
5 years ago
last modified: 5 years ago

I have three Monarch chrysalises that were brought in as eggs. The eggs were perfectly white, no mottling to indicate a problem. They are about a week old, all green, except the one below, which I have now isolated. It looks like someone took a Sharpie and drew lines on it. The rest of the chrysalis is perfect. What do you think is wrong?



Comments (24)

  • Iris S (SC, Zone 7b)
    5 years ago

    Never seen this before. Was it like this the whole time? It almost looks like the tentacles (what I always thought were antenna, but got corrected here) are stuck on the outside.

  • weed30 St. Louis
    Original Author
    5 years ago
    last modified: 5 years ago

    I just noticed it today - it was facing sideways in my cage and I usually only saw the "profile", so this might have been there the whole time. That is the place on the chrysalis where the antennae develop. (And they are antennae. Tentacles are on the caterpillar - the shorter fake antennae looking things towards the back of the caterpillar are tentacles, which are there to fool predators.)

  • Jay 6a Chicago
    5 years ago
    last modified: 5 years ago

    I read something saying dark markings on Monarch crysalises is a sign of OE infection. The parent of that caterpillar probably picked up the pathogen further south from infected milkweeds that the owner did not disinfect. My heart goes out to you. Set it free, and pray for a miracle. On the other hand, I'm not sure what the experts would say. Is it better to release the butterfly so it can continue to spread the pathogen? I don't believe in killing for any reason. Experts say almost all infected Monarchs die before ever reaching Mexico and Southern California. They say this is a good thing, because this way the wintering populations don't get infected. Anyone growing tropical milkweeds or others that are perrenial in the south needs to hose off their plants or periodically cut them down to prevent spreading this pathogen to any more Monarchs. Maybe the kindest thing to fo would be to keep the adult caged, so that it can't spread the infection. It won't live long after heading further north.

  • weed30 St. Louis
    Original Author
    5 years ago

    I have had chrysalises with OE in the past, and the pattern of dark markings with OE is typically random and diffuse. These are very defined lines, and the rest of the chrysalis is normal, which makes me think it's something else. I've never seen anything like it personally or on the web, and I've been raising Monarchs for 12 years. Perhaps it's something as simple as a genetic anomaly.

    It's really interesting if nothing else, and I'll be curious to see how things progress. I'll add to this post so those interested know what eventually happens.

  • Jay 6a Chicago
    5 years ago
    last modified: 5 years ago

    There is a test to confirm OE infection, by pressing a piece of tape to the adults abdoman, and then looking for the OE spores under high magnification. I hope you are right, and it is only a genetic anomoly. It could just be part of the butterfly, showing through the crysalis early.

  • Iris S (SC, Zone 7b)
    5 years ago

    Please let us know how it goes. I am very interested. Looked at some images online last night, nothing came even close to yours.

  • weed30 St. Louis
    Original Author
    5 years ago
    last modified: 5 years ago

    I definitely will. It looks the same today, except now I can see faint wing lines through the chrysalis, so at least I know it's not a wasp or fly maggots in there.

    I emailed a butterfly expert at UC Davis and he didn't know either. I am worried that the butterfly's antennae or legs, if that's what those black lines are, will be stuck to the chrysalis and it won't be able to eclose properly. If it's the legs, I know they can survive without them*, but if it's the antennae, not sure.

    *I've read many times that butterflies don't have pain receptors like we do, but I just can't fathom actually amputating them.

  • weed30 St. Louis
    Original Author
    5 years ago

    Well that was fast. The chrysalis continued to darken all day, and this morning is completely clear. I put it in a very small "critter cage" and I'm taking it to work with me so I can assist eclosure if needed. I'll report back later!

  • Iris S (SC, Zone 7b)
    5 years ago

    Can’t wait. Hope is has a good outcome.

  • Iris S (SC, Zone 7b)
    5 years ago

    Yay! Congratulations!

    weed30 St. Louis thanked Iris S (SC, Zone 7b)
  • HU-947571875
    3 years ago
    last modified: 3 years ago

    I'm GLAD to see this. I know this is from a couple years ago but I'm seeing the same thing with a chrysalis just now. I'm glad to see there's reason to think it may be alright. Thanks for the photo, too! It's almost exactly what the chrysalis I'm wondering about looks like. Those are raindrops, as well.


  • Mars SC Zone 8b Mars
    3 years ago

    Dead thread!

  • rhizo_1 (North AL) zone 7
    3 years ago

    HU-947.....you are more than welcome to bring up an older thread that you find interesting, especially when you have something useful to add to the conversation. Great image, by the way.

    HU-912.....

  • Mars SC Zone 8b Mars
    3 years ago

    what happen?

  • archietexture
    3 years ago

    A butterfly thread is always looking to eclose info to newbies! Bought three milkweeds to put out for passing monarchs...what I actually bought was a baby nursery. First time...about thirty crysalis percolating in the net cages I bought for other reasons. Just happened to have them in hand! 🦋

  • woodrose
    3 years ago

    There are tons of information in old threads. If you search for something it's going to bring up old threads.

    I don't mind them at all. I've learned a lot from reading old threads.

  • Nat Welch
    2 years ago
    last modified: 2 years ago

    Yesterday a toddler at my sons preschool pulled a monarch caterpillar off a plant which was doing the J thing and it lost its silk attachment. We bpught it home to try to save and last night it dropped it's skin and same time dropped off plant while it was soft and there noticed small amount of green liquid surrounding skin.. I've carefully hung on plant and just noticed these black lines - it's also far smaller than the other crysalis... does it have a chance??


  • Mason
    2 years ago

    I know this is an old thread. But, I wanted to comment that this exact thing just happened to me. Probably a week and a half after forming, a chrysalis randomly developed this large black dot that looked like it was drawn on with sharpie. Today, the butterfly emerged perfectly healthy, with the black dot still attached to the chrysalis.

  • Pam Henry
    2 years ago


    Sorry for the grainy photo, changed 4 days ago. Does it look healthy as far as you can tell?

  • archietexture
    2 years ago

    I also had a cat that began to form it’s chrysalis on a leaf, then fell a short distance and “bled” a bit of its green fluid. I rehung it after it appeared that the chrysalis was sealing back as it hardened. It survived and successfully became a butterfly I released.

    I also had two other harder falls during the 2021 season that did not survive so I quickly euthanized them.

    I think the first post asking about the diagonal lines differs from the damaged chrysalis pictures. I had one do that and it’s the butterfly’s antenna forming. The chrysalis is clear. You can begin to see the parts of the little beasties as it gets closer to the time they are to eclose.

    Start your milkweed seeds SOON, place seeds in the north on soil once cold is there for good (cold, not freeze). Step on them gently to make contact with soil. Nature will cold stratify for you and milkweed will emerge in its season!

    Throw some in woodlands or ditches near you!

  • archietexture
    2 years ago

    OE infection leaves blotchy, uneven marks about the body of the chrysalis. Chalcid wasp infection turns the chrysalis a sickly shade of green to start as it continues to turn a kind of brownish green as the cat dies. Then the little horrors emerge (thankfully coralled by the mesh tent! Only had one but that was plenty. Dozens and dozens of tiny wasps!)

    Normal coloring as the cat changes is symmetrical. The two sides will be mirror images.

    OE and parasites cause asymmetrical discoloration.

    My first year, over 250 successful Monarch butterflies released! Two black deaths, 3 wasp infestations, 3 fall deaths, a shed load of thrills, squee!!!, sharing and enjoyment!

  • archietexture
    2 years ago

    Note to anyone getting those mesh cages to raise indoors: you’ll want to have them near a window, but not getting cooked in direct sun. Keep cages facing same direction North, South, E or W that you had it facing when they J. Part of their migration mystery is their ability to tell direction, which some studies I read was influenced by the chrysalis phase. (ALL my cats J’d in exactly same direction.)

    Indoors it’s helpful to gently mist plants and keep moist air during chrysalis phase as well. My A/C had a tendency to dry them out and so I tried to watch when they eclosed in case they needed a midwife ;). Leave them alone generally, but occasionally I needed to gently assist several to get out of the chrysalis, if they weren’t out in a minute of eclosing. The abdomen begins pumping right away and if the wings aren’t free to expand they’ll deform and it won’t be able to fly.

  • Maureen Vialard
    last year


    I also have one with markings, anyone have a guess?

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