Hyalophora euryalus - hi-all-oh-for-ah yur-ee-ah-lus - the name rolls off my tongue like a little jingle and makes me happy at the thought of this burgundy and gray moth with long white fang-like crescents. My first introduction to this beauty was as a teenager at a summer camp when I found a freshly-emerged male on the screen door of the girls cabin one morning in the Methow Valley of Okanogan County. I was instantly smitten and have long wished to rear this species from egg to adult. I might have done it sooner if I was inclined to stay out at night at the right time of year and set out some black lights, but sleep and daytime butterflies were a stronger pull!
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| Ceanothus silkmoth (Hyalophora euryalus), May 7, from Vancouver, WA |
On May 7, a friend in Vancouver, WA posted a picture of a giant moth outside her garage...not only was I excited to see that it was female, but I noticed what appeared to be two eggs stuck to the siding! A few messages back-and-forth later, my friend had the moth captured in a large container and I could barely concentrate on work the rest of the day before I drove the 45 minutes to her house. Sure enough, there were two eggs still stuck to the siding, so I gathered those too and returned home with my prize. Over the next few nights I gathered a total of 81 eggs before the moth expired.
Ceanothus silk moth adults, like other giant silk moths (Saturniidae), do not eat and only live about a week. You might think of the adults as the equivalent of flowers: visible and pretty and allow plants to reproduce, but don't last very long.
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| Hyalophora euryalus eggs |
I gave half of the eggs to a colleague who studies Saturniids. He advised me to split the brood between Douglas Fir and Pacific Madrone because the larvae will look quite different in the final instar (a hostplant-induced morph). 39 of my 40 eggs hatched a week and a half later. Because the eggs were laid over several nights, the larvae hatched over three or four days; the first ones doubling in size by the time the last ones had finished hatching. This variation in hatch date and growth rates has resulted in larvae of many different sizes even though they are all from the same parent.
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| Eggs starting to hatch! |
Butterfly and moth caterpillars hatch relatively quickly and with little warning (some eggs turn clear but these don't) so I've never had the opportunity to capture the moment when the caterpillar crawls out of the egg...until now! While watching the caterpillars that had already hatched, I noticed an egg moving and a caterpillar head breaking out of the end, so I grabbed my camera and quickly took several photos.
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| Hyalophora euryalus larva hatching |
May 19-22
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| Hyalophora euryalus - newly-hatched 1st instar |
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| Hyalophora euryalus - newly-hatched 1st instar |
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| Hyalophora euryalus - newly-hatched 1st instar |
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| Hyalophora euryalus - newly-hatched 1st instar |
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| Hyalophora euryalus - newly-hatched 1st instar |
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| Hyalophora euryalus - newly-hatched 1st instar (left) next to mid-1st instar (right), only three days apart! |
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| Hyalophora euryalus - late 1st instar larvae |
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| Hyalophora euryalus - late 1st instar larvae |
May 25-29
Great photos! I'm raising some euryalus cats right now too. Fun times.
ReplyDeleteGlad I found your site. Just found one on my door in Chehalis Washington. Had no idea what I was looking at. Also had a giant water beetle visit this spring too. The bugs are super sized .
ReplyDeleteFound one of these beauties a couple of weeks ago…I have never seen anything like this. I was blown away by the size and colour. I am now on the hunt for caterpillars! The bugs are absolutely super-sized this year. I have seen more species of moths this year than ever before. Located in Coldstream BC
ReplyDeleteSaw one today at sycamore state park near Malibu CA
ReplyDeletePlease help, I found one in terrible weather, let it go, and it came back or never left, it was on itS bAck, stuck to wet wood, so it stayed another night, does not eat, but slightly weak but wants to leave, ( I think), it’s cold, for this area this time a year, waiting to let go in a while, hopefully bats won’t be around by then…
ReplyDeleteHi, sorry for the delay but I was having trouble posting comments. These moths do not eat as adults and only live a few days, so it is possible that you found one that was already on its way out. There isn't much you can do to help them out other than to put them in a protected place during the day where they are out of notice of birds and squirrels and can fly away at night.
DeleteWhat do they eat? Got some eggs right now
ReplyDeleteHi, I just found one of these today and brought it home on its host plant. I’ve raised anise swallowtails for years but never this one. It seems to be at the 3rd i star. But it keeps wandering around like it’s looking for something, reaching up. In addition to the plant (I think willow) that I found it on I’ve put manzanita, Douglas fir and birch with it. Any idea why it’s not eating? I’ll take it back if it doesn’t start eating. Any ideas? Thanks!
ReplyDeleteLarvae do not eat for about two days before each molt. Usually they don't move either, but it might be wandering a little because it was disturbed. If it was on willow, it probably won't switch to manzanita or Douglas-fir. If it is a full-grown larva, it may just be looking for a place to start spinning a cocoon. Either way, just give it a couple days to see what it does, and make sure the leaves stay fresh and any open water is completely plugged up so it doesn't drown (like where the stems go into a vase, they'll often crawl down into the water and drown). There's also a possibility it could be parasitized, which may affect its behavior.
DeleteThis may be a silly question but do they produce actual silk?
ReplyDeleteYes, it’s a lower quality than what Bombyx mori produces (what is commercially farmed), but the silk of some Saturniidae species are sometimes used in certain cultures, especially historically.
DeleteFound one of these on the ground while walking my dog. I live by Lake Cle Elum and haven't seen one before. They are so beautiful!
ReplyDeleteI caught a healthy adult in our living room -attracted to the lights - in north Lake Tahoe and placed ot in a clear container with a napkin lining. Over 3 days it laid about 100 eggs in the container then slowly died so I pinned it. The eggs were idle for about a week then hatched over a few days. I currently have about 75 tiny caterpillars that had little movement at first, but once I placed a few gooseberry branches in the container they began to eat and they're currently growing fast, approx 0.125in long. Curious to see them grow and go through the different stages!
ReplyDeleteI just saw on of these beauties in my yard for the first time in my life. We live in northern BC, so I think it must be a rare occurrence to see one all the way up here. It was absolutely stunning.
ReplyDelete