silver-spotted tiger moth ~ 07/24/11 ~ at home

female silver-spotted tiger moth 
Lophocampa argentata

posted 08/11/11 - The verdict is in. I heard back from Paul Opler and Jerry Powell, authors of Moths of Western North America, and Chris Grinter of The Skeptical Moth, the CalAcademy entomologist who first suggested the caterpillars I found and raised were L. sobrina. They all agree this moth that pupated 05/01/11 and emerged 07/23/11 looks like L. argentata.

Here's what Chris had to say about it, "I had assumed it was sobrina based on location - Monterrey [sic] peninsula is the type locality of sobrina and where all of our specimens of are from. I have to dig into our rare book room with a librarian to find the original description, but I doubt it will help differentiate the two species being that it's form [sic] the late 19th century. But, if sobrina/argentata are separate then they are nearly identical moths and it might be the case that they can not be differentiated from external morphology alone (genitalia required). I am skeptical that both argentata and sobrina could both be in the same habitat on the same trees at the same time of year - just seems more likely that sobrina is not a true species! (or alternatively, argentata does NOT occur in coastal CA and all of the moths and caterpillars you have seen are sobrina)."

I believe he's going to dissect specimens from CalAcademy to clarify whether there are indeed two distinct species. Here's where collecting does have its uses. However, I released this female moth the day after these pictures were taken. I should have saved her for Chris to compare for his dissections. Sigh, I already felt badly for not releasing her the previous day when she emerged, because she beat herself up trying to escape overnight and there were scales everywhere. The curl at the end of her wings was from her resting at the bottom of the container when she hardened. All in all, she wouldn't have made the best specimen, although I don't know how intact pinned insects are after removing the genitalia.

Oh! The cocoon seen in the first picture is from another moth that began pupation 06/25/11. It still has not emerged. I'll have to go back and correct my caterpillar IDs. I'm adding a new label specifically for this moth; to see my rearing exploits, check out lophocampa.

silver-spotted tiger moth ~ 05/28/11 ~ at home

silver-spotted tiger moth caterpillar (or nameless arctiid moth) feeding on coast Douglas-fir
Lophocampa argentata (or L. sobrina) feeding on Pseudotsuga menziesii var. menziesii
Pinaceae

posted 06/18/11 - I mainly want to show the color variation of these caterpillars that I'm attempting to raise - from bright white to tan side hairs. These three were munching away at young shoots of Douglas-fir. I collected a third caterpillar from the Highlands the day I took this picture on 05/28/11. Add in the two I found around home, I've had 5 total. They seem to prefer hanging out together; in fact, they'll follow each other along a plate's edge like a caterpillar conga line whenever I switch out food. Except for the Highlands Easter caterpillar, I don't know which individuals came from where.

One successfully pupated and has been tucked in its cocoon since 05/01/11, one died 05/21/11 from what appeared to be parasites, and another one died 06/10/11 from what looked to me like typical Btk poisoning - the body was deflated and limp, like a plant that hasn't been watered, with only the middle sets of prolegs keeping the body attached to the nylon top.

I moved the two remaining caterpillars to a clean container. They now occasionally feed on Monterey pine (Pinus radiata) even though I'm still providing a mix of clippings. They rest most of the time upside down from a new nylon top. Their poop has gotten inexplicably smaller. I'm starting to get concerned because they don't seem to be progressing in their development. I suspect they may need a snack of another plant in order to successfully pupate - this is totally wild speculation after reading about Queen butterflies needing to snack on non-host plants in order for their adult pheromones to be chemically complete. I'm starting to remember all too clearly why I once gave up rearing caterpillars. Click to read a past post about how and why I'm raising these caterpillars.

ps 06/25/11 - As I was changing out the tree clippings, one of the caterpillars had started making a cocoon with hairs from its body and silk. I hope I didn't disturb it too much.

silver-spotted tiger moth ~ 05/02/11 ~ at home

silver-spotted tiger moth caterpillar (or nameless arctiid moth) feeding on Monterey pine
Lophocampa argentata (or L. sobrina) feeding on Pinus radiata
Pinaceae

I laughed at how this caterpillar chomps the pine needle like it's eating a giant, long green bean. To see how beautiful this caterpillar is see my 03/15/11 post. As a recap, the pictures of the silver-spotted tiger moth caterpillars (Lophocampa argentata) on BugGuide were browner than what I found in the Carmel Highlands. Hmm? I consulted Chris Grinter of The Skeptical Moth who suggested, based on my location, this caterpillar is L. sobrina; he has since made a comment on BugGuide. Unfortunately, I have not found any other L. sobrina caterpillar images correctly identified on the internet to compare with mine. Actually, there is some question among the experts whether L. sobrina (sorry, there's no common name) is indeed a distinct species from the silver-spotted tiger moth. I also queried Jerry Powell and Paul Opler, co-authors of Moths of Western North America, a hefty book which was released last year. All three moth experts had differing opinions, but Paul had the best advice: raise the caterpillar to an adult to obtain a positive ID. Adult Lepidoptera are better documented and easier to identify. So, that's what I'm doing.

I collected my first caterpillar in the Carmel Highlands on 03/31/11. I found a second caterpillar on 04/20/11 at home and within feet of our local subspecies of the Douglas-fir, L. argentata's favored food. Then on Easter 04/24/11 in the Highlands, I gathered a much larger caterpillar on top of California hedge nettle (Stachys bullata). Finally, I found a fourth caterpillar climbing up the wall nearest the coast Douglas-fir at home. I'm guessing I collected it 04/30/11 while sitting outside to get fresh air, because I returned home from the hospital the previous night. As soon as I found it, I asked Andy to go cut more caterpillar food for me. Gotta love the man! After days of sitting by my hospital bed watching the Food Network (we don't get it at home) in between doctors and nurses visits, while tubes and wires connected to fancy machines beeped and hummed, he then obliged me by tromping through the park to get clippings from various trees. Well, you can guess where my priorities are... must feed my caterpillars first!

silver-spotted tiger moth caterpillar (or nameless arctiid moth) on coast Douglas-fir
Lophocampa argentata (or L. sobrina) on Pseudotsuga menziesii var. menziesii
Pinaceae

I want to show off the cute lemon yellow prolegs of this caterpillar. I have to say, that while these caterpillars did eat some coast live oak (Quercus agrifolia var. agrifolia), they seem to prefer the Monterey pine and coast Douglas-fir. I even tried to feed them various other plants, but they were totally not interested. They also like to feed during the day and get very still at night. Do caterpillars sleep like us humans?

Lophocampa argentata (or L. sobrina) cocoon

This was the largest caterpillar collected from the Highlands on Easter and it started making a cocoon the day before this picture on 05/01/11. Notice the loose hairs mixed in with its silk to make the cocoon? Unfortunately, I disturbed it to move the remaining caterpillars into their roomier home with fresher food.

Lophocampa argentata (or L. sobrina) cocoon lit from behind

I had to see how far along this caterpillar was to pupating, so I held the cocoon up to the light. It wasn't very far along. I've since looked at it again against the light and it looks like it's shed its larval exoskeleton and has the distinctive pupal shape that looks like a turd. I'll try to get a picture of that later.

Lophocampa argentata (or L. sobrina) cast exoskeleton

This may look like a dead caterpillar, but it's not. This is what is left behind when a caterpillar molts in order to grow into a larger caterpillar. I try not to repeat better information that can be found on the web, so if you really want to know, go look it up yourself.

Apologies for this atypically lengthy Nature ID entry. All these pictures were taken on the same day as this post's date of 05/02/11. I've missed doing my blog while I've been sick. I'm now 13 days behind with my posts and I want to catch up. Watch out for multiple posts in any given day...

ps 05/27/11 - Another caterpillar molted this morning and it's very white compared to my other remaining caterpillar of this sp. I was nervous, because it didn't move much for a couple days - I had one die last weekend. I took a close look at the dead one and it looks like some parasite had attacked it. There were numerous tiny cream-colored spots on the underside of its body. I never did get around to pulling out my dissecting scope to take a magnified look.

pss 10/16/11 - Greg Monson, Founder and Head of Production at Lost Nomad Media, requested permission to use the first photo above. With his permission, here's what he said, "I found your post on caterpillars while I surfing the internet. I'm currently editing a research documentary for a professor at the University of Arizona, and your first picture of the caterpillar eating the needle is perfect for a segment in the film where I mention how pine needles are a form of sustenance for insects." He goes on to say, "I'm wondering if I could have your permission to use the photo in my video. The film is a 12-minute short documentary on a research experiment being conducted in Colorado, where they are looking into the role that terpene molecules from pine forests play in generating clouds. It will be published on youtube, and the University of Arizona website, and I will be happy to give you credit for your photo. This is the first of a series of videos my company is producing to promote outreach from the scientific community to the public." I'll add a link to the video when it becomes available.

pss 01/11/12 - Here's the link to the video: http://cals.arizona.edu/research/monson/terpenes.

caterpillars & pupae ~ 03/31/11 ~ at home

moth caterpillars and pupae in containers

Here's my assortment of jars for raising caterpillars and letting pupae rest. No, I don't keep them on the banister all the time. It's often too windy and my friendly scrub-jay is too curious for her own good to keep them here all the time. I just placed some of the containers up there, because I thought it'd make a better photo with the Monterey Bay in the background.

I'm keeping them outside so that they develop naturally. My plan is to record when they pupate, how long it takes to emergence, ID the adults, and eventually release them so they can find mates. I'm generally not a collector anymore, except for photographs. It's been at least 5 years since I've raised anything, but my curiosity about what a couple caterpillars are got the better of me.

Since I've made a policy on Nature ID to post CA nature photos to the date of the actual photos, you'll have to wait for future posts for the close-up shots. I've already posted a close-up of what I hope is a painted tiger moth.

silver-spotted tiger moth ~ 03/15/11 ~ Carmel Highlands

silver-spotted tiger moth (or nameless arctiid moth) feeding on California lilac
Lophocampa argentata (or Lophocampa sobrina) feeding on Ceanothus sp.
Rhamnaceae

It's always a thrill for me when I find a striking caterpillar or two. I'd even say these are pretty. These pictures were taken in a friend's expansive yard just south of Point Lobos, so I can't be sure if the Ceanothus is native or a garden variety. The visual addition of periwinkle and pride of Madeira made for an awesome sight of intense purples and greens. It's too bad I didn't get a step-back habitat photo.

As for the ID of the moth, I am sure it's a Lophocampa sp., but I'm not absolutely positive it's a silver-spotted tiger moth. Based on their size, I suspect these have another instar or two before they're ready to pupate into adult moths. Almost a year ago, bb of biobabbler, Chris Grinter of The Skeptical Moth, and I had a discussion of L. argentata on her blog post of a mystery caterpillar. Most of the L. argentata caterpillar pictures found online are tannish-orange in overall color. In my defense, there are whiter versions like mine (and, no, it's not due to a flash) that have been found at Point Lobos: BugGuide and CalPhotos. Additionally, the literature states the silver-spotted tiger moth feeds on conifers, particularly Douglas-firs. As shown above, they're definitely feeding on Ceanothus blooms. I wonder if location or food preference has anything to do with the color variation of the caterpillars... or if these locals are possibly a different species.

ps 03/23/11 - I originally posted this as silver-spotted tiger moth (Lophocampa argentata). Thanks to Chris Grinter of The Skeptical Moth, I queried Jerry Powell, professor at UC Berkeley and co-author of Moths of Western North America. The three of us had a brief e-mail exchange. Jerry seems to be unsure whether L. argentata and L. sobrina are indeed distinct species, contrary to what his co-author Paul Opler thought. The photo they used in their book of L. sobrina was feeding on blackberry and alder. With Chris's permission to quote him on my blog, here's what he e-mailed, "Yea I think there are deeper problems than just the identification. Only L. sobrina is known from the Monterey area - and identifications of L. argentata from that are are incorrect IF sobrina is a true species. Putting them side by side I do see differences, but they are incredibly superficially similar. I haven't taken a close enough look at the morphology or DNA to actually make a real call. This is a project for another day - but caterpillars of Lophocampa from that area would also be sobrina. The problem with caterpillars is that they are even more variable than adults..." Chris goes on, "I'd say sobrina is the name applied to that population right now. Who knows how long that will stick around for though, there are a few other Arctiinae species in coastal california that share this same problem." Thank you, Chris and Jerry! Who knows, I may have the very first pictures of L. sobrina correctly identified on the internet. Maybe Chris will get BugGuide and Calphotos to correct their pictures?

pss 03/27/11 - I've also contacted Paul Opler who advised me to try to rear these so that I can know for sure which species it is. Hmph! I think I'll do that.

pss 04/20/11 - I realized I haven't posted an update with pictures of this caterpillar. I ended up collecting one on 03/31/11 along with another all black caterpillar from the Highlands. As it so happens, today I spotted something fuzzy on the balcony and thought the one I had collected had somehow escaped. Nope. Now I have two of these caterpillars that seem to like feeding on fresh oak leaves.

spotted tussock moth ~ 06/09/10 ~ Mt. Madonna

spotted tussock moth
Lophocampa maculata

This caterpillar somehow landed on my arm while hiking. It was only about 1/2 inch long and, boy, did it have a lot of personality. I'm guessing it recently hatched and was still in the first or second instar.

ps 06/18/12 - I forgot to include this in my blog carnivals list exactly 2 years ago. I'm happy to report this blog post has been included in The Moth and Me #12 blog carnival, hosted at The Skeptical Moth new site.