See No Weevil…Well, Just One

A big nose never spoiled a handsome face.

~French proverb

I set out the moth light the other night and had a few species come in, but had many non-moth visitors – katydids, a praying mantis, lots of caddisflies, and one very interesting little guy, a weevil.

weevil at moth light

Weevil on sheet at moth light (click photos to enlarge)

Weevils are the largest family of beetles with over 3000 species in North America. They are distinguished by often having a distinctive snout (rostrum) with chewing mouth parts at the end, and antennae part way down its length. They are plant feeders of one sort and many are considered agricultural pests, but, they sure are interesting and crazy-looking creatures. The Kaufman Field Guide to Insects of North America states that hardly any plant is not affected by at least one species of Curculionidae.

weevil close up

Close-up view of that amazing rostrum

My visitor the other night looks like one of the acorn weevils, Curculio sp. They are tan to brown with a long rostrum and spurs on the femurs of their legs. Weevil antennae are elbowed and can fit into a special groove in the snout.

weevil on rail 1

Acorn weevil

I am guessing this may be a female since they tend to have longer snouts, at least as long as their body. So, she has probably been using the mandibles at the tip of that “nose” to chew holes in some of the many acorns out back. She then turns around and lays an egg into that hole. Her baby will feed on the meat of the nut and then chew its way out and pupate in the soil once the acorn falls. I reported on the fascinating grubs of acorn weevils in an earlier post. No matter your opinion on the dietary costs of weevils, you gotta admit, they are one odd-looking, and some may even say, cute, critters.

 

 

Snippets

Life moves pretty fast.If you don’t stop and look around once in a while, you could miss it.

~John Hughes

Indeed, life has been moving too fast of late, with so many things happening at work and in our personal lives. Luckily, I work in a magical place, and it doesn’t take much time to find something of interest – a short walk across the garden for a meeting, a trip out to my car, or just doing some of the outdoor chores that need doing, there is so much to see, if you just pay attention. It also helps when my co-workers and volunteers find something and drop me a note or give me a call. That was what brought many of these snippets to my attention this past week. Here are some of the highlights from the week of what you can encounter in a native plant haven like the North Carolina Botanical Garden.

Monarch butterfly at NCBG

Monarch butterfly stretching her wings after emerging from the chrysalis (click photos to enlarge)

monarch chrysalis with tachind fly pupa

Some monarchs are not so lucky. This one was brought to me by a wonderful volunteer. She was hoping to release an adult butterfly, but a tachinid fly larvae emerged instead. Its pupa is the brown case beneath the damaged monarch chrysalis.

caterpillar with parasitoid eggs on dorsal surface

Tachinid flies are common parasitoids of many butterflies and moths. But I had never found a caterpillar with the white eggs of one of these flies on it until I stumbled across this one this week.

green lynx pider under hooded pitcher plant

This female Green Lynx Spider laid her egg sac in the protected cover of a Hooded Pitcher Plant.

green lgynx spider and young

Another Green Lynx female sits next to her recently hatched spiderlings atop a Cardinal Flower seed stalk.

green lynx spiderlings up close

These Green Lynx Spider babies have molted once and will soon disperse away from their protective mother.

Cope's gray treefrog juvenile

After our wet summer, the Garden is now alive with many tiny Cope’s Gray Treefrogs.

black swallowtail prepupa

A co-worker alerted me to this Black Swallowtail pre-pupa one afternoon this week. Knowing it would shed one more time and reveal the chrysalis in the next 24-hours, I brought it to our volunteer training  the next morning.

black swallowtail just after chrysalis formed

I carried the pre-pupa along on a training session and, right on schedule, the last molt occurred and everyone was able to witness the amazing transformation to the chrysalis.

A Week of Moments

The butterfly counts not months, but moments, and has time enough.

~Rabindranath Tagore

Monarch hanging on chrysalis

Monarch butterfly shortly after emergence from its chrysalis (click photos to enlarge)

Last week was a busy one (actually, aren’t they all) at work with getting everything back out after the hurricane and preparing for and delivering several programs. And yet, it was still a week full of natural history highlights, brief moments when the beauty and mystery that surrounds us reveals itself and I take a moment to pause and wonder. Here are a few of those moments…

_

One of the horticulture staff spotted this female marbled salamander (females have gray markings, males have white  ones) among the soil around some plants in the Display Gardens. She will be laying eggs soon in a wetland depression and will guard them until rains fill the pool.

Hearts-a-bustin seed pod at NCBG

Seed pods of Hearts-a-bustin, Euonymus americanus, one of my favorite native shrubs of autumn.

Purple-crested slug after molt

A purple-crested slug moth caterpillar (Adoneta spinuloides) that has recently molted.

I did a lunchbox talk at the Garden last week on one of my favorite topics, caterpillars. So, in spite of the postponement of the museum’s BugFest event due to the hurricane, Melissa and I were still able to go out one evening and collect a few for my talk (sounds like the prefect date night, doesn’t it).

Caterpillar with wasp coccons

This larva has fallen victim to a wasp parasitoid. The white silky blob beneath the caterpillar are the wasp cocoons. One study estimated that 10 to 25% of all last instar caterpillars are parasitized by wasp or fly parasitoids.

Turbulent phosphila larvae

The day after my caterpillar program we discovered this group of turbulent phosphila moth larvae feeding on their host plant, greenbrier. It can be hard to tell which end is which on this gregarious feeder.

Plume moth

Certainly one of the stranger-looking groups of moths, the plume moths, resemble tiny gliders.

Mantis with bee

The week ended rather poorly for this male carpenter bee that was prey for this Chinese mantis.

Goldenrod and wasp

Fall is just around the corner when the goldenrods (Solidgo sp.) are in bloom.

 

Be sure to take the time to find some moments in your week ahead.

 

Florence Cats

If you spend your whole life waiting for the storm, you’ll never enjoy the sunshine.

~Morris West

Florence has already had a huge impact on things here in the Piedmont, far away from her predicted point of landfall. While this is minor compared to what people in the more direct path of the storm will have to deal with over the next several days, many schedules in this area have been rearranged and many things canceled or postponed with the storm’s approach. One such cancellation was one of my favorite events of the year, BugFest, at the NC Museum of Natural Sciences. As predictions of the stormy weather grew, it seemed less likely we would need to scour the fields and forests for caterpillars for our annual show of the diversity and beauty of the larvae of butterflies and moths of our region.

But some things are hard to give up. What does a caterpillar-lover do when all the preparations have been made for any wind and water headed our way? Why, you stroll through the yard looking for caterpillars, of course. So, below are a few species discovered this afternoon (and a couple from earlier in the week) while we wait for any impacts from Hurricane Florence.

Monarch larva, last instar

Monarch caterpillar (click photos to enlarge)

Black swalowtail larvae on rue

Two instars of Black Swallowtail larvae – notice how different this species looks in different stages. The larger instar is often mistaken for a monarch due to similar colors and patterns, but note the yellow dots inside the black stripes and the lack of black tentacles on either end compared to a monarch.

Florida fernth larva mo

Florida Fern Moth larva on, what else, a fern

White furcula side view

We love finding “Furkys”. Here is a White Furcula caterpillar on wild cherry

White furcula ventral view

White Furcula, ventral view

Double-lined prominent larva dorsal view

Double-lined Prominent on elm

_-2

A mystery Geometrid moth larva on spicebush…anyone know this one?

Fall webworm

The most common caterpillar in the yard right now, the Fall Webworm, found now on almost any plant

White flannel moth dorsal view

A treat to find a White Flannel Moth larva on redbud, as it has been a few years since I have seen one of these odd beauties..

White flannel moth side view

This clownish looking caterpillar is one of the so-called “stinging caterpillars”, with tufts of urticating spines that can cause a bee-sting-like pain should you touch it.

And a couple from earlier this week at work…

Datana sp. getting ready to molt

Datana sp. larvae just prior to a synchronous molt

Drab prominent larva

A Drab Prominent caterpillar looking anything but…

Stay safe if you are in the path of the storm, but remember to take a moment to enjoy the beauty and wonder that surrounds you.

 

 

Hot Holiday

It’s summer and time for wandering…

~Kellie Elmore

After I retired (you remember back when I was retired) I loved the fact that I could go to some of my favorite places on a week day when fewer people would be out and about in the wild places I love. I certainly didn’t want to go on a holiday weekend when even more people created crowded campgrounds and busy highways en route to my favorite destinations. Well, that was then and this is now, so off we went last weekend on a camping excursion. It was prompted, in part, by a visit from Melissa’s cousin, Kevin, from New York. He had not traveled much in these parts so she had given him tips on where to camp and hike in the mountains on the first part of his visit and now we were going to share a couple of our favorite things with him down east – paddling in a swamp and looking for bears.

The first day we drove to Pettigrew State Park where we had reserved a site, set up camp, and then headed to the nearby boat launch on the Scuppernong River just outside Creswell. We had debated whether to try the entire 12 miles to Columbia (something we both have always wanted to do) but we decided to go ahead, despite the threat of thunderstorms.

IMG_5917

Upper reaches of the Scuppernong River (click photos to enlarge)

We put in about 1:30 p.m. and headed toward Columbia (we shuttled one car down there at the take out point). Melissa and I have paddled portions of this river several times and have seen a bear each time, so we had high hopes. No sightings this trip, but we think we heard a couple splashing through the swamp as we paddled. We also saw many pileated woodpeckers, wood ducks, a barred owl, a bald eagle, and had a constant escort of dragonflies.

Paddling the Scuppernong

Paddling the tranquil Scuppernong. We saw lots of pileated woodpeckers and heard a couple of bears splashing in the swamp.

Scuppernong lower reaches

We were alone along the entire 12 miles of river until we got to Columbia

Scuppernong near Columbia at sunset

A tranquil ending to a beautiful day on the river

We managed to dodge the thunderstorms and ended the day with a slick-as-glass water surface at sunset.  After a delicious dinner in Columbia we headed back to camp where another storm stopped just short of the campground. The next morning we headed over to the Pungo Unit hoping to show Kevin a few bears and other critters in our favorite area of the state.

Young Eastern box turtle in road

Our first wildlife of the day – a young Eastern box turtle

We started kind of slow but did see 5 bears by mid-day. My favorite was one sacked out in a tree right next to the road.

Young black bear in tree

Melissa spotted this sleepy bear lounging head down in a tree right next to the road

Young black bear chillin' in tree alongside road

This is one sleepy bear

We took a break from Pungo and drove over to Mattamuskeet National Wildlife Refuge. After observing some waders (including a nice little blue heron and a tri-colored heron), a tour of the visitor center, and a short hike along one of the boardwalks, we headed back to Pungo. Kevin was driving to Richmond that evening so we wanted to try to find as many bears as possible and maybe have a few opportunities for photos before he headed out. Pungo did not disappoint…

Black bear and cub

Momma bear and cub on “Bear Road”

We saw a couple more as we drove the refuge roads and then decided to head to one of my favorite places, “Bear Road”. It wasn’t long before we saw the first of 14 bears! The sow above had two cubs of the year hanging out with her (only one is visible in the pic above), and we saw several other individuals and another sow with cubs. But one bear provided the highlight of the day…

Black bear walking toward us

This young bear was hurrying toward dinner in the cornfield near where we sat

Black bear realizing something is not right

The moment when you realize – wait, what are those things?

A young, beautiful bear (probably a 2 or 3-year old) came out of the woods and headed down the road towards its evening meal of corn. We were sitting in the road near the corn field and the bear strolled along until, suddenly, it realized something was amiss. It did what we all have probably done at one time or another…trying to decide which course of action is the best…go back, continue on to where I was headed, but what about…then a hesitation, a look back and forth, and finally, what the heck, I’m going. So, the bear scurried into the canal and over into the corn and disappeared.

Black bear trying to decide what to do

Do I stay or do I go?

Black bear indecision

But the corn is just over there…

We ended the day with 25 bears, including a few with cubs of the year (always fun to observe), a couple of bears standing up to check their surroundings, and a bear in a tree. It turns out, if you pick your destination carefully, you can still go somewhere even on a holiday, and not experience the hassle of crowds (unless you count the bears). A great outing on a hot holiday weekend. Can’t wait for our next visit.

Mothing, Part 2

Look closely. The beautiful may be small.

~Immanuel Kant

The last post had some recognizable moths, some big ones, some brightly colored ones. But countless moths are frustratingly small (when you are trying to identify them), and many are, at least at first glance, LBT’s (little brown things). But the magic of a macro lens is that it brings out their beauty once you enlarge them on your screen, making it somewhat easier to flip through the pages of a field guide until you find one that is similar. Yet they are all beautiful in their own way and worthy of our attention and appreciation. Once again, if I have made an ID error, I welcome comments and corrections.

Here are some of the littler ones that came to the moth light. I love the variation in shape, colors, and patterns of these tiny night-time visitors.

Orange-tufted Oneidannn

Orange-tufted Oneida, Oneida lunulalis (click photos to enlarge)

Black-marked inga

Black-marked Inga, Inga sparsiciliella

Redbud leaffolder, Fascista cercerisella

Redbud leaffolder, Fascista cercerisella (the diminutive black and white larvae fold the leaves of redbud)

_-2

Olive Arta, Arta olivalis (this little moth seems to be standing at attention)

Suzuki's Promalactis Moth, Promalactis suzukiella

Suzuki’s Promalactis Moth, Promalactis suzukiella (this tiny moth was not in my Peterson Field Guide to Moths of the SE U.S.; introduced from East Asia)

Bent-line carpet, Costaconvexa centrostrigaria

Bent-line Carpet, Costaconvexa centrostrigaria

Bent-line Gray, Iridopsis larvaria

Bent-line Gray, Iridopsis larvaria

Common angle

Common Angle, Macaria aemulataria (the description says this moth has dark markings on its forewings that resemble paw prints)

Brown panopoda

Brown Panopoda, Panopoda carneicosta

Curved-tooth geometer moth, Eutrapela clemataria

Curved-tooth Geometer Moth, Eutrapela clemataria

Dead wood borer moth

Dead-wood Borer Moth, Scolecocampa liburna (larvae bore into dead logs/stumps of hardwoods)

Deep yellow Euchlaena

Deep Yellow Euchlaena, Euchlaena amoenaria

Faint-spotted Palthis, Palthis asopialis

Faint-spotted Palthis, Palthis asopialis

Drexel's or Major Datana?

Major Datana, Datana major (this group is difficult for me to separate, so this may be one of the other Datana species – they all look very pettable)

Oblique-banded Leafroller, male  - Choristoneura rosaceana

Oblique-banded Leafroller, Choristoneura rosaceana (this one looks like a stocky person wearing a cape)

Garden Tortrix Moth, Clepsis peritana

Garden Tortrix Moth, Clepsis peritana (another “caped” moth)

_

Planthopper, Flataloides scabrosus (this one fooled me, I thought it was related to the two moths above, but a closer look showed it did not have moth antennae and is instead a very weird planthopper – thanks to Steve Hall for the ID)

Changenable Grass Veneer?nn

Changeable Grass-Veneer, Fissicrambus mutabilis (one of the group that always rests head down)

_-4

Beautiful Wood Nymph, Eudryas grata (Adults perch with their fuzzy forelegs splayed outward)

Beautiful wood-nymph

Beautiful Wood Nymph, Eudryas grata (A truly beautiful and unusual moth – when disturbed they drop to the ground as if dead)

Mothing, Part 1

…to understand something of the wonders of a world which becomes the more wonderful the more we know of it.

~W.J. Holland, in The Moth Book, 1903

_-3

A sample of moths (and some other wee beast) attracted to my black light (click photos to enlarge)

I set out my moth light for two nights a little over a week ago to see what species might drop by here at the house. Melissa and I gave a moth program at work the week before that and, though we didn’t get a tremendous number of moths that night (in part, due to the early hours for families), it did reignite my moth fever. One night I put the sheet on the clothesline out the basement door. The second night I strung it up on the back deck outside the living room. Both nights I turned outside lights on in addition to having a black light set up next to a cotton sheet. I checked the lights from sunset until about 12:30 p.m. both nights. Things started slow and peaked between 11 p.m. and midnight.

The thing I find so fascinating about moths is their diversity and beauty when you actually take the time to look at them. Many are, at first glance, just brown nondescript bugs, seemingly impossible to tell apart. But a closer look, and their colors and patterns are incredible. I do find them very challenging to identify, but there are a host of online resources that can really help. Among my favorites are: Moths of North Carolina, Bug Guide, Butterflies and Moths of North America, and the North American Moth Photographers Group.

But the real game-changer for me was the publication last spring of the Peterson Field Guide to Moths of the Southeastern North America. I had purchased their guide to moths of the northeast when it came out a couple of years ago and it had been helpful, but, obviously, not comprehensive for our region. But my copy of the new guide is already showing signs of wear as I have flipped through its pages countless times searching for a species new to me at the lights at home or at work. The challenge in moth identification is looking for key characteristics. A look at the online resources for any one species reveals the amazing variation between individuals of some species. And, of course, the printed field guide has space for only the most common variety (generally only one picture is chosen to represent an entire species’ variability). So, having said that, I have done my best (along with Melissa’s help) to identify these to species, but there is a chance some may be misidentified. If anyone catches a mistake, please share in the comments section.

Below are some of the larger moths (those approximately an inch or more in length) that came to the lights. More of the smaller ones will be shared in my next post.

How many of these have you seen?

Banded or sycamore tussock moth

I love the pattern and colors of this moth. It is either a Banded Tussock or a Sycamore Tussock Moth (Halysidota tesselaris/harrisii). They are apparently very difficult to tell apart, and both caterpillar species are common here.

rosy maple moth

One of the more common species at the sheet was the beautiful Rosy Maple Moth, Dryocampa rubicunda.

Luna moth

Always happy to see a Luna Moth, Actias luna.

Angle-winged emerald, Chloropteryx tepperaria

There are other green guys out there – like this Angle-winged Emerald, Chloropteryx tepperaria.

Red-spotted emerald

Red-spotted Emerald, Nemoria saturiba.

Drab prominent?

Drab Prominent, Misogada unicolor.

Mottled prominent, Macrurocampa marthesia

Something appears to be wrong with the wings of this Mottled Prominent, Macrurocampa marthesia.

White-blotched heterocampa

White-blotched Heterocampa, Heterocampa umbrata.

Oval-based prominent

Love the shoulder pattern on this Oval-based Prominent, Peridea basitriens.

The Laugher, Charadra deridens

Moth common names are fascinating, like this one – The Laugher, Charadra deridens.

The Hebrew

The Hebrew, Polygrammate hebraeicum, so-named because the black markings somewhat resemble Hebrew script.

False Underwing - Allotria elonympha?

False Underwing, Allotria elonympha.

Stripes

These caterpillars come in brilliant green, pink and yellow, banded, and striped forms that often look nothing at all like each other.

~MOSI Outside blog post

If you are not a fan of bugs, then you may want to take a break from this blog for a bit because it is what is happening right now (oh, there may be something on bears or birds soon, but bugs rule this time of year). Yesterday at work I got an email and a voice mail from two staff about some cool caterpillars in our lower nursery. Comments ranged from do you know this guy, some sort of sphinx? to as big as a hot dog. Of course, I had to go see.

Banded sphinx larva reddish-green form

Banded sphinx moth (Eumorpha fasciatus) caterpillar (click photos to enlarge)

When I arrived, several staff were working in the nursery and pointed out the “hot dog” larva (it was about the size of my index finger). I recognized it as a banded sphinx. It was the characteristic shape of a sphinx moth larva, but lacked the true rear “horn” of most other hornworms. And the diagonal stripes are oriented in a different direction than those of most other sphinx species larvae (these slope from the abdomen upwards towards the head, whereas those in most species, like tobacco hornworms, go from the abdomen upwards toward the rear). But it soon became apparent that this beauty comes in many stripes…

Banded sphinx larva red form

A nearby banded sphinx with a different dress code

We found several more caterpillars, many with a more reddish color scheme.

Banded sphinx larva green form

And who is this guy?

Then, as I was walking out, I spotted another sphinx on the same host plant (Ludwigia sp.) but with a totally different pattern. I assumed it was a different species, but when I checked my field guide, I discovered that banded sphinx larvae come in two forms – a heavily striped one and a green one.

A close-up comparison of the three major color morphs of this species we found yesterday is shown above. Amazing variety for one species! And they are beautiful from every angle.

Banded sphinx larva reddish-green form dorsal view

Looking good from above…

Banded sphinx larva reddish-green form ventral view

…and below

Banded sphinx larva reddish-green form ventral view close up

You gotta love those “socks”

If you think these caterpillars are amazing, here is a look at the adult banded sphinx moth…

Banded sphinx moth

Adult banded sphinx moth

This moth was sitting at the front door of the Allen Education Center one morning earlier this summer. I took it out of harm’s way and snapped a couple of photos before releasing it. Perhaps some of those amazing caterpillars are descendants of this individual. Discovering several of these stunning caterpillars is one reason I find it so interesting working at the NC Botanical Garden. The diversity of native plant species makes for an incredible richness of fauna as well. Every day, a new discovery!

Caterpillar Clusters

Groups tend to be more extreme than individuals.

~Daniel Kahneman

In spite of the heat and humidity (or maybe because of it), this is one of my favorite times of year – caterpillar time. The period between mid-August and mid-September tends to be the best time to find the greatest variety of interesting caterpillars in this part of the world. Most species are nearing the end of their larval life and are getting larger, the amazing parasitoids and predators are reaching a peak, and many of the caterpillars are getting ready to pupate, which usually means they will be on the go looking for a suitable spot making them more likely to be encountered out in the open.

_

Caterpillars clustered on an oak leaf (click photos to enlarge)

This past week I had a few nice encounters with a bizarre behavior – caterpillar aggregations (or clusters). The first was a group of Datana sp. (they can be tough to tell apart) larvae clustered on the back of an oak leaf in front of one of our buildings at work. Garden staff had alerted me to them so I walked over and grabbed a couple of quick pics in between what has been constant rain these past two weeks.

_-2

Aggregation of walnut caterpillars on tree trunk

The next day, I checked on the oak leaf, and the cluster was still there, huddled together. I wasn’t sure whether it was the weather, or perhaps an impending molt, causing this behavior. When I got back to my office, another coworker texted me a photo of what looked like a blob of caterpillars on a tree trunk next to her car. This one was a bit more dramatic (as she said, it looked like a squirrel had been squashed on the side of the tree). This group looked like walnut caterpillars, Datana integerrima. They are hairier than the other species from earlier in the day, and this species feeds only on trees in the Juglandaceae family (black walnut, hickories, pecans, and butternut).

_-3

The pile of larvae was huge and several caterpillars thick

This species is known to form large aggregations, often 2 or 3 caterpillars deep, on tree trunks (this larval pile was about 12 inches long and wrapped about 5 inches around the hickory trunk). It turns out this is a phenomenon called synchronous molting, and is fairly common in several species of Datana larvae. I looked online for information on how they manage to coordinate the timing of their molt, but was unable to find a definitive answer. I assume they are able to communicate with pheromones which may impact hormone levels that trigger the molt.

_-4

A close-up view of the hairy mass

This process may take a couple of days before they finally shed and head back up into the tree to continue feeding. But why do these caterpillars cluster? Looking through several resources it seems there are a few theories: thermoregulation (clustering together increases body temperatures of the individuals); feeding advantages (feeding together in groups may help overwhelm plant defenses); and the most likely, anti-predator/parasitoid defense. Datana larvae typically display a defensive U-shape, raising the tip of the abdomen and arching the head and thorax back. They exude what is presumably distasteful liquid if the threat continues. They also exhibit synchronized head-flicking in response to an approaching flying predator or parasitoid. The time just before and after a molt is a very vulnerable one for caterpillars, so it makes some sense to aggregate and combine defenses, although it may also make them more vulnerable to being discovered by certain caterpillar-seekers like hungry birds or curious humans.

Walnut caterpillar sheds

Shed skins of walnut caterpillar cluster (compare to second photo above)

After work that day, I decided to go back out to the walnut caterpillar cluster for a few more photos. As I approached, I could see something was different. The cluster was not as noticeable as I approached their tree. They had all shed! The cluster now looked like a week-old squirrel carcass stuck to the tree, and almost all of the caterpillars were gone, presumably up in the canopy feeding. What a difference a few hours made. As I looked at the pile of shed skins, a slight movement caught my eye a few inches away from the heap of husks…a line of small caterpillars clinging to a green briar (Smilax sp.) vine,

Turbulent Phosphila early instars

Early instar turbulent phosphilas on Smilax sp.

These little guys are turbulent phosphilas, a favorite of mine, both for their odd name and their strange color patterns. I am more familiar with their latter instar where they are adorned in bold black and white stripes and more prominent fake eye spots that make it hard to discern which end is which. Learn more about them in an earlier blog post. I am glad to find these small larvae. Maybe a few will make it until BugFest (coming up September 15!).

I walked over to the other caterpillar cluster on the oak. They had also molted after at least two days of hanging out on that one leaf.

Datana on oak just after shedding wide view

Newly molted Datana sp. larvae on oak leaf (compare to first photo above)

I am still not quite sure which species of Datana these are…most likely either Contracted Datanas, D. contracta, or Yellow-necked caterpillars, D. ministra.

Datana on oak just after shedding side view

Arched defensive posture of Datana larvae

As I maneuvered the branch for a better photo, the cluster began to twitch and assumed the defensive U-posture common to this genus. Teamwork against a perceived threat.

Datana on oak just after shedding

Cozy caterpillars

Though they looked content all gathered together, I assume they eventually dispersed back up into the leafy regions of the tree. I am thankful to work in a place with such biodiversity and that these larval congregations were all in places so accessible that they allowed me to share a few moments of wonder with them.

Harvey

The larva of the Royal Walnut Moth is a striking object. With its curved horns and numerous spines it presents to the uninitiated a truly repellent aspect.

~W.J. Holland, in The Moth Book, 1968

Hickory Horned Devil

Hickory horned devil caterpillar (click photo to enlarge)

I must agree with Mr. Holland in that I have seen many “uninitiated” people react with horror on their first sighting of a hickory horned devil. But I, and many of my caterpillar-loving friends, think this gargantuan larva is one of the sweetest finds you can make on any summer walk in the woods. And that is exactly how I reacted a few weeks ago as we hiked out to Morgan Creek with our 16 summer campers for some creek dipping. As we neared the creek bottom, I spied some frass (caterpillar poop) in the trail. Anytime I find a cluster of frass on the ground (especially large ones like this), I look up in anticipation. After some searching, I found it, and was thrilled to see it was a hickory horned devil. It was feeding on sourwood, a host species I have never found one on before. I left it until we had finished with the creek sampling and then collected it on the way back to the classroom.

The kids were amazed at its size and further astonished that it still had some growing to do before it was done as a caterpillar. We named it Harvey (why not?) and they excitedly checked on it every day. On Friday, Harvey stopped feeding and hung under a branch, motionless. I decided to take it home for the weekend to watch it and provide fresh food, but the larva did not move until Sunday morning when I looked in and saw this…

hickory horned devil after shedding its skin

Hickory horned devil after shedding its skin

Harvey sat motionless for two entire days prior to this molt. He remained in that position much of that morning and then finally turned around and began to eat his shed skin, something I have seen these larvae do every time I have raised one.

Hickory horned devil starting to eat its shed skin

Eating the shed skin, horns first

Over the next couple of hours, I checked on its progress as the larva slowly consumed the shed skin, starting with the formidable spines.

Hickory horned devil eating its shed skin

Almost done

By the next morning, Harvey had acquired his new set of colors, the bold green with stripes and the orange “horns” that cause people to worry (unnecessarily) about their safety should they encounter this behemoth.

HHD

Final instar of a hickory horned devil

Harvey then did what caterpillars do best – he ate and ate and produced a lot of rabbit  scat sized frass. He did this for another week (with a new group of admiring summer campers) and then the final change began. It starts with a blue-ish tint appearing in the green background color. Then he stopped feeding and began crawling about the cage, a sure sign that the search is on for a place to pupate (this species burrows into the soil to form its pupa).

hickory horned devil shrinking for pupation

Harvey shrinking and getting ready for the long sleep

Over the next couple of days Harvey started to shrink. By week’s end, he was about 1/3 his original size, but would still wriggle if touched.

Hickory horned devil approaching pupation

The day before the pupa

The last morning of camp, I looked in the container and the final shed had occurred, his old skin lying next to the fresh pupa.

Hickory horned devil  fresh pupa

Shortly after the last shed, the beginnings of a pupa (it darkens over time)

The pupa took a couple of days to harden and darken. Harvey will now wait until at least next summer (some overwinter as pupa for 2 years I have read) before emerging as a beautiful Royal Walnut Moth. Thanks, Harvey, for allowing two groups of summer campers (and some astonished adults) a glimpse into part of your amazing life.

Royal walnut moth

The final product (a Royal Walnut Moth)…next year