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Papilio glaucus (Iowa) Rearing Notes (May 28, 2019–May 31, 2019)

5/31/2019

Rearing notes for eastern tiger swallowtail (Papilio glaucus). Stock originated as F0 ("wild") eggs from Iowa, May 2019.

May 31

Around 40-50 more eggs hatched but, unfortunately, due to the heat of the climate chamber, many had already dessicated or were cannibalized, leaving only about 30 larvae left (shown above right). (Some larvae must have hatched close to 24 hours since we last checked and there was no food in the petri dish. This was a mistake.) We transferred all of these to fresh tuliptree leaves inserted in 5 ml tubes in clear plastic containers. Some began feeding immediately.
The older larvae (above left and middle) have generally grown rapidly, though there seems to be quite a bit of variably in growth rate. Some are already ready to molt to second instar, while a few are still very small for some reason.

May 30

Twelve more hatched.
The larvae that hatched yesterday seemed to have taken well to the tuliptree leaves.

May 29

Four eggs hatched. The larvae were all transferred to a young tuliptree (Liriodendron tulipifera) leaf, the same host we used for native Ithaca larvae last year. We are not what the preference for this host is for the Iowa population, but so far one of the larva has already fed a bit on the edge of the leaf. In Iowa, which represents westernmost range of glaucus, the larvae reportedly do well on hop tree (Ptelea), ash (Fraxinus), and Prunus, which, interestingly, are the typical P. multicaudata host plants.

May 28

We received approximately 80 F0 eggs from a supplier in Iowa. Most of these eggs have already reached the late stages of the yellow mottling phase. A few are partially black and may hatch tomorrow while a few also are green and therefore likely infertile. In addition, we noticed that some of the partially developed eggs had collapsed; this was not the case with the P. polyxenes asterius eggs we received in the same package. This is interesting because we have struggled with hatching glaucus-group eggs in particular in the past, namely, with P. rutulus. It may be that glaucus-group eggs are more susceptible to damage than machaon group eggs, perhaps owing to their differing ecology (glaucus-group eggs are laid on trees whereas machaon-group eggs are laid on forbs), though this is purely speculation.
It will be interesting to see how these differ from the local Ithacan glaucus, seeing as Iowa has a strong population of the mimicry model, Battus philenor. In Iowa, females are reportedly 95% the black form, whereas the local glaucus are predominantly yellow (personally, we have yet to see a black female at all). We shall see whether this is the case for ourselves when we rear these. There will likely be other differences in life history traits depending on what host plants are preferred in the respective localities and the climate. While the glaucus here are probably almost always obligately univoltine, the Iowa glaucus are said to be bivoltine, which is another way of saying they can be reared indefinitely without diapause under the right conditions. This will be advantageous for rearing a larger second generation of these eggs since pupae tend to die or have unreliable eclosion after a period of overwintering.

Brian Liang
Brian Liang is a student at Cornell University in Ithaca, New York pursuing an undergraduate degree in entomology. He is co-owner and a main contributor of the Liang Insects blog, insects articles, and site design.

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Papilio polyxenes asterius (Iowa) Rearing Notes (May 28, 2019–May 31, 2019)

5/31/2019

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Rearing notes for black swallowtail (Papilio polyxenes asterius). Stock originated as F0 ("wild") eggs from Iowa, May 2019.

May 31

The larvae on fennel are doing very well, growing mostly synchronously and ready to molt to second instar.
A few of the larvae on the artificial diet dessicated. The remaining appear to have fed based on the fact that they are still alive but they aren't too much larger than before. Hopefully they don’t dessicate and make better progress in the coming days.

May 30

Fifteen more larvae hatched. We transferred these to the fennel-based artificial diet that has been working with P. zelicaon. More information on the diet here.

May 29

About 40 of the eggs hatched. The larvae were transferred to a small cutting of fennel in a petri dish.
Like we have noticed with past experiences rearing this species, the newborn larvae are rather small and “delicate” (poor grip on host plant) with poorly developed white saddles compared to zelicaon larvae which are larger, more robust, with well defined, larger white saddles.

May 28

We received approximately 80 F0 eggs from a supplier in Iowa. Some of these eggs have already almost completed development and will likely hatch tomorrow. It will be interesting to see how these differ from the local Ithacan polyxenes, seeing as Iowa has a strong population of the mimicry model, Battus philenor. This is evidenced by that P. glaucus females in Iowa are reportedly 95% black, whereas the local glaucus are predominantly yellow (personally, we have yet to see a black female at all). There will likely be other differences in life history traits depending on what host plants are preferred in the respective localities and the climate. While we have yet to take note of the voltinism of the local polyxenes, it is almost certain that these Iowa types are strongly multivoltine.

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Papilio polyxenes asterius (Ithaca) Rearing Notes (May 27, 2019–May 31, 2019)

5/31/2019

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Rearing notes for black swallowtail (Papilio polyxenes asterius). Stock originated as eggs from Ithaca New York, May 2019.

May 31

A few of the eggs laid on the first day have hatched. All larvae were transferred to a cutting of fennel.
The female still surprisingly energetic and it managed to lay six more eggs.

May 30

The female laid almost 30 more eggs.

May 29

The female probably laid another dozen or two eggs (hard to tell since we never removed the old eggs from the cuttings) but has clearly begun to lose vigor.
We collected all the eggs from the cuttings in a petri dish and counted around 120 eggs, which is a fairly good amount for a single individual. Some of the older eggs already have a bit of brown on them.

May 28

The female laid around a hundred eggs, some of which were off the fennel cuttings, such as on the pyrex flask. This is far more eggs than the zelicaon laid earlier; there does seem to be a good correlation between how plump the female is and how many eggs it has. As we have noted in previous rearings, the eggs of polyxenes do appear to be smaller, on average, than zelicaon eggs so this could also be a factor in the average number of eggs a female can lay.

May 27

We found two fresh eggs, shown below, at Cornell Botanic Garden, one on caraway (Carum carvi) and one on dill (Anethum graveolens) sprouts growing next to the caraway. Around 5 p.m. we saw a pristine female fly into the garden that attempted to oviposit on the bronze fennel (Foeniculum vulgare “purpureum”) growing close by. As it stopped to oviposit, we captured it with a net.
Its abdomen is remarkably plump and the wings show no sign of damage. We suspect it could not have eclosed more than a few days ago, especially since the season is early. When we tried to feed it sugar water solution, it refused, perhaps because it was flustered and/or not hungry. For oviposition, we set it up in a small black popup cage in a climate chamber near white light with cuttings of bronze fennel in a flask. This is the same setup we used to get P. zelicaon to oviposit earlier this month.
More details here.

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Diadema inscriptum Rearing Notes (May 22, 2019–May 31, 2019)

5/31/2019

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Rearing notes for our lettered sphinx (Diadema inscriptum) larvae collected in Ithaca, New York, May 2018.

May 31

The fourth instar has become more vibrantly colored, with more visibly defined yellow stripes along the body. When disturbed, it not only arches its head back, but also regurgitates green fluid as well.
The first instars molted to second instar.

May 30

The fourth instar has dramatically increased its appetite.
The second instar molted to third instar.
The two first instars are now molting to second instar. One is slightly brown in color from feeding on the purplish new growth of the grape vine.

May 29

The third instar is molting to fourth instar. The dorsal side is now a much darker shade relative to the rest of the body and the horn is proportionally thicker and shorter.

May 28

The second and third instar larvae are both growing extremely quickly.
The two remaining eggs hatched.

May 27

The second instar molted to third instar. Nearly identical in appearance as the previous instar.
The first instar molted to first instar.

May 26

The second instar is molting to third instar and the first instar is molting to second instar.

May 25

The older larva molted to second instar and has already grown quite a bit. The dorsal side is becoming a slightly darker shade relative to the lateral sides. Just as we had observed last year, starting at this instar the larva folds its head back over its dorsal side when disturbed.
The larva that hatched yesterday has now become a more vibrant green after feeding.

May 24

One of the eggs hatched. The larva is pale greenish white with a short black horn.

May 23

The larva is now molting to second instar.

May 22

Found a first instar larva on grape and three eggs on creeper. The larva was resting on the vine of a new shoot and feeding on the buds and the three eggs were found on the upper and under side of young leaves.
This species has one of the earliest flights among the grape/creeper sphinx as they also appeared very early in the season last year, right after the vines started to grow in. They seem to have ovipositing preference for new shoots and buds.

Alan Liang
Alan Liang is a student at Cornell University in Ithaca, New York pursuing an undergraduate degree in entomology. He is co-owner and a main contributor of the Liang Insects blog and photographs.

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Papilio zelicaon Rearing Notes (May 28, 2019–May 30, 2019)

5/30/2019

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Rearing notes for anise swallowtail (Papilio zelicaon) larvae. Most are being fed fennel (Foeniculum vulgare), but a few were offered an artificial diet. Stock originated from Albany, California, Summer 2018.

May 30

A few of the larvae have molted to fifth instar.
The fourth instar larvae are about average sized or better from what we can recall from past rearings. They hover around 0.4 grams up to 0.5 grams after sampling a few individuals.
The third instar larvae on artificial diet seem to be growing faster than before as they become acclimated to the diet. Although larvae normally rest on their food, we notice that these larvae rest off the slice of artificial diet since there is not a lot of space on it. As a result, larvae often encounter and disturb each other which may be problematic. We would normally separate the different stage larvae into different dishes to mitigate larval conflict but in this case we did not since there are so few in total and we do not want to waste diet.

May 29

Many of the larvae are now fourth instar and have already grown quite lot. A few are already molting to fifth instar.
The larvae on artificial diet have survived yet another day feeding on it. The two largest ones have already molted to third instar and appear to be doing very well.

May 28

Some of the largest larvae have already entered fourth instar. For the most part they all became of the dark black phenotype just like when we used to rear them at home in California.
There are now only five larvae remaining on the artificial diet that all look quite healthy, especially two which are already molting to third instar. Of the original dozen or so larvae that we transferred onto the artificial diet, it seems the majority that survived (i.e. the five remaining) were the first few that were transferred. Perhaps mortality increased overtime as the diet became drier and firmer, making it harder for the new larvae to feed on it.

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First Hyalophora cecropia Pairings of the Year

5/29/2019

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Two of the three captive Hyalophora cecropia females we set outside paired with wild males last night. These are the first pairings of this year.

On the third night since we started setting captive females outside to call in wild males, we finally got pairings with two of the three females. The two females were the larger of the three, one of which eclosed three days ago that failed to call in a male the past two nights, and the other of which that just eclosed yesterday. Both also happened to be in the wire cage with larger holes (1 square inch) that we switched to last night since we suspected the cage with smaller holes (1/2 square inch) that we used the past two nights was physically preventing males from copulating with the female. The female that failed to pair was the smallest of the three and was in the cage with smaller holes. This suggests that our suspicion was perhaps correct, though sample size is small and it could be a coincidence. Either way, though, we'd rather play it safe and use the one with larger holes from now on, even if there is a small risk smaller individuals could escape.

The wild males in the pairings were still paired with the females long after the sun rose and remained coupled until dawn. Like we observed last year with the wild males called in, they are extremely large compared to our captive males and even a bit larger than the females. Alas, growth in the wild must be much superior to captive, crowded, conditions even when reared in sleeves. In addition, the males have darker, more contrasting colors, with a darker gray ground color, crisper white and red margins, and darker red body. This differs from our captive individuals (both male and female), which tend to have a lighter grey ground color that is infused with more white and yellow scales and have lighter red bodies. We noticed the same thing last year and weren't sure if it were genetic or environmental. We are starting to suspect it is more environmental at this point, since the males from last year and this year have been consistently this darker phenotype. Perhaps the temperature and humidity that the cocoons diapaused or developed under affected the coloration? Not sure if we would ever know for sure but it's an interesting to note.

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Papilio rutulus Rearing Notes (May 1, 2019–May 29, 2019)

5/29/2019

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Rearing notes for western tiger swallowtail (Papilio rutulus) pupae. Stock originated from a single pairing between reared female and wild male in Albany, California, Summer 2017; currently in third generation.

May 29

A male eclosed; it is rather small and has a slightly wrinkled hindwing perhaps from falling down when expanding its wings.
Since we are not sure if a female will eclose from the remaining pupae any time soon, we took it out of the climate chamber, fed it, and placed it in a plastic box for now. If no female comes out, there is still the possibility of hybridizing this male with the female P. glaucus that eclosed today, but only as a last resort….

May 28

At last, one of the pupa has finally begun to show signs of development, turning yellow and black. It truly is a mystery why Papilio pupae, especially this species, eclose seemingly randomly and rarely synchronously. Nonetheless, the fact that one is about to eclose gives us hope that perhaps others will eventually, as they are clearly alive.

May 3

We brought the pupae to the climate chamber (27 °C, 75% humidity) to aid in breaking diapause. Pupae were hung upside down in a mesh pop up cage.

May 1

Took diapausing pupae out of refrigerator; all appear to be alive.

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Papilio glaucus Rearing Notes (May 1, 2019–May 29, 2019)

5/29/2019

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Rearing notes for eastern tiger swallowtail (Papilio glaucus) pupae. Stock originated from wild eggs or larvae collected in Ithaca, New York, Summer 2018.

May 29

To our surprise, a pristine, moderately sized yellow form female eclosed today. It has fairly thick black stripes with a moderate amount of blue on its hindwings.
Since we are not sure if a male will eclose from the two remaining pupae or if we’ll be able to caught one in the wild any time soon, we took it out of the climate chamber, fed it, and placed it in a plastic box for now. If we really can’t obtain a male glaucus, there is still the possibility of hybridizing this female with the male P. rutulus that eclosed today, but only as a last resort….

May 28

After all the failed eclosions and deaths, only three pupae remain. Today we checked again and it appears one of them is fully developed. Hopefully it won’t result in another failed eclosion.

May 22

A yellow form female eclosed but unfortunately was crippled just like the male.
For reasons that we still have not yet realized, the eclosion success rate for the glaucus-group has been extremely poor for us, especially with post diapausing individuals. Butterflies either emerge crippled or fail to do so at all despite being fully developed. We are not sure if it has anything to do with the environment (i.e. perhaps the climate chamber is too hot), or if they dried out during the overwintering process?

May 19

Unfortunately it seems that the butterflies that were going to eclose may have died in the pupal shell before eclosing for some reason as they have not come out after a full day.

May 18

Two pupa are now showing clear signs of development despite the long wait! Hopefully the rest start budging so there will be a chance of obtaining a pairing.

May 16

A male eclosed but was crippled. Strangely, none of the other pupae appear to be developing despite how many days it has been?

May 3

We brought the pupae to the climate chamber (27 °C, 75% humidity) to aid in breaking diapause. Pupae were hung upside down in a mesh pop up cage.

May 1

Took diapausing pupae out of refrigerator; all appear to be alive.

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Received Iowa Papilio glaucus & Papilio polyxenes asterius Eggs

5/28/2019

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We received eastern tiger swallowtail (Papilio glaucus) and black swallowtail (Papilio polyxenes asterius) eggs from Iowa. The state of the eggs and potential differences between Iowa and local populations of the two species is speculated upon and discussed.

We received approximately 80 F0 ("wild") eggs each of Papilio glaucus and P. polyxenes asterius from a supplier in Iowa. The glaucus eggs are shown below:

Most of these glaucus eggs have already reached the late stages of the yellow mottling phase. A few are partially black and may hatch tomorrow while a few also are green and therefore likely infertile. In addition, we noticed that some of the partially developed eggs had collapsed; this was not the case with the P. polyxenes asterius eggs, which were received in the same package. This is interesting because we have struggled with hatching glaucus-group eggs in particular in the past, namely, with P. rutulus but rarely with those of machaon-group species. It may be that glaucus-group eggs are inherently more susceptible to damage than machaon-group eggs, perhaps owing to their differing ecology (glaucus-group eggs are laid on trees whereas machaon-group eggs are laid on forbs), though this is purely speculation.

The polyxenes eggs, shown below, are in excellent shape, for the most part. They seem to be much more varied in age than the glaucus though. Some of the eggs have already almost completed development and will likely hatch tomorrow.

It will be interesting to see how these differ from the local, Ithaca populations of these species seeing as Iowa has a strong population of the mimicry model, Battus philenor, which is absent in Upstate New York. In Iowa, female glaucus are reportedly 95% the black form, whereas the local glaucus are predominantly yellow (personally, we have yet to see a black female at all). We shall see whether this is the case for ourselves when we rear the glaucus eggs. As for polyxenes, we have recently noted how the wild female that we captured yesterday had a substantial amount of yellow scales, which should be undesirable in mimetic selection, so we are interested to know how the Iowa adults turn out. There will likely be other differences in life history traits between the populations of both species depending on what host plants are preferred in the respective localities and the climate. While the glaucus here are probably almost always obligately univoltine, the Iowa glaucus are said to be bivoltine, which is another way of saying they can be reared indefinitely without diapause under the right conditions. This will be advantageous for rearing a larger second generation of these eggs since pupae tend to die or have unreliable eclosion after a period of overwintering. While we have yet to take note of the voltinism of the local polyxenes, it is almost certain that these Iowa types are strongly multivoltine.

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Hyalophora cecropia Rearing Notes (May 1, 2019–May 28, 2019)

5/28/2019

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Rearing notes for our cecropia moths (Hyalophora cecropia). Stock originated as eggs from New York, June 2016.

May 28

Two more females eclosed, one moderately sized one mid-morning and a very small one early afternoon. Both are smaller than the first female and slightly darker in coloration.
The female set outside failed to call in male for the second night in a row. We still suspect that we have just been getting unlucky due to low density of wild males at this time and perhaps the holes in the cage are too small for the male. Thus, tonight we placed the first female and the larger of the two new females in the wire cage we used last year (1 square inch holes) and set it in the same location as last night. Since the smaller female would probably be able to escape from this cage if it got agitated, we put it in one of the cages we made this year (½ square inch holes) and set it along the edge of the trail.

May 27

Unfortunately, the female failed to call in a male. A simple explanation for this could be that there is still only a low density of wild males in flight right now and we got unlucky? In that case we would just have to keep putting the female out and a male should come eventually. However, other reasons could be that the location was not ideal or the cage’s small holes made it difficult for the male’s abdomen to physically reach the female's. In the former case, we could try varying the location each night. The latter possibility, though, would actually be quite problematic if it really was the case, and it would be hard to tell if it was. For now we decided to stick with the same cage and give it another try. This time we placed the female along the middle the Cascadilla Gorge Trail rather than along the periphery.
Another male eclosed early morning. This one is the smallest of the five by far.

May 26

Two males eclosed mid-morning. Both are on the smaller size and look quite similar phenotypically as the first two (as expected since they’re siblings).
At last, a female eclosed early afternoon. It is significantly larger than any of the four males with more rounder forewing shape and a large, round abdomen. Like last year, we plan to outcross the captive females by calling in wild males to start this year’s generation. The wild population should be in flight already based on when we obtained last year’s pairings.
In the late evening, the female was placed in a self-crafted wire cage (a piece of wire mesh with ½ square inch holes rolled into a cylinder with a pan as a lid) and set outside on the outer edge of Cascadilla Gorge Trail, near the same locality we obtained pairings last year.

May 25

Another male eclosed, again in mid-morning. It is a bit smaller compared to the first one and darker in color.
It is quite unusual that only two have eclosed so far and with a four day gap. The remaining cocoons seem to be alive but for some reason are taking quite a while to eclose.

May 21

A male eclosed mid-morning. It is moderately sized with relatively pale wings, similar to individuals we reared last year (parental generation).

May 18

A naked male pupae appears to be quite developed already. We anticipate eclosions to begin in the next week.

May 14

Found a dead cocoon near the black cherry tree at Beebe Lake that we sleeved the caterpillars last summer. Assuming it was an escapee that got parasitized (?) like the one we found on 3/30/19.

May 1

Took diapausing cocoons out of refrigerator; assuming most are alive based on how they “feel” when rattled, though there are certainly at least a few dead based on foul smell. Cocoons were placed on damp paper towels at the bottom of a mesh pop up cage at room temperature. The weather is now consistently warm and the leaves of most trees are beginning to grow in. We anticipate eclosions in late May, which we believe should correspond with the flight of the wild population.

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