Attacus atlas rearing notes

A summary of my ongoing experiences while rearing Attacus atlas. They are being reared indoors on Ligustrum lucidum (tree privet) that is replenished daily and treated with a hydrogen peroxide rinse to reduce chances of infection. Since emergence, the larvae have been exposed to 9 hour photoperiods under 2 45W incandescent lamps.

OCTOBER 1, 2021: A cohort of 57 Attacus atlas eggs of undisclosed origin arrived. They were placed in a dry, airtight plastic container with a paper towel at the bottom. (The temperature ranged from 68-72*F. Humidity was near zero.)

October 7, 2021: The first group of larvae emerged in the evening. They were provided with a sprig of Ligustrum lucidum but did not begin eating immediately, as is typical with many Saturniidae larvae. Their enclosure remained airtight to maintain humidity. (Temperature: 68-72*F, humidity: 90%+.)

OCTOBER 8, 2021: The rest of the larvae had emerged by morning and had begun eating the privet. 2 additional sprigs were cleaned and added into the enclosure. Each sprigs' end was wrapped in a small, moist piece of paper towel and tin foil for hydration. (Temperature: 66-72*F, humidity: 90%+.)


L1 larvae

OCTOBER 8-13, 2021: There were no deaths during this period. I changed their food every 24 hours and replaced their paper towel and cleaned their enclosure with a rinse of H2O2 every 12 hours. Humidity was kept at 90%+ to prevent desiccation, so I was being obsessively sanitary, hence the hydrogen peroxide. (Temperature: 66-72*F.)

October 14, 2021: Several (13) L1 larvae entered apolysis. Everything else proceeded as usual. (Temperature: 66-71*F, humidity: 90%, mortality: 0.)

October 15, 2021: Most (53) of the larvae had entered apolysis and the first 2 successfully ecdysed into the second instar. Everything else continued as usual. (Temperature: 67-72*F, humidity: 90%+, mortality: 2)


L2 larvae

October 16, 2021: Only 4 additional larvae ecdysed into the second instar, the rest remained in apolysis. There was very little eating that day. (Temperature: 67-72*F, humidity: 90%+, mortality: 1)

OCTOBER 17, 2021: 1 larva ecdysed into the second instar. Seven larvae underwent a failed ecdysis. Their head capsules popped off but they were seemingly unable to slough off their skins. In some cases, the fresh prolegs of the new instar could be seen protruding from the dried skin. The larvae that failed ecdysis were dispatched, as they were completely incapacitated by their old skins. (Temperature: 68-73*F, humidity: 90%+, mortality: 7, remaining larvae: 47.)

OCTOBER 18, 2021: 5 larvae ecdysed into the second instar. 11 underwent failed ecdysis and died. The second instar larvae displayed no signs of infection and continued to behave normally. (Temperature: 66-72*F, humidity: 90+%, mortality: 10, remaining larvae: 36.)

Sorry for the huge delay with updates, I've been a bit busy lately. I'll finish this post off with a more condensed recollection and analysis.

Around October 20th I had 16 larvae left because the rest had failed ecdysis, most likely due to the cold. A few (7) molted into L3.


young L3 larva

One larva became infected and I moved the rest to a net enclosure to give them some space, but more started becoming diseased so I resigned myself to raiding target for some small 6x3x3 tupperwares. At this point there were 8 remaining larvae that I separated into individual containers, cleaning each meticulously. The larvae were all now L3.


developed L3 larva

Disease took 5 more larvae by the end of October but the quarantine had managed to mitigate the spread, so I was left with 3 healthy late L3 larvae. I changed their food ant towels daily, rinsing their containers with a diluted H202 solution.

On November 1st the first larva molted successfully into the fourth instar but it was surprisingly small; barely 1.5 inches in length. It was at this point that the larva developed the signature turquoise hue of the atlas larva, as well as extended scoli. The orange abdominal patches were no longer present.


young L4 larva

On November 2, the first L4 larva got sick and died. The two remaining larvae shed into L4 in the following days. Those two made it to pupation.

From November 9th onward, the last 2 larvae ate constantly and developed well, reaching a large size of 5 inches in length at L6. I kept a heat lamp over their enclosures in addition to the light to encourage faster development. The plastic lids had only a few air-holes so humidity was at 99% percent most of the time, though that was of little concern to me because these larvae were living in completely isolated, obsessively maintenanced habitats. The smaller larva did experience a failed ecdysis but I managed to pull the skin off before it was too late. They ate about a dozen leaves a day.


left: young L5 larva, right: developed L5 larva with prominent scoli

They developed a thin powdery wax substance on their skin common on many attacini larvae and were very strong when gripping to my hand. Their coloration developed into a softer greenish-blue and they developed small light spotting patterns. The waxy substance seemed more concentrated on the dorsal scoli of the larva rather than the skin.


L6 larvae

By December 1 both larvae entered apolysis for the final time and were placed in pupation chambers. By the 4th, they had pupated and were kept under the heat lamp.


Pupa

One pupa collapsed into itself the day after it pupated and died, so I was left with only one.

I foolishly took it out of the container and placed it in a heated net-enclosure in a room with a humidifier, thinking these devices would create a sufficiently hot/humid environment until it emerged. The pupa eventually desiccated and died despite this.

Regardless of wether or not I got to witness a live adult, I did experience (amongst multiple individuals), the majority of the life cycle of this remarkable creature and am happy for having done so.

If I were to give it another attempt, I would rear them in the summer where the temperature isn't such an important variable to constant have to manage, as I believe low temperature may have been the underlying cause of many issues related to failed ecdysis (poor liquid diffusion) and stress (lowered rate of consumption), the latter leading to increased risk for disease. I would also separate them into many cohorts as soon as they hatched to mitigate infection. It would be a lot of work, but with a species as unpredictable as this I wouldn't leave anything up to chance. Hopefully this journal post helps to impart some useful and saving knowledge to anyone wishing to rear this awesome species.

Cheers!

הועלה ב-אוקטובר 22, 2021 12:00 לפנה"צ על ידי crake crake

תגובות

Hello Oliver, thank you for sharing this. May I ask whether you were successful in raising to adults and if so, how many did survive?
I raised Attacus lorquinii from eggs and recognize the problems with skin shedding as you described above. I managed to manually remove the dried skin where it hampered the movements. The caterpillars did fine after that and continued to grow.
Kind regards, Michaela

פורסם על-ידי michaela לפני בערך 2 שנים

@michaela, thanks for the comment. Sorry those rearing notes ended so abruptly, I actually did get 2 larvae to pupation. The rest of the larvae succumbed to failed ecdysis and/or disease, so during the 3rd instar, I transferred 8 larvae to individual plastic containers with high humidity and temperature (approx. 80*F). 3 larvae lasted into the fourth instar and 2 into the fifth and sixth. They both pupated successfully but died before emerging. The only possible explanations I have for that are either disease or poor genetics. I would not recommend rearing them during winter as there are too many variables that can fall out of control, but regardless, rearing these animals was a rewarding experience!

I'll take some time and update the journal according to the notes I wrote down.

פורסם על-ידי crake לפני בערך 2 שנים

Our hatching result was two females and three males from 53 eggs though all eggs hatched within two days. Another two pupa were attacked and eaten by ants, and two did not completely develop. I also noticed a time difference of two weeks between the first and the last emergence.
Temperature was not much of an issue here in the Philippines. They were kept in an enclosure made of old screen doors. That worked very well since we could cover it when there was too much rain. The food source was calamansi leaves. I should write a post .... though it would not be as detailed as yours! Thanks again for sharing.

פורסם על-ידי michaela לפני בערך 2 שנים

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