Parent body length: Male 62.37mm / Female 45.02mm
Number of eggs laid: 33 eggs
Incubation period of eggs: Approximately 6 months
Substrate used for laying: LB Flake Soil (substrate fermented twice)
Survival rate from hatching to L2: Approximately 30%
Substrate used for larvae: LB Flake Soil (substrate fermented twice with Kinshi)
Amount of flake soil used per larva: 8.4L (2.2 gallons)
Larval period: Approximately 10 months
Pupal period: 30-45 days
Inactive periods: 20-30 days
Maturity period: 15-20 days after inactive periods
Life span of adult: 3-5 months (can live a little longer if not paired)
✅ Eggs:
Dynastes grantii is infamous for its long egg incubation period. While in some cases the eggs may hatch within a month depending on temperature and humidity, it usually takes around 3 to 6 months, and in the worst cases, up to a full year.
The reason for the extremely low survival rate from hatching to L2 is often due to the parents being wild-caught(WD). Wild adults always carry red mites, which hide under the elytra and are nearly impossible to fully remove.
The real issue is that these mites can eat eggs, which is especially devastating given the species' long incubation time.
I’m hoping that the next generation will show better hatch rates.
04/22/2024
The outline of the larva has started to become visible inside the egg.
✅ Larvae:
The larval period for Dynastes grantii is generally known to be around 10–14 months.
I raised my larvae using my own LB Flake Soil, and each larva consumed 8.4 liters (2.2 gallons) of substrate.
▪ Egg to L1: 160ml (5.5oz)
▪ L2: 350ml (12oz)
▪ Early L3: 1000ml (34oz)
▪ Mid to late L3: 2300ml (78oz) × 3 rounds
As for weight, the heaviest male reached 48g, and the largest female reached 31g.
06/04/2024
Newly Hatched Larva from Egg.
11/05/2024
5 Months After Hatching (Male / Left)
12/24/2024
7 Months After Hatching (Female / Right)
03/23/2025
10 Months After Hatching (Male)
✅ Pupa:
The pupal period ranged from a minimum of 29 days to a maximum of 48 days.
The heaviest male pupa weighed in at 38g, while the heaviest female reached 26g. This represents roughly a 20–25% reduction from their final larval weights.
04/23/2025
Male Pupa
04/13/2025
Female Pupa
✅ Adult:
All three males that recently emerged showed signs of eclosion failure, particularly with wing deformities. I spent some time reflecting on what might have gone wrong, and two possible causes.
1. Exceeding individual growth potential.
As the saying goes, “Big parents produce big offspring,” but there’s always an upper limit to an individual’s potential.
In the wild, D. grantii rarely exceeds 70mm, so producing offspring over 80mm likely means they’ve grown beyond their natural capacity, probably due to the high nutritional content of the flake soil I provided.
When this happens, the abdomen can become disproportionately large, leading to improper folding of the hindwings or an inability to close the elytra properly.
There are similar reports with D. hercules hercules, only about 20–30% of larvae that exceed 140g weight manage to complete eclosion cleanly.
This kind of mismatch between nutrition and physiological limits is not uncommon in captive breeding and tends to improve gradually over generations. So, I’m not overly worried at this stage.
2. Poor-quality floral foam
I recently noticed that the floral foam I newly purchased absorbs significantly less moisture than previous products. This could potentially cause eclosion failure in individuals that release a large amount of bodily fluid during eclosion.
The current Guinness record for D. grantii stands at 89.1mm.
I couldn't break it this time, but the largest male of my LBDG WF1 breed was 86.1mm and the largest female was 57.1mm.
So, I hope the next generation has a real shot at breaking the record.
LBDG WF1 - 1 ♂ (Left)
84.06mm
LBDG WF1 - 2 ♂ (Right)
80.65mm
📌 Due to an abnormally swollen abdomen and deformed elytra, it was unable to properly fold its hindwings.
I ended up trimming the hindwings, but unfortunately, it still died just two weeks after eclosion.
LBDG WF1 - 3 ♂
86.14mm
📌 This male, with a final larval weight of 48g and a pupal weight of 38g, was the most promising of the group.
However, just like LBDG WF1-2, he ended up with an abnormally swollen abdomen and deformed elytra, which prevented proper folding of the hindwings and even kept the elytra from fully closing.
Thankfully, despite these issues, he has managed to survive for over 20 days instinctively tearing off the unnecessary hindwings himself.
With a bit of luck, he might still be able to pair successfully.
LBDG WF1 - 4 ♀ ????
59.37mm
📌 The last D. grantii larva that had exceeded 37g in weight finally emerged about a week ago.
Normally, large female larvae weigh around 30-32g, and 37g is the kind of weight where you’d expect a male to reach the mid-to-upper 70mm range. So, I assumed it would turn out to be a male.
But instead, a monstrous-sized female has emerged.
What’s fascinating is that, despite both parents being wild-caught specimens, she has turned out to be an exceptionally clean specimen with no spotting at all.
The female that emerged just before her was also nearly spotless, but this one is especially stunning.
LBDG WF1 - 5 ♀ (Left)
55.71mm
LBDG WF1 - 6 ♀ (Right)
55.16mm
LBDG WF1 - 7 ♀ (Left)
56.40mm
LBDG WF1 - 8 ♀ (Right)
56.91mm
LBDG WF1 - 9 ♀
57.13mm
LBDG WF1 - 10 ♀
56.19mm
📌 Successfully emerged as an adult on June 12th.
She turned out incredibly clean and flawless