🐛 Life Cycle of Muga Silkworm (Antheraea assamensis)

Life cycle of Muga Silk worm

The Muga silkworm, scientifically known as Antheraea assamensis, is a semi-domesticated, non-mulberry silk-producing insect that undergoes a complete metamorphosis in four stages: Egg, Larva, Pupa, and Adult Moth. Muga silkworm produces Muga silk, exclusive to Assam, India, is one of the world’s most luxurious and naturally golden silks.

🥚 Stage 1: Egg Stage

The Muga silkworm life cycle begins when the female moth lays 150–200 oval-shaped, pale-yellow eggs, mostly on the leaves of Som (Persea bombycina) and Soalu (Litsea polyantha) trees. The eggs are 1–1.2 mm in diameter. They are laid at night and hatch in 9–12 days. The Temperature and humidity play a vital role in egg viability. It has two Peak seasons: Jethua crop (May–June) and Kotia crop (October–November)

🐛 Stage 2: Larva (Caterpillar) Stage

After hatching, larvae begin feeding on tender host leaves. This is the longest stage in the life cycle, lasting around 30–35 days, during which the larva undergoes five molting stages (instars).

🔸 Instar Breakdown:

1. 1st–2nd instar: Tiny, dark-colored larvae

2. 3rd–4th instar: Greenish-yellow body with increased size

3. 5th instar: Large, bright green body with prominent white lateral lines

🍃 Feeding Insight:

Main diet: Som and Soalu leaves

Leaf quality affects cocoon size and silk yield

Requires a clean, pest-free environment for healthy development

🐚 Stage 3: Pupa (Cocoon) Stage

Mature larvae spin golden-yellow cocoons, where they pupate and transform into adult moths. This stage lasts 15–20 days. The cocoon is oval, compact and golden-hued. Muga silk is often harvested after the moth emerges to ensure cruelty-free practices (Ahimsa silk). Cocoon weight and density determine silk filament length. A well-fed larva yields a heavier, silk-rich cocoon

🦋 Stage 4: Adult Moth Stage

The adult moth emerges from the cocoon using an enzyme that softens the cocoon shell. These moths are cream to brown in color, with beautiful eyespots on their wings. It has 10-12cm long wings. Their life span is very short only 5-7 days. They do not feed as their mouthparts are vestigial. Their mating begins soon after emergence. Mating occurs during dusk or night, ensuring timely egg-laying

Summary of Life Cycle Duration

Stage	Duration (approx.)	Key Activity
Egg	9–12 days	Embryonic development
Larva	30–35 days	Feeding, molting
Pupa	15–20 days	Metamorphosis in cocoon
Adult Moth	5–7 days	Mating, egg laying

The life cycle of the Muga silkworm is not just a fascinating biological process—it’s also a living symbol of Assamese culture, biodiversity and sustainable textile production. Understanding each stage in detail helps improve sericulture outcomes and supports eco-friendly practices in the silk industry.

📚 References

1. Sengupta, K., & Dutta, R. N. (1992). Recent Advances in Sericulture. Central Silk Board, Bangalore.

2. Jolly, M. S., Sen, S. K., Sonwalkar, T. N., & Prasad, G. K. (1979). Non-Mulberry Sericulture. FAO Agriculture Services Bulletin.

3. Thangavelu, K. (1991). Handbook of Sericulture: Technologies and Applications. Oxford & IBH Publishing.

4. Narasimhanna, M. N. (1988). Manual of Silkworm Egg Production. Central Silk Board.

5. Chakravorty, R., & Neog, K. (2011). “Sericulture and Its Prospects in Assam.” Indian Silk Journal.