Source: Wikimedia Commons
Rainbow Stag Beetle
BeginnerPhalacrognathus muelleri
The world's most beautiful stag beetle from Australia. Iridescent metallic rainbow body is its defining trait. Docile and easy to keep. Larvae thrive on both fungus bottles and substrate.
Difficulty
Beginner
Temperature
20〜26℃
Lifespan
Adult 1-2 years / Larva ~8 months
Size
30-70mm
Humidity
60〜80%
Diet
Jelly (adult) / Fungus bottle or fermented substrate (larva)
About
Phalacrognathus muelleri, the rainbow stag beetle, is the sole species in its genus and belongs to the family Lucanidae. Native to the rainforests of northern Queensland, Australia, and New Guinea, it is celebrated for its remarkable iridescent coloration, appearing in red, green, blue, or black forms depending on the individual. Adults reach 30–65 mm in length and inhabit tropical forest canopies, feeding on tree sap and fruit. In captivity, small to medium enclosures are suitable, furnished with pieces of bark and wood to prevent toppling. Egg-laying occurs directly in fine-particle fermented substrate packed to a depth of at least 10 cm. Optimal temperature is 20–25°C, and adults live one to two years—an unusually long lifespan for stag beetles. Its spectacular coloration, manageable size, and straightforward husbandry make it one of the most sought-after display beetles worldwide.
Source: Wikipedia (CC BY-SA 4.0)
Basic Info
Origin
northern Queensland, Australia and New Guinea
Lifespan
Adult 1-2 years / Larva ~8 months
Size
30-70mm
Temperature
20〜26℃
Humidity
60〜80%
Diet
Jelly (adult) / Fungus bottle or fermented substrate (larva)
Care Guide
Enclosure
Small-medium case. Add plenty of bark to prevent flipping
Breeding
Lays in substrate. Pack fine fermented mat deeply
Larva Care
Both fungus bottles and substrate work. Temperature is key to size
Notes
Adults take 2-3 months before starting to feed after eclosion
Beginner-friendlyExoticBeautifulEasy keeping
Rainbow Stag Beetle FAQ
QHow difficult is it to keep Rainbow Stag Beetle?
A
Beginner. This is a beginner-friendly species. No special equipment or experience is required, and it can be kept successfully with basic care setup.
QWhat is the ideal temperature for Rainbow Stag Beetle?
A
The ideal temperature for Rainbow Stag Beetle is 20〜26℃. Recommended humidity is 60〜80%. Avoid sudden temperature changes and maintain a stable environment.
QWhat is the lifespan of Rainbow Stag Beetle?
A
The average lifespan of Rainbow Stag Beetle is Adult 1-2 years / Larva ~8 months. With proper care and nutrition, they can live a long and healthy life.
QHow large does Rainbow Stag Beetle get?
A
Rainbow Stag Beetle typically reaches 30-70mm as an adult. Size may vary depending on care conditions and individual genetics.
QWhat should I feed Rainbow Stag Beetle?
A
Rainbow Stag Beetle feeds on: Jelly (adult) / Fungus bottle or fermented substrate (larva). Aim for a balanced diet with appropriate feeding frequency.
QWhat is the typical price for Rainbow Stag Beetle?
A
The price of Rainbow Stag Beetle varies significantly depending on morph, size, and lineage. Check our market price page for the latest pricing information.
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