Source: Wikimedia Commons
Neptune Beetle
AdvancedRare large beetle from South American highlands. Second largest after Hercules. Jet-black body with long horn is stunning.
Difficulty
Advanced
Temperature
20〜28℃
Lifespan
Adult 6-12 months, larva 2-3 years
Size
Up to 150mm
Humidity
60〜80%
Diet
Beetle jelly (adult), fermented substrate (larva)
About
Dynastes neptunus, the Neptune beetle, inhabits high-altitude cloud forests of the Andes in Colombia, Ecuador, and Peru, at elevations roughly between 1,000 and 2,500 meters. It is one of the largest rhinoceros beetles, with males reaching total lengths of 80–150 mm, ranking second only to the Hercules beetle in maximum size. Males bear a long thoracic horn and shorter cephalic horn, with a striking glossy jet-black body coloration. As a highland species, it requires strict low-temperature management at 17–22°C; warmer conditions are detrimental to both adults and larvae. The larval stage spans 2–3 years—exceptionally long for a rhinoceros beetle—and demands large quantities of high-quality fermented substrate. Females lay eggs in fermented substrate, and breeding is moderately challenging. Adults live 6–12 months. While requiring experienced husbandry, the Neptune beetle's jet-black form and impressive proportions make it one of the most revered species in the collecting world.
Basic Info
Origin
high-altitude Andean cloud forests of Colombia, Ecuador, and Peru
Lifespan
Adult 6-12 months, larva 2-3 years
Size
Up to 150mm
Temperature
20〜28℃
Humidity
60〜80%
Diet
Beetle jelly (adult), fermented substrate (larva)
Care Guide
Temperature
17-22°C (cool temperature essential)
Larval period
2-3 years — very long
Rarity
Rare in trade and expensive
Environment
Wine cooler temperature management essential
Notes
Highland species — Japanese summer is biggest threat
RareJet-blackSouth American highlandLarge
Neptune Beetle FAQ
QHow difficult is it to keep Neptune Beetle?
A
Advanced. This is an advanced-level species. It requires specialized equipment and advanced husbandry skills with precise environmental control.
QWhat is the ideal temperature for Neptune Beetle?
A
The ideal temperature for Neptune Beetle is 20〜28℃. Recommended humidity is 60〜80%. Avoid sudden temperature changes and maintain a stable environment.
QWhat is the lifespan of Neptune Beetle?
A
The average lifespan of Neptune Beetle is Adult 6-12 months, larva 2-3 years. With proper care and nutrition, they can live a long and healthy life.
QHow large does Neptune Beetle get?
A
Neptune Beetle typically reaches Up to 150mm as an adult. Size may vary depending on care conditions and individual genetics.
QWhat should I feed Neptune Beetle?
A
Neptune Beetle feeds on: Beetle jelly (adult), fermented substrate (larva). Aim for a balanced diet with appropriate feeding frequency.
QWhat is the typical price for Neptune Beetle?
A
The price of Neptune Beetle varies significantly depending on morph, size, and lineage. Check our market price page for the latest pricing information.
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