Chelorrhina polyphemus
An iridescent flower beetle from tropical Africa — vivid green with purple flashes, and a rewarding intermediate species.
About Chelorrhina polyphemus
Chelorrhina polyphemus is a large cetoniine beetle from Central and West Africa. Adults reach 40–60mm and display brilliant iridescent green colouration with purple or coppery highlights — the structural colour shifts depending on viewing angle. Males have a distinctive Y-shaped cephalic horn.
They sit between Pachnoda and Mecynorrhina in terms of difficulty. If you have raised Pachnoda successfully, Chelorrhina is a natural next step — the larvae are bigger and need more care, but the principles are similar.
Larval care
Larvae feed on fermented hardwood flake soil. As a cetoniine species, they process white-rotted deciduous wood — standard compost will not sustain them properly.
- Provide 2–3 litres of flake soil per larva
- House individually or in small groups with ample space
- Replace substrate every 2–3 months as frass builds up
- Keep substrate moist but not sodden
- Temperature consistency matters — avoid fluctuations below 22°C
L3 larvae construct a solid pupal cocoon from substrate and frass. This cocoon is critical — if it is broken or cracked, the pupa will almost certainly die or emerge deformed. Leave the container undisturbed once feeding stops.
Adult enclosure & feeding
Adults need a warm, ventilated enclosure with bark for climbing and a shallow dish for food. Provide 8–10cm of coconut fibre substrate. These beetles are active flyers, so a secure lid is essential.
Adults feed on beetle jelly and soft ripe fruit — banana, mango, and fig work well. They also readily visit flower petals (roses, hibiscus). Replace food every 1–2 days.
Breeding
Females burrow into moist flake soil to lay eggs. Provide 15–20cm of substrate depth for egg-laying. Eggs hatch in 2–3 weeks. A female typically produces 15–30 eggs. Separate L2 larvae into individual containers if you want to maximise adult size.