Trypoxylus dichotomus (Japanese Rhinoceros Beetle)
Formerly classified as Allomyrina dichotoma. A large horned beetle with a manageable larval period, and a great first rhino beetle.
About Trypoxylus dichotomus
Trypoxylus dichotomus (formerly classified as Allomyrina dichotoma) is one of the most popular rhinoceros beetles in the hobby. Native to East Asia (Japan, Korea, and China), it is widely captive-bred by European hobbyists. Males sport a distinctive forked cephalic horn and a shorter thoracic horn used in competition for mates. Adults are dark brown to reddish-brown and reach 40–80mm in length.
They are legal to keep in the UK and make an excellent introduction to Dynastinae (rhinoceros beetles) for keepers who have experience with flower beetles and want to try something larger.
Enclosure & substrate (larvae)
House larvae in individual containers with at least 2 litres of substrate per larva. Keep in a cool, dark location. Larvae are C-shaped grubs that feed on decaying wood.
You need flake soil (fermented hardwood sawdust). This is NOT the same as normal compost. Commercial beetle flake soil or kinshi (fermented oak) is recommended. Larvae will not thrive on generic compost. Replace substrate every 2–3 months as it becomes compacted with frass.
Adult enclosure & substrate
Adults need coconut fibre or organic compost, 10–15cm deep, to allow females to burrow and lay eggs. Provide bark for climbing and righting. Beetles that fall on their backs can struggle to turn over without something to grip.
Feeding
Larvae eat flake soil substrate only. No supplementary feeding is needed. Adults feed on beetle jelly, overripe banana, and other soft fruits. Beetle jelly is the cleanest and most convenient option, and widely available from invertebrate suppliers.
Lifecycle
Eggs hatch in 2–3 weeks. The larval period is 8–12 months, passing through three instars (L1, L2, L3). L3 larvae create a pupal cell from compacted substrate. Do NOT disturb at this stage. The pupal period lasts 3–6 weeks. Adults live 2–4 months.