The most popular and most known species in zoos are elephants, monkeys, big cats, penguins, crocodiles and similar larger animals, although there are approximately 5.500 mammal, 10.000 bird and 8.000 reptile species on Earth. However, described insect species are near 1 million! If zoos would like to educate visitors about biodiversity, they need to keep insects as well. Some insects are spectacular due to their size or colours and can be relatively easy to keep. One of them is the species from the genus Pachnoda.
What are Pachnodas?
Pachnoda is a genus of beetles (Coleoptera) in the subfamily of flower beetles (Cetoniinae). It contains about 120 species and more subspecies - described as species in some studies - so it might even contain more than 200 species. Pachnodas are native to Sub-Saharan Africa and live in varied habitats, mainly in tropical forests.
Imagoes measure around 20-25 mm. Most species are yellow with a black or brown pattern, but others can be green or orange. They can fly. Imagoes eat mainly pollen, flowers and fruits, while larvae are detritivores. Pachnodas reproduce sexually, parthenogenesis has not been described in this genus. These beetles develop by complete metamorphosis, so their life cycle consists of the egg, larva, pupa and the imago. Males and females are similar, the best method of sexing is to check the abdominal side of the abdomen, which has a smooth surface on females and a longitudinal groove on males.
How to keep your Pachnodas?
Because of their relatively small size they don’t need a large insectarium. For a small breeding group an approximately 50x50x50 cm sized terrarium is enough. For breeding it is most important to provide soil which needs to be minimum 12-15 cm deep. The soil can be mixed with the leaves of deciduous trees (60%), pieces of decaying wood (25%) and peat (15%). Keep it damp but not too wet, air humidity needs to be 70-80%. Air temperature is optimal between 25 and 28 °C (77 to 82 °F) and shouldn’t drop below 20 °C (68 °F). It can rise to 30 °C (86 °F), but never above 35 °C (95 °F). Pachnodas are diurnal and like strong light, but no UV lamp or other special light is necessary. At night beetles bury themselves into the soil. Mainly the males come to the surface at first, as females lay their eggs into the soil in the morning.
Larvae are detritivores therefore if the soil consists of leaves and decaying wood, they don’t need any other food. Imagoes eat fruits, flowers and pollen and their main diet in captivity consists of mixed fruits like bananas, apples, pears, oranges, kiwis, strawberries and other fruits. They like flowers such as lilacs, roses and locusts. As nutritional supplements they can be given glucose, pollen and honey. Avoid plants treated with pesticides, these could be lethal to Pachnodas.
On higher temperatures (28 to 30 °C; 82 to 86 °F) the life cycle is shorter, but imagoes have shorter lives than on lower temperatures (22 to 25 °C; 72 to 77 F). On optimal temperatures eggs hatch within two weeks, larvae develop within two months and flower beetles are in pupa stage for an additional two weeks. Imagoes live 4-6 months.
These are the principles of how to start keeping Pachnodas. I can encourage all zoos to keep this attractive and easy-to-keep insect species in their collection.