HKBIH - Beetles

Beetles, members of the order Coleoptera, are one of the most taxonomically and functionally diverse groups of organisms among insects, or even all animals. Including families of worldwide distribution, beetles account for more than a quarter of all currently known animal species and many play vital roles in their ecosystems. Hong Kong has recorded to date more than a thousand species of beetles from over 90 families. Even so, more are yet to be discovered.

Beetles come in a seemingly infinite variety of sizes, shapes and colours. Longhorn beetles can be hundreds of times the size of some minuscule featherwing beetles, which are of similar size to the full stop of this sentence. Like chafers, buprestids and leaf beetles, many are living jewels that shine with iridescent, metallic lustre. Their antennae also vary greatly and can be any from serrated, beaded, clubbed, layered to comb-like.

Thriving in nearly every terrestrial and freshwater habitat, beetles occur from tropical rainforests to polar tundra, deserts to rivers, coasts to mountaintops, countryside to cities, where they dwell in soil, tree barks, cowpats or even household cupboards. Their successful inhabitation of such a staggering spectrum of habitats depends on appropriate adaptations at every stage of their life: egg, larva, pupa and adult. Beetles are typically characterised by a pair of elytra, the hardened forewings that protect the membranous hindwings and soft abdomen. Of the attributes that underpin the successful radiation of this taxon, the elytra protect beetles against unfavourable environments and serve as an important trait facilitating their adaptation.

Fireflies

Fireflies are unquestionably one of the flashiest beetles. Hong Kong's diverse habitats are home to some 30 firefly species, from mangroves in Inner Deep Bay to abandoned fields adjoining villages, open shrublands at taller summits to woodlands and streams below the hills. Many of these fireflies have specific habitat requirements and thus exhibit various behaviours.

Fireflies always call to mind scorching summertime, but in fact, there are winter fireflies like Diaphanes lampyroides that glow and soar over Hong Kong's crisp weather. Unlike most of their relatives, diurnal species such as Pyrocoelia sanguiniventer and Vesta sinuata are most active during the day, before their nocturnal counterparts fill the night with spectacles as dusk settles. While both sexes of adult Abscondita terminalis flash intermittently in the air to attract mates, some females from Lampyrinae give a continuous glow on the ground as they do not bear functional wings nor have the ability to fly.

Of the firefly species recorded, several species are currently considered endemic to Hong Kong but nowhere else, namely Lamprigera taimoshana, Luciola tuberculata and Oculogryphus chenghoiyanae. One must also mention Pteroptyx maipo, a firefly species that was first discovered at the Hong Kong Wetland Park in 2009 and later also found in the Inner Deep Bay area, as well as western Guangdong and Hainan.

View Checklist in Species Database

Dung Beetles

Dung beetles, beetle species that are fond of animal dung, in Hong Kong primarily include representatives from the subfamily Scarabaeinae. Adults prefer feeding on mammalian faeces, typically from herbivores and omnivores, and constructing brood balls and chambers with faeces to house and feed their larvae. By tunnelling and dwelling within the dung, as well as feeding upon and burying it, dung beetles play important roles in accelerating nutrient cycling and enhancing seed dispersal, soil aeration and parasite control in their ecosystems.

Large mammals, especially cattle and buffalo, inhabit a wide range of local habitats including grasslands, shrublands, lowland marshes and agricultural fields, and provide a bountiful supply of faecal feasts to dung beetles in the countryside. To date, Hong Kong has recorded over 50 species of the subfamily Scarabaeinae and is the type locality of 11 among them, including Liatongus pugionatus, Liatongus vertagus, Onthophagus lunatus, Onthophagus convexicollis, Onthophagus luridipennis, Onthophagus proletarius, Onthophagus taurinus, Onthophagus orientalis, Onthophagus trituber, Sisyphus bowringi and Tibiodrepanus sinicus.