Subtribe Tacuina

Tacuina is a subtribe of true cicadas within the tribe Tacuini (Subfamily Cicadinae, Family Cicadidae, Superfamily Cicadoidea, Infraorder Cicadomorpha, Order Hemiptera). Members of this subtribe are distributed primarily throughout South and Southeast Asia, where they inhabit tropical and subtropical rainforests, deciduous forests, forest margins, plantations, and wooded landscapes. They are closely associated with mature trees, which provide both feeding sites for adults and host roots for their subterranean nymphs.

Cicadas of the subtribe Tacuina are generally medium to very large insects with a robust body, broad head, and two pairs of transparent membranous wings marked by conspicuous venation. Their coloration commonly includes shades of green, brown, black, and olive, often accented with yellow, orange, or reddish markings that provide camouflage among tree bark and foliage. They possess large compound eyes, three ocelli, short bristle-like antennae, and piercing-sucking mouthparts adapted for feeding on plant sap.

Adults are predominantly diurnal, although some species may be most active during dawn or dusk. Males produce loud, species-specific calling songs using paired tymbals, specialized sound-producing organs located on the first abdominal segment. These calls are used to attract females, establish territories, and maintain species recognition, and they contribute significantly to the characteristic soundscape of tropical forests.

Both adults and nymphs feed exclusively on xylem sap. Adults obtain sap from the branches and trunks of trees, while the nymphs spend several years underground feeding on the roots of woody plants. Because xylem sap is low in nutrients, these insects consume large quantities of fluid and excrete excess water.

The life cycle follows incomplete metamorphosis, consisting of egg, nymph, and adult stages. Females deposit eggs into slits cut in twigs or branches. After hatching, the nymphs drop to the ground and burrow into the soil, where they develop through several molts while feeding on root sap. Mature nymphs emerge from the soil, climb nearby vegetation or tree trunks, and molt into winged adults, leaving behind the characteristic exuviae attached to vertical surfaces.

The subtribe includes impressive genera such as Tacua and Megapomponia, whose species are among the largest cicadas in the world and are noted for their powerful flight and exceptionally loud calls.

Ecologically, Tacuina cicadas are important herbivores that transfer energy from woody plants to higher trophic levels. Their underground nymphs contribute to soil aeration and nutrient cycling, while adults provide a rich seasonal food source for birds, mammals, reptiles, amphibians, spiders, and predatory insects. Their reliance on mature forests and long developmental cycles makes them valuable indicators of forest health, habitat continuity, and biodiversity.