Macrotomini

Distinguished from other Prioninae tribes by combination of: large body size with robust build; mandibular structure (prominent, often sexually dimorphic); relatively short antennae compared to body length; and specific antennal morphology (serrate or weakly pectinate in many genera). Differs from closely related tribes such as Prionini by mandible shape and antennal proportions. Genus-level identification requires examination of mandible dentition, antennal segment ratios, and pronotal structure.

Large-bodied beetles, typically 20–60 mm in length. Robust, somewhat flattened or cylindrical body form. Prominent, often enlarged mandibles, especially in males. Antennae usually shorter than body length, sometimes serrate or pectinate. Elytra may be smooth, punctate, or ridged. Coloration commonly black, brown, or reddish-brown, sometimes with contrasting patterns.

Associated with forested and woodland environments. Larval development occurs in dead or dying wood of hardwood trees and shrubs. Adults often found on or near host trees, particularly where bark is damaged or wood is decaying. Some species inhabit savanna or open woodland with scattered trees.

Widespread in tropical and subtropical regions. Present in the Afrotropical, Oriental, Australasian, and Neotropical realms. Absent or poorly represented in temperate regions of the Northern Hemisphere. Greatest species diversity in Africa, Southeast Asia, and South America.

Adult activity generally coincides with warm seasons in respective regions. In tropical areas, activity may occur year-round with peaks during rainy seasons. Temperate zone species active primarily in late spring through summer. Many species are attracted to lights at night.

Larvae feed on dead or decaying wood of angiosperm trees, acting as primary decomposers. Some species have been recorded from coniferous wood. Adults may feed on sap, bark, or not at all; specific adult feeding habits are poorly documented for most species.

• Angiosperm trees (various) - larval hostDead or dying wood of hardwood species

Complete metamorphosis with prolonged larval stage. Eggs laid in cracks or under bark of host wood. Larvae tunnel through wood, creating galleries; development may take 1–3 years depending on species and conditions. Pupation occurs in wood chambers. Adults emerge through exit holes.

Adults are primarily nocturnal and attracted to artificial light sources. Males use enlarged mandibles in combat with rival males. Both sexes may stridulate by rubbing body parts together, producing audible sounds. Flight capability varies; some species are strong fliers while others are relatively sedentary.

Contribute to wood decomposition and nutrient cycling in forest ecosystems. Larval tunneling creates habitat for other invertebrates and facilitates fungal colonization of dead wood. Serve as prey for birds, mammals, and other insects.

Some larger species are collected for the insect trade due to their impressive size and mandibles. Occasional pests of timber, though rarely causing significant economic damage. Presence in dead wood can indicate forest health and decay processes.

• PrioniniAlso large Prioninae with prominent mandibles, but differ in antennal proportions (often longer relative to body) and mandibular structure
• MallodoniniOverlapping distribution and morphology; distinguished by details of mandible dentition and pronotal shape

• Cerambycidae
• Prioninae
• longhorn beetles
• wood-boring beetles
• tropical beetles
• saproxylic insects

• BugGuide
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life