Scarabaeidae

Latreille, 1802

scarabs, scarab beetles

Subfamily Guides

8

is a large of beetles containing over 35,000 worldwide. Members are characterized by —plate-like segments that can be fanned out to detect odors—and often stout, robust bodies. The family exhibits remarkable diversity in size (1.5–160 mm), coloration, and . Many species are , though groups such as flower chafers display bright metallic colors. The family includes dung beetles, rhinoceros beetles, Hercules beetles, Goliath beetles, and numerous agricultural pests. Classification remains unstable, with several former elevated to family rank in recent revisions.

Dialytellus by no rights reserved, uploaded by Nick Bédard. Used under a CC0 license.Calamosternus granarius by (c) Иван Пристрем, some rights reserved (CC BY), uploaded by Иван Пристрем. Used under a CC-BY license.Cryptoscatomaseter magnificens by (c) Colin Croft, some rights reserved (CC BY), uploaded by Colin Croft. Used under a CC-BY license.

Pronunciation

How to pronounce Scarabaeidae: //skærəˈbiːɪdiː//

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

are distinguished by their , in which the terminal segments form leaf-like plates () that can be compressed into a ball or fanned outward. Most have stout, oval to elongated bodies with clubbed antennae that appear knobbed at rest. Many possess forelegs modified for digging, with broad, toothed tibiae. Males of some groups bear prominent horns on the or pronotum. Larvae are C-shaped, pale yellow or white with well-developed legs.

Images

Habitat

occupy diverse including forests, grasslands, agricultural fields, deserts, and wetland edges. Many are , living in soil or burrowing into decaying wood, , or compost. Dung beetles are associated with mammal droppings in pasture and rangeland. Some groups inhabit nests as . Larval stages typically occur underground, in decaying organic matter, or within rotting wood.

Distribution

Worldwide distribution across all continents except Antarctica. Greatest diversity occurs in tropical regions, particularly in the Neotropics, Afrotropics, and Southeast Asia. The is well-represented in temperate North America, Europe, and Australia.

Seasonality

Most scarabs are and active during warmer months. Flower chafers (Cetoniinae) and many leaf (Rutelinae) are and active spring through summer. typically overwinter in soil or decaying matter, with adults emerging in late spring to summer. Specific timing varies by latitude and .

Diet

Highly variable across . Dung beetles (Scarabaeinae) feed on mammal . Many are saprophagous, consuming decaying plant material or carrion. Some, such as the Japanese beetle (Popillia japonica), are herbivorous and feed on living plant foliage, flowers, or roots. Anteater scarabs (Cremastocheilus) are specialized of larvae and pupae. Flower chafers consume nectar, pollen, and sap exuding from tree wounds.

Life Cycle

Complete with , larva, pupa, and stages. Females lay eggs in soil, , compost, decaying wood, or near nests depending on group. Larvae are C-shaped that pass through three instars, feeding and growing for weeks to months. Many overwinter as larvae or . occurs in earthen or within substrate. Adult timing varies; some species live one year, others longer.

Behavior

Many scarabs are strong fliers; flower chafers possess a unique thoracic hinge allowing to remain closed during , producing a -like appearance. Dung beetles exhibit rolling, tunneling, or dwelling with . Some stridulate or produce sounds. Males of horned species engage in combat for mates or resources. Anteater scarabs employ death-feigning to gain entry to nests. Most are , though activity occurs in flower-associated groups.

Ecological Role

Dung beetles provide critical services by recycling nutrients, burying , reducing loads in pastures, and aerating soil. Saprophagous accelerate decomposition of organic matter. Some herbivorous species are significant agricultural pests. The represents an important food source for vertebrate and including birds, mammals, robber flies, and .

Human Relevance

Scarabaeus sacer was sacred in ancient Egypt, with amulets traded throughout the Mediterranean. Several are major agricultural pests: Japanese beetle damages turf and crops; canegrubs attack sugarcane; June beetles and white damage lawns. Dung beetles have been introduced for of and flies in pasture systems. Some species are collected for the pet trade, particularly large horned beetles.

Similar Taxa

  • Passalidae (bess beetles)Flattened, parallel-sided body form and association with decaying wood; distinguished by uniformly segmented and stridulatory sound production when handled.
  • Chrysomelidae (leaf beetles)Similar size and metallic coloration in some ; distinguished by thread-like or clubbed but non- and different leg structure.
  • Elateridae (click beetles)Similar body shape and soil-dwelling larvae; distinguished by straight, serrate or pectinate and the prosternal process that enables the 'click' mechanism.

Sources and further reading