Aradidae

Brullé, 1836

Flat Bugs

Subfamily Guides

5

is a of true bugs (Heteroptera) characterized by their dorsoventrally flattened bodies, commonly known as . range from 3 to 11 mm in length and are mostly blackish or brownish. The family exhibits worldwide distribution with greatest diversity in Australia. Most inhabit concealed microhabitats such as under bark of dead trees in temperate regions or in leaf litter and on fallen woody debris in tropical areas.

Aradus intectus by no rights reserved, uploaded by Nick Bédard. Used under a CC0 license.Mezira by (c) Don Loarie, some rights reserved (CC BY), uploaded by Don Loarie. Used under a CC-BY license.Mezira by (c) Guillaume Delaitre, some rights reserved (CC BY), uploaded by Guillaume Delaitre. Used under a CC-BY license.

Pronunciation

How to pronounce Aradidae: /əˈrædɪˌdiː/

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

Identification

Distinguished from other Heteroptera by the combination of: extremely flattened body form; absence of ocelli; four-segmented ; two-segmented ; and long coiled stylets. The rough, debris-covered appearance and association with dead wood or leaf litter further aid recognition. Females frequently wingless or short-winged while males usually fully winged.

Images

Appearance

Body strongly dorsoventrally flattened. Size 3–11 mm. Coloration mostly blackish or brownish. Some have short or reduced wings (brachypterous or in females, in males). often appears rough due to layers of fine debris held by setae. possess long coiled maxillary and mandibular stylets that may reach five times body length when uncoiled. Ocelli absent. with four segments. two-segmented. Metathoracic well developed. Legs sometimes modified for stridulation with scrapers on and files on tibiae; stridulatory combs may occur on fourth ventrite.

Habitat

Temperate commonly occur under bark of dead trees. Tropical species frequently found in leaf litter, on fallen twigs, or on branches. Some species inhabit nests of birds and rodents. Montane species occur in coniferous forests up to subalpine elevations.

Distribution

Worldwide distribution with highest diversity in Australia. Documented from Europe (including first Austrian records), Asia (China, Yunnan), and the Americas. Records from Scandinavia (Denmark, Norway, Sweden) and North America (Vermont, USA).

Diet

Most members are mycophagous, feeding on mycelia of rotting wood. Specific feeding habits remain poorly known for most .

Host Associations

  • Picea abies - associationSpruce forests in montane regions
  • Pinus cembra - associationArolla pine forests

Life Cycle

Most breed twice annually. possess hexagonal reticulation on shells.

Behavior

Often live in groups under bark or in litter. Males remain on top of masses after females deposit eggs. Some attracted to of bark beetles. Capable of stridulation using modified leg structures.

Ecological Role

Decomposer guild associated with fungal decay of dead wood and plant matter.

Human Relevance

Of no economic importance with few exceptions. Occasionally encountered in urban or managed landscapes when associated with dead or dying trees.

Similar Taxa

  • PentatomidaeSome Pentatomoidea share brown coloration and body shape, but distinguished by presence of ocelli, different labial and tarsal segmentation, and lack of extreme dorsoventral flattening
  • CoreidaeLeaf-footed bugs share order-level features but have more cylindrical bodies, different antennal structure, and lack the specialized debris-covering setae of

More Details

Sexual dimorphism in wings

Females frequently brachypterous or ; males typically . This pattern is widespread across the .

Stridulatory apparatus

Leg modifications for sound production include femoral scrapers and tibial files, with combs sometimes present on the fourth ventrite.

Sources and further reading