Scoliidae

Scoliid Wasps, Mammoth Wasps

Tribe Guides

3

is a of solitary comprising approximately 300-560 described worldwide. They are robust, often large-bodied wasps with distinctive corrugated wing tips. Females are of scarab beetle larvae, using their stings to paralyze before depositing . The family exhibits pronounced : males have longer and more slender bodies, while females possess shorter antennae and true stingers. Scoliids are considered beneficial insects due to their role in controlling scarab pest .

Dielis plumipes confluenta by (c) aarongunnar, some rights reserved (CC BY), uploaded by aarongunnar. Used under a CC-BY license.Scolia by (c) Louise Woodrich, some rights reserved (CC BY), uploaded by Louise Woodrich. Used under a CC-BY license.Colpa octomaculata by (c) Sam Kieschnick, some rights reserved (CC BY), uploaded by Sam Kieschnick. Used under a CC-BY license.

Pronunciation

How to pronounce Scoliidae: /skɔˈli.aɪdiː/

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

Identification

Scoliids are distinguished from similar Tiphiidae and Thynnidae by less extreme and the distinctive corrugated wing tips. The combination of robust hairy body, spiny legs, and corrugated wing margins separates them from other vespoid wasps. Males can be identified by long and pseudostinger; females by short antennae and true stinger. -level identification often requires examination of punctation patterns, coloration details, and genitalic structures.

Images

Habitat

Terrestrial environments where scarab beetle larvae occur. Females search for in soil, rotting wood, and subterranean larval galleries. frequent flowering plants for nectar. Found in diverse from open woodlands to meadows, gardens, and agricultural areas.

Distribution

Worldwide distribution with approximately 300-560 described . Predominantly tropical and subtropical, with significant representation in North America, South America, Africa, Asia, and Australia. North America has 36 reported species. Nearctic clades show biogeographic patterns consistent with across Beringia during the Oligocene or later Eocene.

Seasonality

active primarily from late summer through fall (July-October in temperate regions), with timing varying by latitude. Some have multiple per year. Males typically emerge before females and patrol territories near sites in morning hours.

Diet

feed on nectar and possibly pollen from diverse flowering plants including goldenrod (Solidago), thoroughworts (Eupatorium), milkweed (Asclepias), white sweet clover (Melilotus alba), and various wildflowers. Larvae are obligate ectoparasitoids of scarab beetle larvae.

Host Associations

Life Cycle

Females locate scarab larvae underground by flying low over soil surface. Upon detection, they dig using spiny legs, sting the larva to paralyze it, and deposit a single transversely on the 's . Some move the paralyzed to a deeper chamber. The larva hatches and feeds as an external for 1-2 weeks, then spins a silken cocoon and overwinters as pre-pupa. occurs the following summer, with emerging to complete the cycle. Some species exhibit or in stages.

Behavior

Females fly low over ground in figure-eight or sinuous patterns searching for larvae. Males patrol territories near sites, especially in morning hours, seeking virgin females. Males may sting multiple hosts without ovipositing, causing permanent paralysis. roost singly or in loose groups on vegetation at night, curling around stems. Some engage in with orchids (e.g., Pygodasis bistrimaculata with Bipinnula penicillata).

Ecological Role

Important biocontrol agents of scarab beetle pests. reduces of economically damaging scarabs including Japanese beetle and other 'white .' contribute to pollination as minor of flowering plants. As specialized , they help regulate scarab in natural and agricultural .

Human Relevance

Beneficial insects for agriculture and horticulture due to scarab pest suppression. Stings are painful but females rarely sting unless physically molested; males cannot sting. Presence of numerous scoliids may indicate significant scarab in lawns or gardens. Some have been introduced for of scarab pests. are conspicuous and often observed by naturalists; some species are among the largest in the world.

Similar Taxa

  • TiphiidaeSimilar lifestyle and associations, but exhibit more extreme with males often wingless or with reduced wings, and lack corrugated wing tips
  • ThynnidaeSimilar and relationships, but show more pronounced and males lack the distinctive corrugated wing margins of
  • Mutillidae (Velvet Ants)Some superficial similarity in robust, hairy appearance, but velvet ants are actually flightless female with different ; males have wings but lack corrugated wing tips and lifestyle

More Details

Taxonomic Complexity

Higher-level of is currently unstable and in need of revision. Recent phylogenomic studies using ultraconserved elements (UCE) data have revealed that several (Campsomeriella, Dielis, Megascolia, Scolia) are non-monophyletic. The Campsomerinae as traditionally constituted is non-monophyletic due to the position of Colpa as sister to Scoliini. Proscolia is confirmed as sister to all other extant scoliids. The originated in the Early Cretaceous with crown diversification in the Late Cretaceous to Paleogene.

Fossil Record

Two are known only from fossils: Archaeoscoliinae (Cretaceous to late Eocene, with highest diversity in Barremian) and Palaeoscoliinae (Late Eocene, single ). These fossil help constrain timing of scoliid diversification but their phylogenetic placement remains uncertain.

Biogeographic Patterns

The Australasian Trisciloa is recovered as sister to remaining Campsomerini sensu stricto. Nearctic scoliid clades show stem ages consistent with across Beringia during the Oligocene or later Eocene, indicating complex historical in the .

Collection and Study Challenges

Despite their large size and conspicuous appearance, many aspects of scoliid remain poorly documented. associations are unknown or inferred for most beyond the general scarab lifestyle. Video documentation of host-finding and oviposition is rare. Females are less frequently collected than males due to their more cryptic, ground-oriented behavior.

Tags

Sources and further reading