Platygaster
This record describes Platygaster (genus). Recorded family: Platygastridae. Recorded order: Hymenoptera.
Identification and Appearance
A huge, hyper-diverse genus containing nearly 700 described species (over 70 species recorded from Britain), making it one of the classic dark taxa of the insect world. Small solitary wasps 1-3mm in length. Glossy black or dark metallic brown. Antennae geniculate (elbowed) and typically composed of 10 segments in both males and females, inserted very low on the face, right down next to the mouthparts. Wing venation very reduced, essentially veinless. The first and second abdominal tergites (dorsal plates) are distinct and not fused, distinguishing Platygaster from its close relative Synopeas , where T1 and T2 are fused into a single rigid structure. The large second tergite (T2) often features distinct, fine longitudinal grooves or striae radiating from its base. Unless identified by a recognised expert, photos of key features are required. Koinobiont endoparasitoids of gall-midges (Cecidomyiidae).
Classification
- Kingdom
- Animalia
- Phylum
- Arthropoda
- Class
- Insecta
- Order
- Hymenoptera (Ants, Bees, Wasps and Sawflies)
- Superfamily
- Platygastroidea
- Family
- Platygastridae
- Subfamily
- Platygastrinae
- Genus
- Platygaster
Imported taxonomy record. Source availability varies; see the source references and editorial policy below.
Habitat and Range
Seasonal Activity
All year.
Diet and Behavior
Life History
Koinobiont endoparasitoids of gall-midges (Cecidomyiidae).
Additional species information
Recorded status
Widespread.
About Flies: the wider group
Order-level background for Hymenoptera, the group containing Platygaster. Species-specific details appear above.
Group overview
Hymenoptera includes over 150,000 described species of ants, bees, wasps, and sawflies. Earth harbors approximately 20 quadrillion (20×10^15) ants, with a combined biomass of ~12 megatons of dry carbon - exceeding the combined biomass of all wild birds and mammals (PNAS, 2022).
Ecological role of the group
About 35% of the world's food crops depend on animal pollinators. The chocolate industry, valued at over $100 billion, depends on pollinating flies and midges. Ants are the dominant soil engineers in most terrestrial ecosystems, turning more soil than earthworms in many habitats.
Economic and practical significance of the group
Pollinators contribute $235-577 billion worth of annual global food production (FAO). In the U.S., bee pollination alone benefits crops valued at $18 billion annually, and honey bees are responsible for $5.4 billion in agricultural productivity. Between April 2023-2024, 55.1% of managed honey bee colonies were lost. The U.S. bee population dropped from 5 million to 2.5 million.
Recorded sources for this group: FAO, USDA, EPA, PNAS (2022), US Fish & Wildlife Service. Imported estimates may describe particular regions or reporting periods.
Photos of Platygaster (7)
Frequently Asked Questions About Platygaster
What is Platygaster?
Platygaster is a genus in the family Platygastridae, within the order Hymenoptera.
When is Platygaster active?
Platygaster: seasonal activity - All year..
What is the life cycle of a Platygaster?
Koinobiont endoparasitoids of gall-midges (Cecidomyiidae).