Mournful Wasp
Pemphredon lugubris
This record describes Pemphredon lugubris (species). Recorded family: Crabronidae. Recorded order: Hymenoptera.
Identification and Appearance

Length up to 12 mm. There are other very similar species in this family and care is needed with identification. Most solitary bees and wasps are difficult to identify, and can rarely be identified from photos taken in the field. All red-rated records should include a photo or set of photos of the specimen, illustrating the key characters taken from a standard key, which should also be referenced (e.g. ‘Falk, 2015’). The full set of key characters are generally not visible in field photos and photos are rarely sharp enough. To aid in the verification of your records, please include face shot, side, top and wings. The notes should state whether male or female, and explain how the specimen met the key characters. Although NS may not be able to identify the species even if these reference photos are provided, the photos will be stored with the record and may allow it be identified in future. Alternatively, NS will accept records identified by a recognised local or national expert, or that have been identified via BWARS’ Facebook https://www.facebook.com/profile.php?id=100065021433202 . If you have obtained this advice, please note the name of the person/organisation identifying the record in the ‘determiner’ field (e.g. ‘Stuart Roberts, BWARS Facebook’) rather than just a comment of ‘BWARS Facebook’. Often seen in mature woodland and other well wooded areas. Nests in decayed wood feeding the young mainly on aphids. Fairy widespread, particularly in southern Britain.
Classification
- Kingdom
- Animalia
- Phylum
- Arthropoda
- Class
- Insecta
- Order
- Hymenoptera
- Family
- Crabronidae
- Genus
- Pemphredon
Imported taxonomy record. Source availability varies; see the source references and editorial policy below.
Habitat and Range
Habitat
Often seen in mature woodland and other well wooded areas.
Seasonal Activity
Summer and autumn.
Diet and Behavior
Life History
Nests in decayed wood feeding the young mainly on aphids.
Additional species information
Recorded status
Fairy widespread, particularly in southern Britain.
About Flies: the wider group
Order-level background for Hymenoptera, the group containing Pemphredon lugubris. 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 Mournful Wasp (5)
Frequently Asked Questions About Mournful Wasp
What is Mournful Wasp?
Mournful Wasp (Pemphredon lugubris) is a species in the family Crabronidae, within the order Hymenoptera.
How big is Mournful Wasp?
up to 12 mm. There are other very similar species in this family and care is needed with identification.
Where is Mournful Wasp found?
Habitat: Often seen in mature woodland and other well wooded areas.
When is Mournful Wasp active?
Mournful Wasp: seasonal activity - Summer and autumn..
What is the life cycle of a Mournful Wasp?
Nests in decayed wood feeding the young mainly on aphids.
FROM LOOKING IT UP TO GETTING TO KNOW IT
Make sense of the bugs at home.50 household bug profiles for you. Photos, coloring, and activities for curious kids.





