European beewolf
European beewolf | |
---|---|
A European beewolf | |
European beewolf paralysing a bee | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Class: | Insecta |
Order: | Hymenoptera |
Family: | Crabronidae |
Genus: | Philanthus |
Species: | P. triangulum
|
Binomial name | |
Philanthus triangulum (Fabricius, 1775)
| |
Synonyms[1] | |
|
The European beewolf (Philanthus triangulum), also known as the bee-killer wasp or the bee-eating philanthus (from the now obsolete synonym Philanthus apivorus), is a solitary
Identification
The European beewolf is a species of solitary wasp with bold yellow and black markings on the abdomen, males have trident-shaped markings between their bluish eyes while the larger females have a reddish stripe behind the eyes and a pale face.[2]
Habitat
The European beewolf is found mainly in areas of open sandy ground in areas such as lowland heathland and coastal dunes.[2] They are infrequently found in clay areas and in Britain have been recorded digging burrows in coal dust and ash and have been found on spoil heaps from coal mining.[3]
Subspecies and distribution
The European beewolf has a wide distribution in the
There are currently five recognised subspecies:[3]
- Philanthus triangulum abdelcader Lepeletier, 1845 northern Africa and the Middle East from Iraq westwards to the Atlantic and the Canary Islands this subspecies also occurs on the Italian island of Lampedusa;
- Philanthus triangulum bimaculatus Magretti, 1908 Kenya;
- Philanthus triangulum diadema (Fabricius 1781) the Afrotopics;
- Philanthus triangulum obliteratus Pic 1917 Algeria and Egypt:
- Philanthus triangulum triangulum (Fabricius, 1775) Europe.
Biology
In the more northerly parts of its distribution the European beewolf is univoltine and the flight period is between mid-July and September. In the warmer area in which it occurs there can be more than one generation per year, for example in Central Europe there may be two broods in the summer.[4]
Female European beewolves excavate their burrows in sandy soil or in vertical soil faces in open sunny places
The humid and warm conditions in the brood cells provide good growth conditions a number of species of mould fungi which can colonise the cells opportunistically from the surrounding soil, especially Aspergillus flavus,[7] which can either infect the larva or the stored immobilised bees and this normally causes the larva to die. Female beewolves protect their offspring against pathogens, and they have evolved strategies to reduce the mortality of their offspring in the brood cell. The first strategy is to apply copious amounts of an anti-condensation secretion from a cephalic gland on to the paralysed bees to reduce water condensation on those bees and thereby delay fungal germination. The second strategy consists of a concentrated release of nitric oxide from the beewolf egg itself once the brood cells is closed by the mother that sterilises the deposited bees by killing actively growing fungi.[8] The third strategy is that the female wasp secretes a whitish substance from specialised glands in its antennae in to the brood cell, this secretion contains symbiotic bacteria of the genus Streptomyces, which are ingested by the larva and before the larva pupates the bacteria are applied to the cocoon to protect the larva from fungal infection.[6]
The males set up territories in vegetation near to the females' nesting aggregations, these territories do not hold any resources to interest the females.[9] The territories are around a quarter of a square metre in extent and are marked with a pheromone from the male's cephalic glands. The males defend these territories from intruding males but the defence does not involve physical contact between the antagonists. Males may have territories which are often close to one another, constituting a form of lek, which allows the females to choose their mates from among the males. The males do not appear to attract the females by using any form of visual display and it is thought that the females choose the males to copulate with based on the quality of the pheromones the male produces.[6] The amount of time the male occupies a territory is dependent on the number of female nests near that territory.[9]
The adult wasps feed on nectar and have been recorded as feeding on nectar from
Nests
Status in the UK
This wasp was previously considered to be one of the great aculeate rarities in Britain, with colonies only in sandy habitats on the Isle of Wight and Suffolk. It has undergone an expansion in range, with the wasp now locally common in a steadily increasing number of sites as far north as Yorkshire (2002). The species has RDB2 status (vulnerable) but, if revised, it is now likely that this status will be removed because of its increase in range and population.[11]
See also
References
- ^ "Synonyms for "Philanthus triangulum"". GBIF.org. Retrieved 20 May 2017.
- ^ a b c d e "Information Sheet The Bee-Wolf (Philanthus triangulum)" (PDF). The Bees Wasps & Ants Recording Society. Retrieved 21 May 2017.
- ^ a b c d J. Smit; R. de Boer (2008). "Philanthus triangulum (Hymenoptera; Crabronidae) new for the fauna of the Canary Islands" (PDF). Linzer Biologische Beiträge. 40 (1): 897–900.
- ^ a b c d e G.R. Else (1997). "Philanthus triangulum (Fabricius,1775)". The Bees Wasps & Ants Recording Society. Retrieved 21 May 2017.
- ^ Trevor Pendleton; Dilys Pendleton. "Bee-killer Wasp Philanthus triangulum (Fabricius, 1775)". Eakring Birds. Retrieved 21 May 2017.
- ^ a b c "Biology of the European beewolf (Philanthus triangulum, Hymenoptera, Crabronidae)". University of Regensburg. Retrieved 21 May 2017.
- .
- PMID 31182189.
- ^ S2CID 25547620.
- S2CID 255488910.
- ^ "Species Account for Philanthus triangulum". Essex Field Club. Archived from the original on 2 June 2008. Retrieved 28 August 2013.