European beewolf

Last updated

European beewolf
Wasp August 2007-12.jpg
A European beewolf
Wasp and bee August 2008-2.jpg
European beewolf paralysing a bee
Scientific classification OOjs UI icon edit-ltr.svg
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]
  • Philanthus abdelcader Lepeletier, 1845
  • Philanthus allionii Dahlbom, 1845
  • Philanthus apivorus Latreille, 1799
  • Philanthus discolorPanzer, 1799
  • Philanthus pictus Panzer, 1797
  • Crabro androgynusRossi, 1792
  • Philanthus ruspatrix(Linnaeus, 1767)
  • Simblephilus triangulum(Fabricius, 1775)
  • Sphex scutellatus subsp. maculatus Christ, 1791
  • Vespa fasciata Fourcroy, 1785
  • Vespa limbata Olivier, 1792
  • Vespa ruspatrix Linné, 1767
  • Vespa triangulum Fabricius, 1775

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 wasp that lives in the Western Palearctic and Afrotropics. Although the adults of the species are herbivores (feeding on nectar and pollen), the species derives its name from the behaviour of the inseminated females, who hunt Western honey bees. The female places several of its paralysed prey together with an egg in a small underground chamber, to serve as food for the wasp larvae. All members of the genus Philanthus hunt various species of bees, but P. triangulum is apparently the only one that specialises in Western honey bees.

Contents

Identification

Male beewolf visiting a Eryngium flower. Philanthus triangulum-(dkrb).jpg
Male beewolf visiting a Eryngium flower.
beewolf with honey bee Beewolf with honey bee.jpg
beewolf with honey bee

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 Afrotropical and Western Palearctic zoogeographical regions from Scandinavia to South Africa. [3] In Europe its distribution has been moving northwards as summers have longer periods of warm weather. [2]

There are currently five recognised subspecies: [3]

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 [2] and these can be up to a metre in length with no less than three and as many as 34 short side tunnels at the end, each of which contains a brood cell. The material displaced by the burrowing wasp is flicked behind it as it excavates the nest. [5] They nest in aggregations which may have as many as 15,000 burrows. [4] The females hunt honey bees Apis mellifera , which are paralysed with the stinger, the female stinging the prey through the articular membranes which are situated behind the front legs, the female then carries the immobilised bee to the nest in flight between the wasp's legs. On reaching the nest she often hovers over the entrance before slowly descending into the burrow. [4] Each brood cell is provisioned with between one and five honey bees for the larva. After the larva has fed sufficiently it spins a cocoon, the cocoon is attached to the wall of the brood cell at its base. In cooler regions the larva overwinters and the adults emerge the following summer. [6] Other species of bee, other than honey bees, have been reported as prey including Andrena flavipes , Lasioglossum zonulus and Nomada sp in Britain [4] as well as bees of the genera Dasypoda , Halictus and Megachile in continental Europe. [3] Each female may collect up to 100 bees during its flight period. [2]

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 bramble, sea-holly, Erica , thrift, pale toadflax Linaria repens , common ragwort, hemp-agrimony and creeping thistle. [4]

Nests

Niko Tinbergen made a series of carefully designed experiments demonstrating Philanthus identifies its nest by sight. [10]

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

Related Research Articles

<span class="mw-page-title-main">Bee</span> Clade of insects

Bees are winged insects closely related to wasps and ants, known for their roles in pollination and, in the case of the best-known bee species, the western honey bee, for producing honey. Bees are a monophyletic lineage within the superfamily Apoidea. They are currently considered a clade, called Anthophila. There are over 20,000 known species of bees in seven recognized biological families. Some species – including honey bees, bumblebees, and stingless bees – live socially in colonies while most species (>90%) – including mason bees, carpenter bees, leafcutter bees, and sweat bees – are solitary.

<i>Megachile rotundata</i> Species of bee

Megachile rotundata, the alfalfa leafcutting bee, is a European bee that has been introduced to various regions around the world. As a solitary bee species, it does not build colonies or store honey, but is a very efficient pollinator of alfalfa, carrots, other vegetables, and some fruits. Because of this, farmers often use M. rotundata as a pollination aid by distributing M. rotundata prepupae around their crops. Each female constructs and provisions her own nest, which is built in old trees or log tunnels. Being a leafcutter bee, these nests are lined with cut leaves. These bees feed on pollen and nectar and display sexual dimorphism. This species has been known to bite and sting, but it poses no overall danger unless it is threatened or harmed, and its sting has been described as half as painful as a honey bee's.

<span class="mw-page-title-main">Megachilidae</span> Cosmopolitan family of bees

Megachilidae is a cosmopolitan family of mostly solitary bees. Characteristic traits of this family are the restriction of their pollen-carrying structure to the ventral surface of the abdomen, and their typically elongated labrum. Megachilid genera are most commonly known as mason bees and leafcutter bees, reflecting the materials from which they build their nest cells ; a few collect plant or animal hairs and fibers, and are called carder bees, while others use plant resins in nest construction and are correspondingly called resin bees. All species feed on nectar and pollen, but a few are kleptoparasites, feeding on pollen collected by other megachilid bees. Parasitic species do not possess scopae. The motion of Megachilidae in the reproductive structures of flowers is energetic and swimming-like; this agitation releases large amounts of pollen.

<i>Sphecius speciosus</i> Species of wasp

Sphecius speciosus, often simply referred to as the cicada killer or the cicada hawk, is a large, solitary digger wasp species in the family Crabronidae. The name may be applied to any species of crabronid that preys on cicadas, though in North America, it is typically applied to this species, also referred to as the eastern cicada killer in order to further differentiate it from the multiple other examples of related wasp species. Sometimes, they are called sand hornets, although they are not hornets, which belong to the family Vespidae. This species can be found in the Eastern and Midwest U.S. and southwards into Mexico and Central America. They are so named because they hunt cicadas and provision their nests with them. Cicada killers exert a measure of natural control on cicada populations, and as such, they may directly benefit the deciduous trees upon which the cicadas feed.

<i>Osmia lignaria</i> Species of bee

Osmia lignaria, commonly known as the orchard mason bee or blue orchard bee, is a megachilid bee that makes nests in natural holes and reeds, creating individual cells for its brood that are separated by mud dividers. Unlike carpenter bees, it cannot drill holes in wood. O. lignaria is a common species used for early spring fruit bloom in the United States and Canada, though a number of other Osmia species are cultured for use in pollination.

<span class="mw-page-title-main">Beewolf</span> Genus of wasps

Beewolves, also known as bee-hunters or bee-killer wasps, are solitary, predatory wasps, most of which prey on bees, hence their common name. The adult females dig tunnels in the ground for nesting, while the territorial males mark twigs and other objects with pheromones to claim the territory from competing males.

<i>Philanthus gibbosus</i> Species of wasp

Philanthus gibbosus, the hump-backed beewolf, is a species of bee-hunting wasp and is the most common and widespread member of the genus in North America. P. gibbosus is of the order Hymenoptera and the genus Philanthus. It is native to the Midwestern United States and the western Appalachians. P. gibbosus are often observed to visit flowers and other plants in search of insect prey to feed their young. The prey that P. gibbosus catches is then coated in a layer of pollen and fed to the young wasps.

Philanthotoxins are components of the venom of the Egyptian solitary wasp Philanthus triangulum, commonly known as the European beewolf. Philanthotoxins are polyamine toxins, a group of toxins isolated from the venom of wasps and spiders which immediately but reversibly paralyze their prey. δ-philanthotoxin, also known as PhTX-433, is the most active philanthotoxin that can be refined from the venom. PhTX-433 functions by non-selectively blocking excitatory neurotransmitter ion channels, including nicotinic acetylcholine receptors (nAChRs) and ionotropic glutamate receptors (iGluRs). Synthetic analogues, including PhTX-343 and PhTX-12, have been developed to improve selectivity. While the IC50 values of philanthotoxins varies between analogues and receptor subunit composition, the IC50 value of PhTX-433 at the iGluR AMPA receptor naturally expressed in locust leg muscle is 18 μM and the IC50 value at rat nAChRs is 1 μM.

<i>Osmia bicornis</i> Species of bee

Osmia bicornis is a species of mason bee, and is known as the red mason bee due to its covering of dense gingery hair. It is a solitary bee that nests in holes or stems and is polylectic, meaning it forages pollen from various different flowering plants. These bees can be seen aggregating together and nests in preexisting hollows, choosing not to excavate their own. These bees are not aggressive; they will only sting if handled very roughly and are safe to be closely observed by children. Females only mate once, usually with closely related males. Further, females can determine the sex ratio of their offspring based on their body size, where larger females will invest more in diploid females eggs than small bees. These bees also have trichromatic colour vision and are important pollinators in agriculture.

<span class="mw-page-title-main">Wasp</span> Group of insects

A wasp is any insect of the narrow-waisted suborder Apocrita of the order Hymenoptera which is neither a bee nor an ant; this excludes the broad-waisted sawflies (Symphyta), which look somewhat like wasps, but are in a separate suborder. The wasps do not constitute a clade, a complete natural group with a single ancestor, as bees and ants are deeply nested within the wasps, having evolved from wasp ancestors. Wasps that are members of the clade Aculeata can sting their prey.

<i>Philanthus pulchellus</i> Species of wasp

Philanthus pulchellus is a species of bee-hunting wasp of the Iberian Peninsula. Males are territorial and establish territories in nesting areas of females, or in the case of smaller males that are unable to do so, nearby. Females are generalist predators of bees and wasps, including conspecifics, and store the prey in their underground nest.

<i>Hedychrum rutilans</i> Species of wasp

Hedychrum rutilans is a species of cuckoo wasps. The species occurs primarily in Austria, Italy, Bulgaria, Greece, France, Poland, Portugal, Spain, Switzerland and in North Africa. The head and thorax are metallic green with red spots, while the abdomen is red. The color is more green and partially golden in the male and more extensively golden-red in the female. The body is somewhat hairy.

<i>Bombus fervidus</i> Species of bee

Bombus fervidus, the golden northern bumble bee or yellow bumblebee, is a species of bumblebee native to North America. It has a yellow-colored abdomen and thorax. Its range includes the North American continent, excluding much of the southern United States, Alaska, and the northern parts of Canada. It is common in cities and farmland, with populations concentrated in the Northeastern part of the United States. It is similar in color and range to its sibling species, Bombus californicus, though sometimes also confused with the American bumblebee or black and gold bumblebee. It has complex behavioral traits, which includes a coordinated nest defense to ward off predators. B. fervidus is an important pollinator, so recent population decline is a particular concern.

<i>Sphecius grandis</i> Species of wasp

Sphecius grandis, also called the western cicada killer, is a species of cicada killer wasp (Sphecius). The western species shares the same nesting biology as its fellow species, the eastern cicada killer. S. grandis, like all other species of the genus Sphecius, mainly provides cicadas for its offspring. It forms nest aggregations and mates and broods once in a year, in July and early August. The wasp is on average 3 cm (1 in) to 5 cm (2 in) in length and is amber-yellow with yellow rings on its abdomen.

<i>Ammophila sabulosa</i> Species of wasp

Ammophila sabulosa, the red-banded sand wasp, is a species of the subfamily Ammophilinae of the solitary hunting wasp family Sphecidae, also called digger wasps. Found across Eurasia, the parasitoid wasp is notable for the mass provisioning behaviour of the females, hunting caterpillars mainly on sunny days, paralysing them with a sting, and burying them in a burrow with a single egg. The species is also remarkable for the extent to which females parasitise their own species, either stealing prey from nests of other females to provision their own nests, or in brood parasitism, removing the other female's egg and laying one of her own instead.

<i>Anoplius viaticus</i> Species of wasp

Anoplius viaticus, commonly known as the black-banded spider wasp, is a species of spider wasp. These wasps are known as spider wasps because the females capture spiders to provide their offspring with food. The paralysed spider is cached in a burrow, the wasp lays an egg on it, and when this hatches, the developing wasp larva consumes the spider. This species is found in sandy heathland across most of Europe.

<i>Crabro cribrarius</i> Species of wasp

Crabro cribrarius, common name slender bodied digger wasp, is a species of wasp of the family Crabronidae.

<i>Pison spinolae</i> Species of insect

Pison spinolae, commonly known as mason wasp, is a solitary wasp of the family Crabronidae, found throughout New Zealand.

<i>Cerceris rybyensis</i> Species of wasp

Cerceris rybyensis, the ornate tailed digger wasp, is a Palearctic species of solitary wasp from the family Crabronidae which specialised in hunting small to medium-sized mining bees. It is the type species of the genus Cerceris and was named as Sphex rybyensis by Carl Linnaeus in 1771.

<i>Centris analis</i> Species of bee

Centris analis is a solitary, oil-collecting bee with a geographical range extending from Brazil to Mexico. C. analis is a small, fast-flying bee with an average head width of 3.21mm and 3.54mm for males and females, respectively. While most species of the genus Centris create burrows for nesting, C. analis and other species of the subgenus Heterocentris build nests in pre-existing cavities rather than in the ground. C. analis is a pollinator of many plant species, especially of those in the family Malpighiaceae, which has encouraged its application in acerola orchards.

References

  1. "Synonyms for "Philanthus triangulum"". GBIF.org. Retrieved 20 May 2017.
  2. 1 2 3 4 5 "Information Sheet The Bee-Wolf (Philanthus triangulum)" (PDF). The Bees Wasps & Ants Recording Society. Retrieved 21 May 2017.
  3. 1 2 3 4 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.
  4. 1 2 3 4 5 G.R. Else (1997). "Philanthus triangulum (Fabricius,1775)". The Bees Wasps & Ants Recording Society. Retrieved 21 May 2017.
  5. Trevor Pendleton; Dilys Pendleton. "Bee-killer Wasp Philanthus triangulum (Fabricius, 1775)". Eakring Birds. Retrieved 21 May 2017.
  6. 1 2 3 "Biology of the European beewolf (Philanthus triangulum, Hymenoptera, Crabronidae)". University of Regensburg. Retrieved 21 May 2017.
  7. Tobias Engl; Bettina Bodenstein; Erhard Strohm (2016). "Mycobiota in the brood cells of the European beewolf, Philanthus triangulum (Hymenoptera: Crabronidae)". European Journal of Entomology. 113: 271–277. doi: 10.14411/eje.2016.033 . hdl: 21.11116/0000-0007-E720-0 .
  8. Strohm E; Herzner; Ruther J; Kaltenpoth M & Engl T (June 2019). "Nitric oxide radicals are emitted by wasp eggs to kill mold fungi". eLife. 8. doi: 10.7554/eLife.43718 . PMC   6559793 . PMID   31182189.
  9. 1 2 Johannes Kroiss; Klaus Lechner; Erhard Strohm (2009). "Male territoriality and mating system in the European beewolf Philanthus triangulum F. (Hymenoptera: Crabronidae): evidence for a "hotspot" lek polygyny". Journal of Ethology. 28 (2): 295–304. doi:10.1007/s10164-009-0185-5. S2CID   25547620.
  10. Gadagkar, Raghavendra (August 2018). "How to Design Experiments in Animal Behaviour: 1. How Wasps Find Their Nests" (PDF). Resonance. 23 (8): 871–884. doi:10.1007/s12045-018-0690-3. S2CID   255488910.
  11. "Species Account for Philanthus triangulum". Essex Field Club. Archived from the original on 2 June 2008. Retrieved 28 August 2013.