Pison spinolae, commonly known as mason wasp, is a solitary wasp of the family Crabronidae, found throughout New Zealand.
Description
Like all insects, P. spinolae has a hard exoskeleton, one pair of antennae and three pairs of legs. These legs are strong as they need to be able to carry spiders back to their nests for their young. It has a segmented body divided into three sections; head, thorax and abdomen and two pairs of wings. An easily identifiable feature of the mason wasp, similar to other wasp species is the thin waist between the thorax and abdomen. This helps to tell the difference between a wasp and bee. The mason wasp is able to use its stinger repeatedly unlike bees. It relies on this to inject venom into spiders which paralyses them and allows the adult female to carry the spider back to the nest. Unlike some commonly-known wasps, P. spinolae is not black and yellow, the adult's body is fully black and has a length of approximately . The nest of the mason wasp is constructed from predominantly sand and mud. It is small in size and widely abundant, found in places such as cracks of buildings and keyholes. The most obvious characteristic used for identification is the multiple single compartments sealed off from each other. Each contains a paralysed spider and an offspring of the adult female. Understanding the features of the mason wasp nest make the Juvenile stages easier to identify. The egg of the mason wasp is a white elongated oval shape. Later this develops into larvae which are white with a distinctive head and a translucent cuticle. The larvae then form a cocoon which is cylindrical, grey and rounded at either end.
Distribution
Natural global range
The genus Pison is abundant throughout tropical and temperate regions, mostly in the southern hemisphere. A large number of species are found in Australia. P. spinolae is native to Australia and is thought to have been introduced to New Zealand around 1880.
New Zealand range
The mason wasp is found widely throughout New Zealand. The abundance of this species is relatively common but not of significant abundance to cause drastic effects on its prey populations. It was accidentally introduced from Australia circa the year 1880. Despite being a non-native species, Pison spinolae is by far the most commonly found mason wasp in the country, meaning it has occasionally been called the New Zealand mason wasp.
Habitat preferences
Sand wasps have a diverse range of habitats, from sand dunes to nesting in cracks of buildings. P. spinolae, like other species in the genus Pison, construct nests in holes in wood, keyholes and even crevices on ships and aircraft. This allows humans to widely distribute the species without knowing.
Life cycle/phenology
An egg is laid by the female adult which is a white elongated oval shape. This develops into larvae which are white with a distinctive head and a translucent cuticle. In less than three weeks the final larval stage is reached. The formation of the cocoon begins within one month after the egg was laid. The cocoon of the Pison genus are cylindrical, grey and rounded at either end. Unlike most New Zealand sphecids P. spinolae is bivoltine. This includes a summer generation without a diapause and a winter generation with diapause. All New Zealand species in the family Sphecidae spend at least the winter in a prepupal diapause. In the spring following the diapause the prepupa moults into an exarate pupa which is a pupal stage with moveable appendages. Pupal development occurs for 14 days and results in an adult wasp emerging. At the time of emergence solitary male wasps patrol nesting areas. This is when the females’ reproductive cycle is most sexually receptive. Most solitary wasp species will mate just once in their lives, this is generally at the time of emergence. Mating attempts have not been observed around feeding sites or other locations. It is not known if this mating behaviour is different in bivoltine species such as P. spinolae, where males of the first generation could possibly mate with females of both generations if they live long enough.
