Did you also find a mantis on the balcony?

Mantises are not among the most common insects that can be seen, but they are not exotic animals: in Italy there are at least a dozen different species, native to the Territory. However, if you have recently come across them in a northern city, and in particular on a balcony or terrace, it is likely that they belong to one of the two Asian species that in recent years have begun to spread in the Po Valley.

Tweet embed How did the praying mantis reach the fifth floor of the building? pic.twitter.com/L2P1a8o4rX

– semperfitente (semperfitente) September 6, 2022

Italian mantises are usually not found on trees and do not climb, while the Asian mantis yes, which is why they can also be found on the upper floors of buildings. According to the scientific classification, they all belong to the genus Herodula: The names of the two species are Herodula Tenuidentatawhose common name is the “Asian giant mantis”, and Herodula batelliferaGiant Mantis Indochina.

They are quite similar to each other – to distinguish between the two The front legs should be carefully monitored – but it can be distinguished from the Italian species, and in particular from the more widespread European mantis (Religious Mantis) For two white spots on the wings, in technical terms “stigmas”. Compared to most Italian species, it is larger in size.

According to the studies of entomologist Roberto Battiston, curator of archeology and natural sciences G. Italy at least since 2015 it is now found in almost all of northern Italy, while the Asian giant mantis was first observed in 2016 and spreads across the Po Valley. It began to appear mainly between Cremona, Crema and Mantua, in Lombardy, but in second place Battiston’s latest studyPublished at the end of 2021 in the journal of the Zanato Museum, it is likely that it is expanding in Veneto.

You think That the Asian mantis arrived in Italy from Greece or Ukraine, where it was already widespread, on commercial transport. However, at present, it is unlikely that they come from special groups of insects, although the mantis is of the genus Herodula Among the most requested by enthusiasts. Their arrival from Ukraine may explain their good adaptation to the winter climatic conditions of the Po Valley: according to the observations, Herodula Tenuidentata It remains viable and remains viable even if temperatures remain below 0°C, and as low as -5°C.

The studies by Battiston and colleagues are based largely on reports made not by scientists, but by lay people, through social networks or iNaturalist, the most famous app of participatory science or Citizen science. Reporting can also be done through Exotic Mantis Project website, where it is possible to find different information on both the original Asian and Italian mantis. The project was launched to monitor the spread of exotic species, understand how this occurs and assess its potential impacts on Italian ecosystems: will it harm the Italian mantis? Will it feed on native insects or will it be able to limit the spread of other species from other regions?

At the moment, not many interactions between European and Asian mantis have been observed, and it may be the fact that the latter are often on trees allows for a “peaceful” coexistence.

Nicola Brissi, a zoologist at the Civic Museum of Natural History in Trieste and an expert on the so-called “human dimension of animals,” that is, the social, emotional and economic effects of interactions between people and other species of animals, explained: “If they stay in the city until the end of October, they might help the insects. The autumn. Above all, if they settled in buildings they would not risk exterminating native species.” Preci is careful to stress that the adjective “foreign” does not necessarily mean “negative”: “Invasives are passive. Invasive species are one that enables us to impoverish ecosystems by monopolizing them. Alien species often become invasive (nuts) but not always (tomatoes). And sometimes we make the native (wild boar) invasive.”

There is also a third type of mantis that has appeared in Italy in recent years. It is the African giant mantis (Sphodromantis viridis), which as of 2011 began in Sardinia, where it probably came from Spain, and in 2019 was also found in Sicily. She also has white spots on the wings.