[3] P. snelleni is typically found in hilly or submontane areas, so they are classified in the semi-highland category.

[2] The weight of new reproductive females (young queens) is 102 mg. Workers can be identified by white-creamy body fat.

[3] The founding queen uses twigs or the surface of rock overhangs as horizontal supports for the nest.

[5] Their nests are typically found on south-facing slopes in areas filled with small trees and short weeds.

The temperature in these sites rises in the daytime because the rocks absorb heat from the sun.

[2] In northern Japan near Sapporo, nests are covered with snow until early April.

About 2 weeks later, the single founding queen arrives to start the nest, falling under the category of haplometrotic foundation.

These emerge in late August when only a few workers remain in the nest and the food supplies have dwindled.

[2] The rate of construction of the nest begins as relatively high and then drops with the hatching of larvae.

[7] Later, the rate of construction picks up again, in conjunction with the maturation of larvae and cocoon spinning by the founding queen.

The superindividual stage, where workers and the queen coexist harmoniously to meet the needs of the nest, lasts only about a week.

This may not occur right at sunrise, but in the later months when the temperature is higher, the queen can start her activities earlier.

Males rest in the nest and beg the workers for food, occasionally visiting flowers.

Females rarely leave the brood, only sometimes to bring water drops to ventilate the nest on hot days.

[2] P. snelleni exists in temperate locations, where cold and hot weather conditions can arise.

Water drops are carried by the wasps and put on the concave nest roof.

The queen sucks fluid from a pellet on the nest or nearby, and feeds it to the young larvae.

When P. snelleni notice that E. japonicus is near the nest, they flutter their wings and dart on the comb.

It is beneficial for P. snelleni to kill the parasitoid larvae because adult E. japonicus could reparasitize the nest.

[7] Orphaned workers have the ability to mate and produce female offspring, but they only begin to oviposit after the queen has disappeared.

It has been said that P. snelleni goes by the mode of serial polygyny, however this was disproven because by the time new reproductive females are ready to reproduce, the season is ending.

[7] Since the founding queens of P. snelleni are likely to disappear, it is necessary that these orphaned workers have the ability to reproduce females for future generations to exist.

This is driven by sexual selection for the optimum sex ratio, and so there is a higher fitness for all.

Because of protandrous production, orphaned workers are selected to produce female offspring, since they are reproducing so late in the season.