[8] In current literature, P. alternata has been classified as potentially synonymous with another species, Parischnogaster timida discovered by Williams in 1928.

These two species are both a part of the striatula-group due to shared descriptive characteristics such as the length and width of the petiole and the separation of the clypeus from the eye.

[3] The black hover wasps inhabit the tropical rain forests of two Southeast Asian countries: Malaysia (Sarawak and Sabah) and Singapore.

[2] Parischnogaster alternata builds dense clusters of nests in dark, damp cavities including caves and man-made structures such as vaults under bridges, water pipes, and the ceilings of grottoes.

The time of brood development is currently unknown but likely averages between 44 and 53 days based on close relatives P. nigricans and P. mellyi respectively.

[4] Some nests contain 2 or more overlapping subgroups (eggs laid around the same time), indicating that the average reproductive span of the dominant female may be short.

Female helpers indirectly obtain benefits in fitness because the reproductive duration of the foundress is relatively short.

This anatomical feature of helpers may be indicative of a selective trait for preparedness for when the current dominant female stops reproducing.

A few known reasons for visitations can include becoming a new, often non-related helper, sharing of food, stealing eggs or abdominal substance, and feeding on drops of fluid on patches.

The final stage consists of collecting another patch of abdominal substance to place on top of the egg in the cell.

Since P. alternata typically take on flight as an active defense, this method helps the female save the egg they are laying if disturbed by an attack.

Due to the high risk of predation and environmental pressures, female offspring may have a better chance at reproduction by staying to help as opposed to independently founding their own site.

Similar to other eusocial species with dominance hierarchies, P. alternata have female-biased sex ratios of up to 71% females in a colony.

The female-biased sex ratio may be indicative of the fact that male offspring do not stay on their natal nests as long as females.

Through cooperative defense, some residents drive away the hornets while the wasps fall from the nest in order to save the adult individuals.

These materials contribute to the pale brown color of the nests allowing them to blend in with surrounding trees and plants.

[11] Seemingly working against efforts of mimicry, P. alternata often construct nests in clusters, which potentially attract attention due to size.

Two majors reasons for clustering include reduced predation due to the dilution effect and improved hunting.

[3] The dilution effect assumes that by aggregating in a larger group, the chances of predator attack are significantly reduced.

In addition, the theory proposes that individuals will seek center positions in the group to further reduce their chances of attack.

It is assumed that the advantages of passive protection from predation served as a major evolutionary factor that resulted in nest clusters in P.