麻豆淫院

Researchers at Meijo University and University of Tsukuba collected and taxonomically re-examined numerous enigmatic jumping bristletails. These were first reported 75 years ago. The team observed extreme specialization in the external genitalia of the males and discovered that this species belongs to a unique group, potentially representing a primitive state leading to "copulation" during evolutionary development. The study is in Zootaxa.

Insects account for 75% of all animal species, making them the most diverse animal group. Of these, 99% belong to Pterygota, which have acquired wings, while the remaining 1% consist of primitive groups collectively known as Apterygota. Apterygota, which have not yet evolved wings, include Protura, Collembola, Diplura, Archaeognatha, and Zygentoma.

Jumping bristletails are a subgroup of Apterygota that are approximately 15 mm long. They feed on green algae that grow on land and inhabit damp, shaded environments such as moistened rock faces and tree bark. It is hypothesized that the ancestors of terrestrial insects initially fed on algae that advanced onto land simultaneously. Jumping bristletails retained many primitive traits, such as their morphological characteristics, providing significant insights into early insect evolution.

Approximately 75 years ago, Halomachilis kojimai (Japanese name: kojima-ishinomi) was described in Akkeshi, Hokkaido. However, the description was preliminary and inadequate and the original samples were lost. In this study, researchers collected numerous specimens of jumping bristletails identified as the same species and clarified their taxonomy.

The findings revealed that this species belongs to the genus Petrobiellus Silvestri, which is endemic to the Far East and includes only a few known species. A detailed examination confirmed that this species exhibits unique characteristics, contributing to the understanding of innovations in mating behavior essential for the evolutionary transition of insects to terrestrial life.