Most people are familiar with the tiny insects that walk on the surface of lakes, ponds, rivers, and even the open sea. A thin layer of fat on the hairs on their abdomen and legs prevents water striders from sinking. Very few people know that these are actually true bugs. Around 800 species are known worldwide, 12 of them are also found in Germany. Zoologists typically sort the animals into species, genera, or subfamilies based on morphological characteristics. To reconstruct the evolutionary relationships within the water strider family, how closely related individual subfamilies or genera are to each other, and when and where they originated in the family tree, other methods are needed—by looking into the DNA.
A new study is now shedding light on the phylogenetic development of the water strider family. The work is the most comprehensive molecular genetic analysis of this insect family to date. A research team led by bug expert PD Dr. Michael Raupach from the Bavarian State Collections of Natural History (SNSB) analyzed the genomes of water strider species from all subfamilies and tribes on a large scale for the first time in order to obtain an overall picture of their family tree. The researchers even succeeded in sequencing DNA from historical collection specimens, the oldest was almost 90 years old. The DNA serves as a molecular clock, recording periods of evolution: the origin of water striders dates back to the Cretaceous period around 100 million years ago, which is around 10 million years later than previously assumed. Just a few million years later, the different subfamilies evolved, leading to the emergence of today's biodiversity. Most lineages originated much earlier than previously known, some up to 50 million years. The diversification was probably driven by various geological and climatic processes that took place on Earth at that time and had a massive impact on the various ecosystems. At that time, the planet was in a phase of extreme greenhouse climate, elevated sea levels, and intense plate tectonic activity.
“Our findings now enable us to better understand the evolution of this fascinating group of insects. They serve as a basis for further research of their biodiversity,” says PD Dr. Michael Raupach, curator of the true bug collection at the SNSB and first author of the study.
Systematic Entomology
Animals
Exploring the phylogenetic history of water striders (Hemiptera: Heteroptera: Gerromorpha) using genome-skimming
21-Jan-2026