2026 Volume 29 Issue 2 Pages 81-95
Although knowledge of larvae is essential for understanding species, research on larvae of Carabidae (Coleoptera) is limited. While Dolichus halensis is a common species wherein flying individuals also exist, we have little information on the topic. We 1) identified the species of the larvae using DNA barcoding, and clarified their larval stage, 2) investigated the behavior and morphology of the larvae, and interpreted their ecological traits from their morphology. First, to reveal the larval stage, field surveys were conducted and we examined the number of larvae and adults captured. Larvae emerged from October to April, including winter, suggesting that they are active during this period. It was previously known that the larvae overwinter, but we discovered that the third instar larvae overwinter and that their period lasts six months. We examined the morphology and inferred their ecology. Regarding the head, the mandibles were long, curved, and sharp at the tip. Both their morphology and their aggressive behavior suggest that they were carnivorous predators. As for the thorax, the ventral is soft, which is thought to allow the legs to move freely. Regarding the abdomen, the cerci are long, which suggests that they are surface runners. They had a soft, cylindrical tenth abdominal segment, which it used like a suction cup to make stops and change direction. There is little research on larvae of Carabidae, especially on their ecology, therefore we interpreted their ecology in relation to their morphology.
