Julida

Julida is an order of millipedes within the class Diplopoda, comprising many of the cylindrical, commonly encountered millipedes known as juliforms. The name stems from the genus Julus, a typical representative. Members are generally elongated and cylindrical, with a hard exoskeleton and a heavily segmented appearance.

A defining feature of Julida is diplosegmentation: most trunk rings are formed from fused embryonic segments, and each visible segment typically bears two pairs of legs. This results in the characteristic “many-legged” look. Body size and coloration vary widely among species, with individuals ranging from a few centimeters to well over ten centimeters in some cases, and colors from brown or black to patterned yellowish tones.

Distribution and habitat: Julida is widespread, especially in temperate regions of Europe, Asia, and North America, though related forms occur in other areas. They are primarily terrestrial detritivores, living in moist microhabitats such as leaf litter, under logs and rocks, within moss, or in soil.

Ecology and behavior: As decomposers, juliform millipedes contribute to nutrient cycling by breaking down decaying plant matter. Many produce defensive chemicals from repugnatorial glands. They are typically nocturnal or hidden during the day, emerging to feed in moist conditions.

Reproduction: Mating is sexual, with males transferring sperm through specialized structures called gonopods. Females lay eggs in protected, moist sites, and the juveniles hatch and undergo several molts before reaching maturity.