jumperids

Jumperids is a common informal term used to refer to the jumping spiders, members of the family Salticidae within the order Araneae. The label is not a formal taxonomic rank, but it is widely used in field guides, amateur natural history, and some regional vernaculars. Salticidae comprises the most species-rich and visually oriented group of spiders, with over 6,000 described species found worldwide.

Morphology and vision: Jumping spiders share a compact body, short spinnerets, and the hallmark feature of four pairs of eyes, with the anterior median eyes notably large and forward-facing, giving acute color and motion vision. This suite of eyes enables precise depth perception and complex visual signaling. Color patterns range from cryptic browns to iridescent scales in some species. Adults vary in size from a few millimeters to over a centimeter.

Behavior and ecology: Jumping spiders are diurnal hunters that rely on stalking and ambush rather than webs. They actively stalk prey and use rapid leaps to close distances, guided by their vision. They build silk retreats for safety and egg sacs but do not rely on prey capture via capture webs. Mating involves distinctive courtship behaviors, including leg tapping and body vibrations by males; females lay eggs in silken sacs, often guarded by the female.

Distribution and relevance: They occur on every continent except Antarctica, in habitats from forests to grasslands and human structures. They are generally considered harmless to humans. Taxonomically, their distinctive eye arrangement and hunting strategy have made them a model group for studies of vision, cognition, and behavior.