Four-spot orb-weaver
Araneus quadratus
The four-spot orb-weaver is one of the heaviest native spider species in Europe and belongs to the family Araneidae. Its abdomen is almost spherical and features four distinctive white spots arranged in a trapezoid, giving the species its name. The base coloration is highly variable, ranging from light green and yellow to orange and dark reddish-brown. It prefers damp meadows and tall herb communities, where it constructs large orb webs at low heights between grasses and perennials.
Details
Identification
Four white spots on the abdomen, highly variable base color (green, yellow, red, brown), robust and almost spherical abdomen in females, significantly smaller males, hairy legs with dark rings.
Social behavior
Solitary and territorial; the spider occupies its own web and does not tolerate conspecifics in the immediate vicinity.
Diet
Insectivorous; primarily feeds on flying insects such as flies, bees, wasps, and grasshoppers caught in the web.
Hunting strategy
Construction of a vertical orb web with a signal thread leading to a usually bell-shaped retreat made of spun-together leaves.
Overwintering
The species overwinters in the egg stage within a protective cocoon; adult individuals die in late autumn.
Ecology
Ecological role
Important predator in meadow ecosystems for the control of insect populations.
Natural predators
Birds, ichneumon wasps (as larval parasitoids), lizards, and larger predatory spiders.
Competitor species
Other large orb-weaving spiders such as the European garden spider (Araneus diadematus) or the wasp spider (Argiope bruennichi).
Ecosystem service
Natural pest control by consuming large quantities of insects.
Threats
Agricultural intensification, frequent mowing of meadows, drainage of wetlands, and the use of insecticides.
Scientific profile
Profile
Distinguishing features
In addition to the four eponymous spots, the species is characterized by a very voluminous, almost spherical abdomen in females. A key feature is the construction of a bell-shaped, downward-opening retreat made of silk and plant matter, positioned laterally above the web.
Habitat
Prefers open, moist to wet habitats such as wet meadows, bogs, sedge marshes, and fallow land with a tall, stable herb layer. Occasionally found at forest edges or in gardens.
Role in food web
Significant regulator of insect populations in wetlands; serves as an important food source for insectivorous birds and specialized wasps.
Protection & threats
Main threats
Loss of wetlands due to drainage, intensification of agriculture (frequent mowing), scrub encroachment of open land, and the use of insecticides.
Population trend
Currently classified as 'least concern' in Germany (Red List 2016), however, local declines are observed in intensively used agricultural landscapes.