Asian Spinybacked Orbweaver

thelacantha brevispina

The Asian Spinybacked Orbweaver (Thelacantha brevispina) is a captivating spider renowned for its striking, crab-like appearance. Widespread across South and Southeast Asia, this small arachnid stands out due to its hardened, colorful abdomen adorned with six prominent, sharp spines. Unlike typical garden spiders, the females of this species build highly robust, vertical orb webs decorated with conspicuous white silk tufts, which may serve as a visual warning to prevent birds from flying through them. These industrious spiders are major insect predators, playing an essential role in regulating local pest populations in tropical forests, gardens, and shrubby areas. While their bizarre shape and vivid markings can make them look intimidating, they are completely harmless to humans. Take the ultimate field guide with you and identify Asian Spinybacked Orbweaver using the Snappit app.

Habitat: Found in tropical and subtropical woodlands, scrublands, and coastal forests, frequently weaving webs between shrubs and low tree branches.

Appearance

Female Asian Spinybacked Orbweavers possess a broad, hard, crab-like abdomen that features a distinctive pattern of white, black, and orange markings, punctuated by six distinct, dark spines curving outward from the edges. The abdomen's dorsal side often displays two prominent white spots resembling eyes, contrasting sharply with the dark background. Females measure around 0.5 to 1.0 centimeter in length, whereas the cryptic males are significantly smaller, often measuring less than 0.3 centimeters, and lack the dramatic spines and bright coloration of their female counterparts.

KingdomAnimaliaPhylumArthropodaClassArachnidaOrderAraneaeFamilyAraneidaeGenusThelacantha

Asian Spinybacked Orbweaver

Interesting facts

Males are extreme underdogs in size, weighing up to 100 times less than females, and must carefully court females to avoid being eaten during mating.

The distinct 'eyespot' pattern on the back of the spider's abdomen is a form of mimicry designed to confuse and scare away potential predators.

They rebuild or patch their webs almost daily to ensure the sticky silk remains effective at trapping prey in dusty tropical environments.

Special abilities

The hardened abdominal exoskeleton and sharp spines make the spider difficult and unpalatable for small predators like birds and lizards to swallow.

They weave highly visible white silk tufts into their webs, which act as visual deterrents to prevent larger animals from accidentally destroying their hard work.

They can adjust their body orientation relative to the sun to absorb heat on cooler mornings or minimize direct exposure during intense tropical afternoons.