Bird Dropping Spider - Celaenia excavata

The spider has evolved an effective strategy against being eaten by day-active predators such as birds and wasps. Its body mimics unappetising bird droppings. They are dirty white, grey and black in colour, with very large abdomen. Bird-dropping Spiders are sometimes called Bird Dung Spiders. They are also known as Orchard Spiders because they are so commonly seen in citrus and other orchards.
https://www.brisbaneinsects.com/brisbane_orbweavers/BirdDroppingSpider.htm