Araneus trifolium, commonly known as the shamrock spider, is a species of orb-weaving spider found in North America. It is named after its distinctive web pattern, which resembles a three-leaf clover or shamrock. The spider has a round abdomen with a yellow or orange coloration and can reach a body length of about 1 cm. Araneus trifolium is known for its skill in constructing intricate webs to capture prey.