Portulaca oleracea

Portulaca oleracea (common purslane, also known as little hogweed, or pursley) is an annual (actually tropical perennial in USDA growing zones 10–11) succulent in the family Portulacaceae.

The plant may reach 40 centimetres (16 inches) in height. It has smooth, reddish, mostly prostrate stems, and the leaves, which may be alternate or opposite, are clustered at stem joints and ends. The yellow flowers have five regular parts and are up to 6 millimetres (1⁄4 inch) wide. Depending upon rainfall, the flowers appear at any time during the year. The flowers open singly at the center of the leaf cluster for only a few hours on sunny mornings. The tiny seeds are formed in a pod that opens when the seeds mature. Purslane has a taproot with fibrous secondary roots and can tolerate poor soil and drought.

Purslane has an extensive distribution, assumed to be mostly anthropogenic (or hemerochoric), extending from North Africa and Southern Europe through the Middle East and the Indian subcontinent to Malesia and Australasia.

From Wikipedia