Signature Spider Stabilimentum

This is a female Argiope luzona. If you look closely, you can just see a small prey item, wrapped in silk, in its mouth. Its web decoration is known as a Stabilimentum (the Latin word for a "support"). Wikipedia states that " Its function is a subject of debate". In modern thinking, the stabilimentum (which is known to reflect ultra-violet light) might be used to attract prey to the web or, possibly, to make the web more visible to larger animals so that they can avoid crashing into it. This particular type of Stabilimentum is called a "Three-armed Discontinuous Cruciate Stabilimentum".