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What are the hilum and micropyle on a mature seed coat?

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A pangolin walks through grass with a blue circle around it and the word endangered written in white across the image. — Integument The pangolin is the only mammal in the world covered in scales.

On a mature seed coat, the hilum and micropyle are distinct features related to the seed's development and attachment:

Hilum: This is a small scar on the surface of a liberated seed that marks its former point of attachment to the funiculus, or seed stalk, within the fruit.1
Micropyle: This is a small opening in the seed coat that persists from the ovule. In the original ovule, it served as the site near which the egg cell was situated.1

These structures are part of the seed coat, or testa, which is derived from the protective integuments of the ovule. While the hilum serves as a structural scar, the micropyle may remain as a small pore in the mature seed.1