Vespertine
Etymology
From Latin "vespertinus," from "vesper" (evening), the same root behind the church service "Vespers" and the evening star Hesperus. It survives chiefly in botany and zoology for plants and animals that open or stir at nightfall, but its poetic reach — the whole hush of evening — has kept it alive in literary use.
adjective · /VES-puhr-tyne/
Relating to, occurring in, or active during the evening.
What it names
A rare, precise word for evening things — evening light, evening moods, or flowers and creatures that come alive at dusk.
Example
The garden was planted for vespertine blooms, so its whitest flowers glowed only after sunset.
Related idea
Crepuscular refers to twilight in general, and to creatures active in that half-light; vespertine points specifically to the evening itself.