SELECT 
  1 
FROM 
  vi_lock_keys 
WHERE 
  key_id = 'a15e2ea2d39cc8b3f272dedcab5dc070e4dfcf176b8a6ede9707e888024e5f6a' 
  AND token = '6Bh+BwZIrgKOX2xj3tVSSDq24PYAbNS5flsZeBs7uVg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00010

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}