Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eb3aa3a6c9bcf973595d0900486dbc2d2aefe7076cddb24f536a28d8b0bb8cd7' 
  AND token = 'kupNZYAJFTQnWXLDGXBw34WStUwo1LcsYZuFt2+U7Hc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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