SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1fc0dacc28f1eeeb6a9704d38511d970ad97625a311bfe23a715a8afafdad242' 
  AND token = '+hlniGtac0i5sfRToVdA//I4YLFH1J+cImbRvL4Fo7M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00058

JSON explain

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