SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b5a9ed90e62bece545cd9abf76ad5daa9563a0d7d89b30f697bc74bea68e198f' 
  AND token = 'zQl65QEXoJLsDcaqLwg9TGaZSDDrB/q6Iv0cWTHpEV0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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