SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8bf527578771ff24908aac23d6c4ca454e559a8ac42b74c43611adf1ce63b70c' 
  AND token = 'ozp7k0Mu+09vs3yu58iLWpKp3GHU56SzApFx0lrnkBI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}