SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5b59ee3eda69bf901b3e843c54b6af26a2b698e52ec5618733b8c764355bb758' 
  AND token = 'C025Ygf00ZJi0LaWrzhBvRs7quTj5Kh3atnGBx+rpO8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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