SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '72f2a494fd40464fda10084ac1aa96285cef1c380b5c358fbadb493f74c8bad5' 
  AND token = 'Hrw99AWoOtBB8DKBxCEerb7ASjur5TR+xzHqIdh5mfo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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