SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5a25445ee1c725c8e0e8b987863e45d5890ae74c801cfad4c3ec10a07d649582' 
  AND token = 'OVCIkGo9gwloDlZgyVPYIq8/mc5hUe+kppVI6OtcNUQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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