SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5f415c3f8762a8a43350346bfd3d19e24fe9381d1cf17869eda6f10eb1487fd8' 
  AND token = 'dYMudXMmMPYwDLltdEx4xhtF6+8mGzvvS8mbZiHPEEY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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