SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c469266347e6d6ae8012236aa6ce5d42ce627ae1fe58eaa4e7cea6250b865b10' 
  AND token = 'jp9JO1rFXa0zFQBAkulGOMpROCSSIUiAtpJw47FtMVs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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