Coat of arms of  João de Castro Canto e Mello, 1st viscount of Castro (the same arms of the Portuguese blasons of the Canto and Castro families). Also used by his offspring, the 2nd viscount of Castro and the marchioness of Santos.
Archivo Nobiliarchico Brasileiro, of Rodolfo Smith de Vasconcelos and Jaime Smith de Vasconcelos (1918).
myself, based on symbol of XIX century.