I think the word you're looking for is "acknowledg(e)ment".

10) ¿Cuáles son las formas legales de reconocimiento de un hijo en Honduras?
R.- Las formas legales son las siguientes:
• Por comparecencia personal del padre o madre o ambos al
inscribir a su hijo en el Registro Civil Municipal.
http://www.rnp.hn/wp-content/uploads/2011/02/preguntas_mas_f...

Q. What is voluntary paternity acknowledgment?

A. Voluntary paternity acknowledgment is a simple civil process that can be used to legally establish paternity for a child born to unmarried parents. It is a way to establish the father-child relationship without court involvement. The process is completely voluntary and is meant to be used by parents who are sure who the biological father is.
https://www.nd.gov/dhs/services/childsupport/faq/faq-vpa.htm...

I'm assuming "legal" means that this note is required by law, hence "statutory", but I suppose it might instead mean that it was made "lawfully".

I'm not sure how "aparece" relates to the rest of your text, but if this is a certified copy of an original birth entry it might just be stating that the original contains that marginal note, so:
"A statutory marginal note of acknowledgment appears here" or something to that effect.