The BBC reports that the singer died Saturday morning in Madrid surrounded by her family.
Her bandmate Cristina Sevilla wrote on Instagram: “My dear Maria, a wonderful artist, but above all, my friend has left us today.
“I can only thank you so much for how I received from you.”
Baccara experienced an unprecedented success with Yes Sir, I Can Boogie.
The song reached number one in the UK and across much of Europe, eventually selling for as much as 18 million copies – making it the biggest selling single of a female duo of all time.
A clip of Scotland players singing the 1977 disco classic together went viral in the wake of the men’s team that qualified for their first major tournament in 22 years.
“I’m so happy. It was very unexpected. Everyone started calling: journalists, friends, fans, family. Oh my God.
“The phone has been non-stop, but I’m glad it was such fantastic news.”
Baccara broke sales records after the release of Yes Sir, I Can Boogie in the 1970s.
She said: ‘If I had woken up in the morning and someone had told me that this had happened, I would not have said that this was impossible.
“But these guys, the Scottish team, they made it a reality. After 43 years, getting to number three is like a dream come true.
“I found the video of Andy Considine very funny. They are young boys, nice boys, and they have done a great job.
“One of the first things I did was send a thank you note on Instagram to Andy. I had to do it.”