Here is a bit more information including the names for their new finding(s):

In the pictures that New Horizon’s took of the Southern edge of Sputnik Platina, two volcano features have been spotted. They’ve been informally named Wright and Piccard Mons (I’ve been reliably informed that ‘Piccard’ is in reference to August Piccard the physicist and explorer).

It is early days in the discovery, but as Dr Oliver White, one of team of scientists looking through New Horizon’s data, said ‘These are big mountains with a large hole in their summit, and on Earth that generally means one thing – a volcano”.

If this turns out to be a fact, it will likely change a lot of what we thought we knew about planetary surfaces and geology.

Congrats to the team and we are looking forward to hearing more as they have more time to study this data.

thanks to iflscience.com for the great info

thanks to NASA for the pics