Welcome to the Orchid Board! Those are beautiful flowers!
It could be any of many different Oncidium alliance hybrids. Some may be seedlings that never received names. I would suggest you try to send a photo to Matsui, and tell them where you bought it. They might be able to give you a name.
As for the care, it would need standard Oncidium hybrid care. You can read about that here in the Oncidium forum.
__________________ May the bridges I've burned light my way.
Probably Oncostele Catatante, or a cross with it. Many clones and seedlings of that cross have been used in the grocery market orchid trade so it may not be an exact match for any picture you compare it to. Definitely that type of breeding though, so pretty typical Oncid intergeneric culture, but happiest if nights cool off.