What genus are these?

[estación seca]

I would agree it's an intergeneric Oncidium hybrid. Often tall, narrow pseudobulbs in this group are from Brassia ancestry, indicating more warmth tolerance than in some other hybrids.

Care is easy in most homes. They prefer to stay always moist. Bright light is best, but they don't need as much light as do Cattleyas or Vandas. Many complex hybrids can make new growths multiple times per year, which also means flowering multiple times per year.