Watching Avengers: Infinity War, we see Gamora and her mother. There's also a bunch of people during a flashback on her home planet, who all look female--maybe there's a quick glimpse of some males, but I'm not sure. There seems to be very few males on that planet, if any.

Does Gamora's species have males?

I'm hoping for an unequivocal answer (e.g. details of Gamora's biological father), not just a quick glimpse at some scene where I'm left thinking "maybe they're male".

In the comics (Gamora Vol 1 #4), some male Zen-Whoberis/Zehoberei are shown:

They are the same species as Gamora, who is shown in the middle. It's also worth mentioning that Gamora calls them her "relatives".

In the movie canon, what Gamora says in Guardians of the Galaxy Vol 1 heavily implies she has a birth father:

Gamora: My father didn't stress diplomacy.
Peter Quill: Thanos?
Gamora: He's not my father. When Thanos took my home world, he killed my parents in front of me. He tortured me, turned me into a weapon. When he said he was going to destroy an entire planet for Ronan, I...I couldn't stand by and...

Yes

Watching the scene where Thanos takes Gamora we see what appear to be males of her species in the background. This guy in the background appears to be one (ignore the giant watermark I couldn't find a better video easily):

Gamora is a member of the Zehoberei, who live on the planet Zen-Whoberi. By all Marvel sources, the Zehoberei are a humanoid race. They have children, which would indicate that there are both male and female Zehoberei necessary for procreation.