User blog comment:Kogath/Monster Hunter 4 Ultimate for the Nintendo 3DS/@comment-6050823-20140824193636/@comment-6050823-20140825234506

The monster genders can be quite confusing but are pretty easy to remember(At least for some of us). We know that female Diablos are generally larger than males, some of the HC Monsters like the HC Tigrexs and HC Gogomoas are males, most of the Duramboros we hunt are males from them being solitary while the females live in herds with their young, and that some monsters reproduce asexually like Gigginox(Khezus at a time did reproduce sexually until there was many defects in their species which are white in color).

On a side note, all three Nargacugas are different species and the UNKNOWNs can be both males or females.