Sexing Paradise Fish

[wrightt3]

I recently picked up a paradise fish but am unsure how to determine whether it male or female. If anyone has any advise then that would be great.
 
Also just out of interest, are they a actually type of gourami as they are sometimes advertised or are they their own species?

 

[DreamertK]

 
http/www.seriouslyfish.com/species/macropodus-opercularis/
 
The male is far more colourful than the female and develops striking fin extensions at maturity.
 
Like many anabantoids, it’s a bubble-nesting species. Intraspecific aggression is particularly pronounced with this species. While juveniles may be seen swimming together in dealers’ tanks, this is not a fish that exists in groups by nature. When males arrive at sexual maturity they become highly aggressive towards one another and will often fight until only one remains. Certainly only keep a single male in tanks measuring less than 4′/120cm long. Females tend to be far less belligerent and can be kept in small groups if you wish.

 
Left - female. Right - male.