Spanish is apparently like English in that there are a multitude of words for horses.
In English, we have "colt", "equine", "filly" (female), "horse", "mare" (female), "mount", "stallion" (male), and "steed".
In Spanish, I've found "caballo", "corcel", "equino", "montura", "padrillo" (male), "protranco", "potro", "semental" (male), and "yegua" (female).
The clearly gendered terms aside, my questions are:
(1) Which of the remaining terms allow gendered forms? Can I use "caballa"/"caballo", "equina"/"equino", "montura"/"monturo", etc?
(2) Which of the remaining terms allow gendered articles? Can I use "el caballo"/"la caballo", "el corcel"/"la corcel", "el equino"/"la equino", "el montura"/"la montura", etc?
If SpanishDict is any indication, "potra", "potranca", "potro", and "potranco" are all valid terms, so I guess they don't need any explanation; see http://www.spanishdict.com/translate/potro and http://www.spanishdict.com/translate/potranco.
I've seen indications that terms like "caballa" are never valid (to refer to a horse, not a fish) in any circumstance, however, and it's not clear to me whether I can still use "la caballo" if that's the case.