English English Black ghost knifefish English English English English Wikipedia http://en.wikipedia.org/wiki/Black_ghost_knifefish English black ghost knife ویکی‌پدیا انگلیسی English Black ghost knifefish Black ghost knifefish English English the animal I do research on English English English English Black ghost knifefish English Black ghost knifefish English English English English English Black ghost knifefish