"The owl sees Neptunus."
Translation:Bubo Neptunum videt.
But, is "noctula" classical Latin as the course is supposed to be?
It's the modern Latin name of the Athena/Minerva's owl "Athene noctua" (the little owl), the science name, but not the classical name.
The noctula is also a bat (Nyctalus noctula) (the common noctule), and several species of butterflies. If we consider "noctula" alone, it's rather the bat in our modern language, not the owl, and in classical Latin, it was not "noctula" but "bubo", like in "Bubo Minervae", so they shouldn't accept "noctula" in this course.
Translation of Names
A little convention: we will not accept translations of names as alternatives in this course. Marcus's name is Marcus, not Mark, and Stephanus is not Stephen or Steven.
The names of gods are not in the same category as given names shared by multiple individuals. "Neptunus" is the name of a unique entity, and in English the name of this entity is "Neptune" (just as "Roma" is known as "Rome"). Duolingo's policy on god's names is quirky - though that doesn't interfere with my enjoyment of the lessons.