You are allowed to be confused about the plural.
It should be platypodes, but almost nobody uses that term.
There is no universally agreed plural of "platypus" in the English language. Scientists generally use "platypuses" or simply "platypus". Colloquially, the term "platypi" is also used for the plural, although this is technically incorrect and a form of pseudo-Latin; the correct Greek plural would be "platypodes".
https://en.wikipedia.org/wiki/Platypus



				
				
				
				
				
			

				


Bookmarks