I have frequently seen the two crocodiles on this coin identified as saltwater crocodiles (Crocodylus porosus). But that appears to be only half right. According to Mr L Wilson Kamit, CBE, Governor of the Bank of Papua New Guinea, the coin represents both the saltwater crocodile and the fresh water crocodile a.k.a. the New Guinea crocodile (Crocodylus novaeguineae). In the same speech, at the link below, we find out that the Minister of Finance named his son Toea after another denomination of New Guinea currency. (100 Toea = 1 Kina).
https://www.bis.org/review/r081124e.pdf
I'll upload a scan if I can figure out how to do it.