Where does “comaco” come from?

comaco (Occitan) comes from Ido aquo, from Esperanto akvo, from Italian acqua, from Latin aqua, from Proto-Italic akʷā, from Proto-Indo-European h₂ekʷeh₂ — water, flowing water.

Ancestry of “comaco”, step by step

Step	Language	Word	Meaning
1	Ido	aquo	water
2	Esperanto	akvo	water
3	Italian	acqua	water; lane; inflection of acquare: ##...
4	Latin	aqua	water
5	Proto-Italic	akʷā	water
6	Proto-Indo-European	h₂ekʷeh₂	water, flowing water

Every word from Proto-Indo-European h₂ekʷeh₂ →Every word from Proto-Italic akʷā →Every word from Latin aqua →