Does this mean no more hydrus pets?

For the time being, yes. I highly doubt they would just put an abrupt end to Hydrus pets in general, but since Merana is MIA right now, they're unavailable.

staff commented in the News post's Comment section that Hydrus is not available right now, with 'right now' bolded. I interpret this to mean that sometime in the future, it will be available again.

Clicking her temple doesn't seem to do anything, so FWIW she's not around to curse your pet right now.

NPC Shinwa's epic weeklong Phiphunnertt II and Fife Afore spells worked on me, one of Merana's strongest supporters, My pets barely fought at all in the big guardian challenge before succumbing to the Evil's Despair part of her magic Her spells did work, after a fashion.

She didn't account for the general avariciousness of the average Jane non-human-sacrificing Subetan, though. Mwa ha haa!

(My memory is that before she died folks really hated Amy and her quest so I'm all ??? about that development, TBH )

The Hydrus Curse shall rise again bigger and better than before!

Oh dang, I wish I had known this earlier D: I just changed my Hydrus Paralix to the Nostalgic one, thinking I could make my Kerubi a Hydrus pet instead. Oh well. Guess I have to wait;