It may shock you how tiny they are, but I'm sure you have a critter keeper set up for them ala Patrick's care sheet advice. As tiny as the new guys are, they will eat the smaller fruit flies right away.
As a bit of advice I find works for newly aquired froglets: Your imitators may come all in one cup, very carefully packed. Patrick sends larger babies in separate cups. Put the cup down into the nursery, remove the lid and leave it slanted sidewise. Let them decide when to come out and explore. (Don't just dump them in, in other words.) Entice them with a few flies (or springtails, if you have them) and keep them relatively surrounded with obvious food sources after this. They mature fast and will begin calling and breeding in their permanent tank in 5 months or so if you have any pairs. They are athletic and like to explore. They'll be all over the new tank initially, then choose territories on the higher places. They put on a great show.
And I'm excited too. A couple of people cancelled on the waiting list for Pumilio Bastimentos, and Patrick is shipping my frogs tommorow. Then it's a big rush--have to drive 150 miles and back across the desert to meet them at the nearest Airborn Express.
Enjoy your imitators!

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Patty
Lost River, Idaho
D. auratus blue
D. galactonotus
D. imitator
D. leukomelas
D. pumilio Bastimentos (soon)