Well, like I said - I can't be certain.
Ada.dec. is a valid option too.
Many species have "all black" first instar larvae, although on closer inspection they often appear to be more brownish or blueish or so - to the casual observer they'll just seem black.
Colour changes a lot though, even throughout each stage. When just shedded they have fairly light/bright colours and it will take a few hours for the "typical" colours to settle in again. Towards the end of each instar, just before shedding, colours seem to get less "hard" again, almost "smokey"/"pastel" or even transparent at times. And of course the definite colour pattern most people know/recognize from the 4th instar larvae only develops slowly.
In this image the hatchlings are quite fresh (light coloured still), they will become dark black and then gradually "puff up" to the almost whitish late instar 1 larva (2nd row left). The typical colour pattern for the
Har.axy. I4 larva is quite slow to develop and until well into the 3rd instar these can still easily be confused with the native
Har.qua. larvae.
Best character for telling the "little black jobs" apart is the size & shape of the "brushes". From one of your silhouettes I got a hint of a
Harmonia impression and
Har.qua. would be on "needles" not leaves - so
Har.axy. But the image is really not good enough and even from much better images the whole thing (ID of 1st/2nd instars) is quite "iffy". Brushes on
Adalia are much shorter than
Harmonia (and a different shape), but on 1st instars they seem relatively large/prominent - much more so than on older instars. So, can't really 100% rule out
Adalia or even some other genus.
Cheers, Arp