I just realized that 2 of the previous shrimp I bought may not be “true” Amano Shrimp.
Basically, they lack the distinctive dots / dashes of true Amano shrimp. See also this site on an example of fake Amano shrimp: https://www.plantedtank.net/forums/88-shrimp-other-invertebrates/570946-amanos-born-their-side-top-markings.html
You can also see the shrimp in my YouTube video (around 2m 43s mark):
Despite it being an “imposter”, it behaved quite similar to Amano shrimp, eating algae and cleaning up the tank. According to some online sources, it could be Malayan shrimp which is also quite probable due to the locality (Malaysia is just next to Singapore). Malayan shrimp have different colors, and the clear colored ones look very much like Amano or Yamato shrimp.
Disappearing / Missing Shrimp
What is interesting about this shrimp (fake Amano) is that it totally disappeared from my fish tanks — twice. The first time, it disappeared from an open tank with just neon tetras in them. The second time (another shrimp of the same type), it totally disappeared from a close lid tank with just a honey gourami and 2 horned nerite snails. I did not find their body anywhere inside or outside the tank.
What I suspect is that they died soon after molting (I did see them molt), and then got totally eaten up by the small fish as shrimp sashimi. Or possibly they have a very fast rate of decomposition and can essentially “dissolve” into the water overnight.