The bulbs are damaged by tarsonmid mites (Steneotarsonemus laticeps, barely visible, 0.2 mm) then the sitches are infected with red blotch, Stagonospora curtissi.
Rotting material attracts these fingus gnats you are observing now.
So, these are only the 3rd element within the chain of reasons and effects.
The translucent maggots of these "mosquitos" can indeed become harmfull by themselves namely if get access to seedlings. Even fully intact seedlings might become substantially consumed by these little critters.

Please consult your local plant protection bureau and ask for legal means against tarsonemid mites on amaryllis. bulbs. Insist on protection of the growing crop; not the hot water treatment.

OOOPS
FUNGUS GNAT is the correct term.

Hans, I have searched around the internet, but cannot find a reference to or the definition of "sitches". Please help.

-Carol

Oh NOOO.... *ggg*
Sorry for the inconveniences...
I meant "stitches" namely the injection points of the mites. The damaged points form needle-sharp streaks on the affected plant tissue. I had several occasions to see that exactly on these lines subsequent red blotch is forming.

Hans Werner

I am familiar with the mites, but these worms are over a centimeter in length and their bodies are see-through. I am not sure if the bulbs have been damaged by the mites. I do not observe any leaf damage like the type in a photo you recently posted.

Plant_Guy

I believe Lora mentioned it here about using BT (bacteria) for seed beds. I've been using it and it seems to work. I actually did see one of those little worms dig to the surface after I was just spraying it on the surface. Now I just bottom water and dunk the Rubbermaid container of seeds into the bacteria water and it supposedly wrecks havoc on the worm's digestive system. Here are a couple threads where they seemed to work here and here.

Hi Plant_Guy,
Yes,those are fungus gnats and their larve that you are seeing. They spread like wildfire so treat all of your plants. I think Bt works best,especialy for inside use. I just put a mosquito dunk in my watering can. It dissolves slowly and lasts a very long time. Lora

Thanks for the suggestions. I used a bulb drench from a local nursery. Smells reaaly bad, just like nail polish. After first treatment, I didn't see any gnats or worms. Will apply second treatment a week after the first. The pot where the troulble started is outside, those bulbs are a total loss.

Plant_Guy

Scaarrrryyyyyy....just thinking about it! So would it be wise to spray/drench this Bt or mosquito dunk on all you Amaryllis (mature and seedlings) as a preventive? If yes, how often?