If it is flat on the bottom and looks like a little half shell stuck to the leafs surface it is probably the protective covering over a scale insects eggs. I would spray your plant down with Palmolive dish soap (a few drops in a bottle of water) or alcohol. Scale can sometimes be a problem on Hoyas but they are easier to deal with than mealy bugs.

Mike

thats exactly what it looks like, thats what it mist be...

I swear I posted a comment a few minutes ago, that it looks like a piece of Osmocote (time released fertilizer) to me.

I can magnify the photo in my computer and it looks exactly like a scale insects egg mass. If you crush it there will be a tiny amount of white powdery material. The young will have already left but they may have also already been killed off if pesticides were applied. Did this plant come from a commercial greenhouse?
Just watch any new growth very closely for the crawlers and wipe them off if you find any.

Mike

i was just looking around and i think it looks a lot like a citrus mealybugs egg mass... heres the pic i found and it looked a lot like whats in this pic...

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Source: Uploaded by user via Amber on Pinterest

Definitely not a mealy bug egg mass. Melay bug egg masses are protected in a white cottony substance. The photo you have above shows an adult mealy bug, an immature bug, and some crawlers which are the newly hatched yellow ones.

Scale insets have a shell that protects them and the same shell also protects their eggs. Don't worry about what type of scale insects they may be, they are all dealt with the same way. Different areas of the country have different species and many are specific to certain plant families while others are widespread.

Mike

Here is a link that might be useful: Scale insects

ok thanks so much for the help, im just hoping that i can get rid of them so that my mothers day presents dont all die, i got 4 different hoyas for mothers day (they are quite small) and im just hoping that my mothers day presents stay alive

Your plants will be fine, especially if there were only a few insects. A serious infestation leaves the plant absolutely covered in scale and that can weaken a plant but a few is nothing to worry about.
One thing is for sure, if you grow Hoyas you will learn about insect pests!

Let us know if you have any other problems with your plants. For now alcohol and a Q-tip along with a little time once a week will go a long way.

Mike