Namibia / yellow flower climbing or crawling

Hello,

Here is a yellow flower seen in Namibia / Etosha national parc / Halali camp waterhole during the rainy season.
It was growing on the side of the track leading to the waterhole and I haven't seen any other in another place. The plant climbs on other plants or crawls on the ground.
I was asking myself if it could be an invasive plant.
Does someone knows its name ?
Thank you
Cheers

 

It makes me think of Thunbergia, but the petals look too skinny. Leaves, habit and location seem to fit.

 

Hello Wendy,

Indeed, the thunbergia petals are bigger.
We'll see if someone has another clue
Cheers

 

Family Cucurbitaceae - perhaps a species of Momordica? (not all species have strongly lobed leaves)

 

Hello Tony,

Following your track, I have been through the momordica species I could find, but unfortunatly I haven't found pictures of them all on the web.

Kirkii and boivinii flowers were the closest in my search but the leaves are different.
I'll continue to search if I can find complementary images or descriptions.

Thank you very much for this very good help
Cheers