Lava bed melon on Big Island???

[JeepCA]

I was hiking on a new and very sparse lava bed in Hawaii (Big Island) when I found this plant. It has leaves and tendrils simiar

View attachment 24894 View attachment 24894 View attachment 24894 to a pumpkin) and some sort of fruit.

 

[Larisa]

Welcome, @JeepCA !
This is a Cucumis dipsaceus (or Hedgehog cucumber).
Origin - Africa. In other countries it is naturalized.

 

[JeepCA]

After doing more research I found this is an invasive spp to Oahu and the Big Island. They have been use moths as a biocontrol of this plants.

 

[Marck]

Teasel Gourd (Cucumis dipsaceus), also known as Hedgehog Cucumber, is a member of the Gourd Family (Cucurbitaceae) native to eastern Africa, but now also a weed in Hawaii and various parts of the New World, including Texas and the Galapagos.
It is considered an annual, though in a tropical climate that will likely vary. The fruit are edible, but obviously more difficult to peel than those of the common cucumber (Cucumis sativus).

Here is an amusing photo of how rampantly this vine grows in Hawaii.
http://www.starrenvironmental.com/images/image/?q=50338040601