Please have a look at this link.

https://books.google.co.in/books?id=fiINKSiT0eUC&pg=PA624&lpg=PA624&dq=how+seeds+are+dispersed+in+citrullus+colocynthis&source=bl&ots=G27lbDc5oq&sig=XrKwsQarjeiGU-mIjaswOasqzec&hl=en&sa=X&ved=0ahUKEwiksJLl-L7QAhXKQ48KHSDXBTMQ6AEITjAJ#v=onepage&q=how%20seeds%20are%20dispersed%20in%20citrullus%20colocynthis&f=false

Dear Dr. Singh,

Thank you very much!

It means that my thought was in the right way.

Greetings from Würzburg,

Amauri.

As with all fruit seeds, Citrullus colocynthis uses animals to disperse seeds. When an animal eats Citrullus colocynthis, the seeds generally pass through the digestive system and are dispersed :-)

Dear Dr. Pegman,

Could you give an example of animal which feeds on C. colocynthis?

Best wishes from Würzburg,

Amauri.

Not sure about animals (which ones ? come on guys !) and likely not much  ... except the gazelles / Oryx (very few left ...) eating the dry fruits when nothing else is left in arid zones of North Africa and the Middle-East to Mongolia  ... but most of the Citrullus colocynthis grow in wadi and depressions ...hence seeds are often carried away by running water during winter - Mediterranean winter >>>> also , during parching summer, the light dry fruits are rolling far away with the strong desert and steppe winds ........my experience in these parts of the World !

Rgds

Gus 

Thank you very much Dr. Gintzburger for sharing your experiences! The dispersal by wind I got a reference but nothing about water or animals.

.... by wind ... little seed dispersal of Citrullus by wind, but mostly transported away by water in wadi when water runs during winter.   Small round fruits rolls away with wind. ... i have not seen any papers on this subject.

Gazellles and Jerboa eat the dry fruits (when green they are very bitter) and possibly disperse the seeds  

Regards

Gus    

I concur with Gus!

That is all I have found (see the link in the first answer for this question): "The seeds are dispersed when the fleshy fruits have dried out and are blown about by the wind"

Cunningham et al. 2011. Plants of Western New South Wales. Csiro Publishing, Collingwood, Australia.

Field of interest rather than field of expertise. Look at Wikipedia for Cittrullus lanatus.

Your species is clearly related to the desert "Tsamma" used for water by man and animal during times of drought in Sub-Saharan Africa. The seeds are widely dispersed by trekking animals during migration and after long droughts. It was also carried by early man as a handy "storage container" for water. Wikipedia discusses the confusion with the naming of species such as the "common water melon", "karkoer or wild melon" and "Tsamma. It would be advisable to do DNA-testing to clarify inter-species relationships with your species. Young Citrullus lannatus is typically variegated when young, but turns the same light yellow as your species when they are old and dry.

Hi Amauri. I am interested in seed dispersal of C. colocynthis. Did you get any fiurhter nformation (especially on seed dipersal by animals) that ciould share ?

Gratefully,

Jose

Hi Jose M. Fedriani, apologies for my late reply. I ended up with the information that the dried fruits are blown about by the wind. None extra info on zoochory.

Greetings from Würzburg,

Gazels (and Sheep, camels, Goats) eat the dry fruit (not the green one) and may contribute to seed dispersion. No ref in literature but have seen this in North Africa, the Middle-East and Central Asia arid zones.

Seeds can be dispersed by animals after being eating dry fruits (goats and camel) or when the fruit is broken and rattled by animals.

Citrullus spp is very important as "water" supply to wild desert herbivores such as addax. Nomads in north-western Sudan intentionally drive their sheep flocks to graze areas where the plant is common so their animals can withstand extremely long watering intervals: 1 month! So seed are dispersed with sheep faeces.