With the demise fo the 45-year-old rhino, who passed away from "age-related complications", hope for the survival of the Northern White Rhino diminished even further: the two remaining members of his species are both female and are unable to carry a baby to term.
The final photograph of Sudan shows him being comforted in his last moments by wildlife ranger Zacharia Mutai.
Captured on camera by a National Geographic photographer, it is a reminder of how much we are set to lose if threatened species continue to go extinct.
On Instagram, photographer Ami Vitale was quoted as saying:
With a heavy heart, I share this news and hope that Sudan's legacy will awaken us to protect this magnificent and fragile planet.
Yesterday, Zachariah Mutai comforted Sudan, the last living male Northern White Rhino moments before he passed away.
Despite the tragedy of Sudan's death, a slim hope remains that the sub-species could be saved by artificial reproduction techniques such as in vitro fertilisation.
When Sudan was born in the country now known as South Sudan, Northern White Rhino numbers were still in the hundreds. But poaching in Sudan and parts of central Africa, aggravated by conflict in the regions, drove them to the brink of extinction.
Sudan spent his final years under armed protection against the threat of poaching.
Heather Sohl, chief adviser for wildlife at conservation charity WWF said:
The death of Sudan is heartbreaking. We’re seeing the extinction of the northern white rhino happen right before our eyes, driven by the insatiable demand for their horns.
To ensure other wildlife doesn’t suffer this fate, we need strong action such as cutting demand, cracking down on corruption and improving enforcement.