Kasai Rex is a dangerous animal claimed to be a carnivorous living dinosaur in Africa. There are conflicting descriptions of it, and the only original reports are suspected by most cryptozoologists to be dubious.
Kasai valley report
In 1932, John Johnson (sometimes spelled Johanson), a Swedish plantation owner, was traveling with a servant in the Kasai valley, in the Belgian Congo (now Democratic Republic of the Congo). They encountered a rhinoceros, and, while attempting to pass it without detection, were surprised by a large creature rushing out of the undergrowth and attacking the rhinoceros. The servant ran away and Johnson fainted. He awoke to see that the creature was eating the rhinoceros. "It was reddish in color, with blackish-colored stripes," he later said "It had a long snout and numerous teeth.". He decided that the creature, 13 m (43 ft) long, was a Tyrannosaurus. He also said "The legs were thick; it reminded me of a lion, built for speed".
There is a similar story in an edition of the Rhodesia Herald, also from 1932, albeit accompanied by an obviously hoaxed photo, it is probably untrue:
"On February 16 last I went on a shooting trip, accompanied by my gunbearer. I had only a Winchester for small game, not expecting anything big. At 2 p.m. I had reached the Kasai valley (sic)."
"No game was in sight. As we were going down to the water, the boy suddenly called out "elephants". It appeared that two giant bulls were almost hidden by the jungle. About 50 yards away from them I saw something incredible - a monster, about 16 yards in length, with a lizard's head and tail. I closed my eyes and reopened them. There could be no doubt about it, the animal was still there. My boy cowered in the grass whimpering."
"I was shaken by the hunting-fever. My teeth rattled with fear. Three times I snapped; only one attempt came out well. Suddenly the monster vanished, with a remarkably rapid movement. It took me some time to recover. Alongside me the boy prayed and cried. I lifted him up, pushed him along and made him follow me home. On the way we had to transverse a big swamp. Progress was slow, for my limbs were still half-paralyzed with fear. There in the swamp, the huge lizard appeared once more, tearing lumps from a dead rhino. It was covered in ooze. I was only about 25 yards away."
"It was simply terrifying. The boy had taken French leave, carrying the rifle with him. At first I was careful not to stir, then I thought of my camera. I could hear the crunching of rhino bones in the lizard's mouth. Just as I clicked, it jumped into deep water."
"The experience was too much for my nervous system. Completely exhausted, I sank down behind the bush that had given me shelter. Blackness reigned before my eyes. The animal's phenomenally rapid motion was the most awe-inspiring thing I have ever seen."
"I must have looked like one demented, when at last I regained camp. Metcalfe, who is the boss there, said I approached him, waving the camera about in a silly way and emitting unintelligible sounds. I dare say I did. For eight days I lay in a fever, unconscious nearly all the time."
This story presents problems due to inaccuracies. The hunter claims that "giant bull" elephants were in the jungle - yet forest elephants Loxodonta cyclotis are smaller than the familiar elephant L. africana of the plains. A large bull L. africana would have great difficulty in jungle terrain Though, considering the size of all elephants, it is reasonable that the Elephant could still have been described as large.
There is also the similarity between many aspects of these two stories: the single servant runs off; the bloodthirsty creature eats a rhinoceros; and both Johanson and Johnson faint. This suggests a single source for both stories.
Of all cryptids reported from Africa, it is perhaps notable that this is the only one without a unique name in a local language. A carnivorous animal of this size would not have escaped a unique name by the local population.
Two photographs from the first two sightings are said to exist, each showing radical differences from the other. One shows a creature resembling a large monitor lizard. In this photograph, a white line surrounds the creature; it appears to be a cutout from a nature magazine. The other photograph depicts a carnivorous dinosaur-like creature (resembling a Tyrannosaurus) eating a rhinoceros.