Difference between Asiatic and African lion
In appearance, the differences between Asiatic and African lions are slight. They are subspecies of the lion.
I will quote verbatim from Fiona Sunquist in Wild Cats of the World who referred to two sources:
- R. I. Pocock – The fauna of British India, including Ceylon and Burma Vol 1 Mammalia – 1939 and;
- G.B. Schaller – Serengeti lion 1972

Comparing the African and Asiatic lion. Photo left: Houston Zoo. Right: Wikipedia. Montage: PoC.
“The Asiatic lion has a pronounced belly fold, a flap of skin that runs the length of the belly between the front and hind legs. This fold of skin is almost always present in Asiatic lions, but rarely seen in African lions. Asiatic lions also have a thicker coat, longer tail tassel, and a scantier mane (for males)”.
The internet tells me that Asiatic lions are slightly smaller than their Africa cousins.
Of course they live in different parts of the world. The Africa lion lives in sub-Saharan Africa while the Asiatic lion lives in and around the Gir Forest of northwestern India.

Lion distribution 2019. Annotations: mainly PoC. Map: Wikipedia.
There are about 400 Asiatic lions and 20,000 African lions. The Asiatic lion population size is somewhat static due to desperate conservation measures as the sustainable population limit has been reached. In contrast the wild African lion population continues to decline quite rapidly due to human interventions including habitat loss, farmer retaliations and sport hunting (although hunters claim revenue from sport hunting aids conservation). African lions are bred for canned hunting in South Africa and this population is stable as I understand it.
SOME MORE ON THE ASIATIC LION (and African lion because there is an overlap):

Video of Asiatic lion in Gujarat, India
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Do lions eat grass? Yes.
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How long can lions go without water?
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Do lions eat other lions?
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What is the social organisation of lions?
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Lion habitat – ‘at home in more open areas’
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What cats live in groups? 3 felids do it.
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