The top 25 most endangered primates, and the hotspots where they are found, are:

Madagascar and Indian Ocean Islands Hotspot:

(1) the golden bamboo lemur,
(2) the Lac Alaotra bamboo lemur,
(3) Perrier's sifaka,
(4) the silky sifaka and
(5) the golden-crowned sifaka

Atlantic Forest Region Hotspot:

(6) the golden lion tamarin,
(7) the black lion tamarin,
(8) the black-faced lion tamarin,
(9) the buff-headed capuchin and
(10) the northern muriqui

Tropical Andes Hotspot:

(11)the yellow-tailed woolly monkey

Guinean Forests of West Africa Hotspot:

(12) Miss Waldron's red colobus,
(13) white-naped mangabey,
(14) Sclater's guenon,
(15) the drill and
(16) the Cross River gorilla

Eastern Arc Mountains and Coastal Forests of Tanzania and Kenya Hotspot:

(17) Sanje mangabey

Indo-Burma Hotspot:

(18) Delacour's langur,
(19) Cat Ba Island golden-headed langur,
(20) gray-shanked douc langur,
(21) the Tonkin snub-nosed monkey and
(22) the Hainan gibbon

Sundaland Hotspot:

(23) the Sumatran orangutan and
(24) the Javan gibbon

Democratic Republic of the Congo, Rwanda and Uganda (not among the hotspots):

(25) the mountain gorilla