Well I might aswell add my few:
Amazon World, Isle of Wight - August 2017:
1) Grey Mouse Lemur (Microcebus Murinus)
2) Ring-Tailed Lemur (Lemur Catta)
3) Red-Ruffed Lemur (Varecia Rubra)
4) Red-Handed Tamarin (Saguinus Midas)
5) Goeldi's Marmoset (Callimico Goeldii)
6) Common Squirrel Monkey (Saimiri Sciureus)
7) Black-Capped Squirrel Monkey (Saimiri Boliviensis)
8) Grey-Legged Douroucouli (Aotus Lemurinus)
9) White-Faced Saki Monkey (Pithecia Pithecia)
10) Black Howler Monkey (Alouatta Caraya)
Monkey Haven, Isle of Wight - August 2017:
11) Common Marmoset (Callithrix Jacchus)
12) Cotton-Top Tamarin (Saguinus Oedipus)
13) Red-Bellied Tamarin (Saguinus Labiatus)
14) White-Throated Capuchin (Cebus Capucinus)
15) Grivet (Chlorocebus Aethiops)
16) Collared Mangabey (Cercocebus Torquatus)
17) Rhesus Macaque (Macaca Mulatta)
18) Barbary Macaque (Macaca Sylvanus)
19) Javan Langur (Trachypithecus Auratus)
20) Mantled Guereza (Colobus Guereza)
21) Red-Tailed Guenon (Cercopithecus Ascanius)
22) Lar Gibbon (Hylobates Lar)
23) Mueller's Bornean Gibbon (Hylobates Muelleri)
24) Siamang (Symphalangus Syndactylus)
25) Black-and-White-Ruffed Lemur (Varecia Variegata)
Isle of Wight Zoo - August 2017:
26) Black Lemur (Eulemur Macaco)
27) Mongoose Lemur (Eulemur Mongoz)
28) Black-Capped Capuchin (Sapajus Apella)
Monkey World, Dorset - August 2017
29) Geoffroy's Marmoset (Callithrix Geoffroyi)
30) Patas Monkey (Erythrocebus Patas)
31) Stump-Tailed Macaque (Macaca Arctoides)
32) Golden-Cheeked Gibbon (Nomascus Gabriellae)
33) Bornean Orangutan (Pongo Pygmaeus)
34) Sumatran Orangutan (Pongo Abelii)
35) Common Chimpanzee (Pan Troglodytes)
Pretty pleased with that so far!
Also, if we're noting hybrids then the Spider Monkeys at the Isle of Wight Zoo are also hybrids.