Final answer:
Primates have distinguishing characteristics such as five fingers, specialized teeth, eye orbit features, and an opposable thumb. Haplorhini primates are divided into two groups: Simiiformes and Tarsiiformes. The Simiiformes group further splits into Platyrrhini and Catarrhini, each having specific traits and characteristics.
Step-by-step explanation:
Distinguishing Characteristics of Primates, Haplorhini, Catarrhini, and Hominoidea
Primates are characterized by features such as five fingers, several types of teeth, certain eye orbit characteristics, and an opposable thumb. Haplorhini primates are divided into two groups: Simiiformes and Tarsiiformes. Simiiformes are further divided into Platyrrhini and Catarrhini. Platyrrhini primates, also known as New World monkeys, are found in Central and South America and have a rounded external nostril shape and prehensile tails. Catarrhini primates, found in Africa and Asia, have narrow downward-facing nostrils. They further divide into Cercopithecoidea and Hominoidea, with Cercopithecoidea having cheek pouch monkeys and leaf-eating monkeys, and Hominoidea including gibbons, chimpanzees, gorillas, orangutans, and humans.