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How do strepsirrhines differ from haplorrhines in their noses and eyes?

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Illustration comparing the body plans of representative anthropoids, showing a male western lowland gorilla, a male human, a male bonobo, a female Bornean orangutan, and male and female northern white-cheeked gibbons, all labeled and depicted to scale. — primate Representative apes (superfamily Hominoidea).

The suborders Strepsirrhini (lemurs and lorises) and Haplorrhini (tarsiers, monkeys, and apes) exhibit distinct anatomical differences in their noses and eyes:1

Nose: Strepsirrhines possess a moist, bare muzzle—known as a rhinarium—similar to that of a dog. In contrast, haplorrhines have a nose that is covered with downy hair.1
Eyes: Strepsirrhines have a reflective layer behind the retina called the tapetum lucidum, which enhances night vision. Haplorrhines lack this reflective layer and instead possess an area of enhanced vision known as the fovea.1

These differences are consistent across the suborders, regardless of whether specific species are primarily nocturnal or diurnal.1