What types of sloths exist?

“There are two types of sloths the two-toed sloth (the Megalonychidae) and the three-toed sloth (the Bradypodidae).  The three-toed sloth has three toes on the front feet and five toes on their hind feet. The two-toed sloth is larger than the three-toed sloth. Sloths phalanges “toes” are said to be like hooked claws in appearance. These curved phalanges are adapted for the sloth’s gripping function as they spend their lives hanging upside down from branches. The third and fourth digits on the hand are highly specialised (arboreal specialisation) for this purpose as the proximal phalanges are short and bent with longer terminal phalanges.  Due to the arboreal specialisation of the terminal phalanges sloths are unable to walk on the ground and have to drag their body along with their claws.  Sloths hand morphology is highly diverse and remarkable. The two-tone sloth (the Megalonychidae) hand only consists of the 2nd and 3rd digits. On the three-toed sloth (the Bradypodidae) hand it only consists of digits 2-4. Sloths palms extend to the interphalangeal joints these joints are formed between the phalanges and add to animal’s stability and strength. In sloths fusion of the phalanges can be seen in the thumb and the two phalanges at the base of the third digit. There are interesting features in the carpals and metacarpals of sloths. They have a vestigial second and fifth metacarpal which then extends to the distal interphalangeal joints as well as fusion of the carpals and metacarpals. During quadrupedal suspensory locomotion, a spatiotemporal gait and inter- and intralimb coordination is present.