Complex sentence: The exact number of Pygmy Three-toed Sloths is not completely known, although their population is presumbly low due to its restricted range and it is estimated that there are only around a few hundred alive.
Split into simpler sentences: The exact number of Pygmy Three-toed Sloths is not completely known. Although their population is presumbly low due to its restricted range and it is estimated that there is only around a few hundred alive.