Complex sentence: The Marco Polo sheep "Ovis ammon polii" was first described by Indian zoologist Edward Blyth in 1841, while another subspecies of "Ovis ammon", the Siberian or Altai argali, was left as the nominal subspecies "Ovis ammon ammon".
Split into simpler sentences: The Marco Polo sheep "Ovis ammon polii" was first described by Indian zoologist Edward Blyth in 1841. Another subspecies of "Ovis ammon", the Siberian or Altai argali, is known as the nominal subspecies "Ovis ammon ammon".