A survey of rotifers from a small pond (less than 2 ha in area and 3 m deep
), located at Kilometer 28 in the federal highway Ixtlahuaca-Jilotepec (19
degrees 49' 13 " N, 99 degrees 42' 22 " W) at an altitude of 2503 m above s
ea level, resulted in a total of 78 species. From these, 20 are new records
for Mexico. This study confirms the presence of some of the rotifer specie
s listed only in earlier studies. Comments on some species are made from a
zoogeographical point of view.