Melanistic and non-melanistic animals can be littermates. Melanistic leopards are also called black panthers. Ten unrelated melanistic jaguars were either homozygous or heterozygous for this allele. Melanistic as well as leucistic individuals have been noted. Both leopards and jaguars that are melanistic are known as black panthers. Both albino and melanistic individuals have also been reported. The serval also has melanistic forms in certain areas of East Africa. South of the Isthmus, only melanistic leopards were present. Melanistic cheetahs are rare and have been seen in Zambia and Zimbabwe. One subspecies is melanistic (almost all black). Unlike gray wolves, eastern wolves rarely produce melanistic individuals. A few melanistic bobcats have been sighted and captured in Florida. Individuals with abnormally grey, melanistic plumages have been recorded. There are no authenticated cases of truly melanistic cougars. Approximately nine percent of melanistic eastern gray squirrels are believed to be jet black.