Simplify the following text for a Grade 6 native English-speaking person.
Original: One clade formed by Bacillus anthracis , Bacillus cereus , Bacillus mycoides , Bacillus pseudomycoides , Bacillus thuringiensis and Bacillus weihenstephanensis under current classification standards should be a single species ( within 97 % 16S identity ) , but due to medical reasons they are considered separate species , an issue also present for four species of Shigella and Escherichia coli .
Simplified: Bacillus is also the name of some species in the Bacillus group .