No, a walrus is not closely related to manatees.
A bull manatee is just another word for a male manatee.
There are 3 species of manatee. There is the West Indian manatee, the Amazonian manatee, and the Florida manatee.
Amazon Manatee (Trichechus inunguis) West Indian Manatee (Trichechus manatus) African Manatee (Trichechus senegalensis)
Yes. The West Indian manatee is the proper name of the Florida manataee.
An adult male manatee is sometimes called a bull.
Bulls
The scientific name of seacow is Trichechus manatus for the West Indian manatee and Trichechus senegalensis for the African manatee.
Manatee Mandrill
The West Indian manatee
MANATEEDomain: EukaryaKingdom: AnimaliaPhylum: ChordataSubphylum: VertebrataClass: MammaliaSubclass: TheriaInfraclass: EutheriaOrder: SireniaFamily: TrichechidaeGenus: TrichechusSpecies: Manatus
There are 4 different known species of manatee, all with slightly different scientific names:The Amazonian Manatee is called the Trichechus inunguisThe West Indian Manatee is called the Trichechus manatusThe African Manatee is called the Trichechus senegalensisThe Dwarf Manatee is called the Trichechus pygmaeus(although it has been questioned whether the Dwarf Manatee is indeed a new species)