These scammers, presumably Nigerian, advertise puppies for sale, in this case Maltese on legitimate websites such as PuppyFind.com. The original contact, "Barbara Serrat Bates" claims to be a 32 yr old, pregnant, Washington state resident who is a Travelling Nurse working in Miami. They post cute pictures of puppies for sale at low market prices with low shipping costs. They claim to send all kinds of expensive toys with the animal.
They use burner cell phones, one of which was 941-348-2362 that quickly go unanswered as the scam unfolds. They provide "Dr. Jeffery" as a veterinary reference. His English is barely intelligible. They insist on having the funds sent via Western Union (the first clue that this is fraud).
Don't assume dirt bags like this cant be caught. Report them to anyone and everyone everywhere.