Yes, mailinatar.com can receive emails.
No, mailinatar.com is a throwaway domain and should be blocked.
You can use MailCheck's free API to automatically block throwaway emails. Read our documentation to get started. No registration required.
A record
178.128.223.21
MX records
mx00.1and1.com
74.208.5.3
mx01.1and1.com
74.208.5.21