MX records for WebMasterWorld.com

[sdani]

I had to switch my e-mail host yesterday in an emergency situation, so I was looking for some of the sites that I visit often to see where do they host their emails.

I found out that webmasterworld.com's MX records were missing. I noticed the same for searchengineworld.com. I thought may be its a temporary issue, but I was curious again this morning to check this out.

I still don't see MX records for WebMasterWorld. Is there a way to hide them on DNS or is it an error?

[dnsstuff.com...]

[sdani]

may be andreasfriedrich's response here answers this question.
[webmasterworld.com...]

This is something new I learnt today that an email can be delivered without MX record.