It can be anything! An apex, subdomain, or even a URL.

Results formail.ialmas.com

Logged At	Not Before	Not After	Common Name	Matching Identities	Issuer Name
2018-04-18T21:54:54.018	2018-04-10T00:00:00	2018-07-09T23:59:59	mail.ialmas.com	mail.ialmas.com	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"
2018-04-16T14:49:04.265	2018-04-16T00:00:00	2018-07-15T23:59:59	mail.ialmas.com	mail.ialmas.com	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"
2018-04-16T14:48:35.055	2018-04-16T00:00:00	2018-07-15T23:59:59	mail.ialmas.com	mail.ialmas.com	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"
2018-04-10T18:45:27.119	2018-04-10T00:00:00	2018-07-09T23:59:59	mail.ialmas.com	mail.ialmas.com	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"
2018-02-25T20:25:41.292	2018-02-01T10:45:03	2020-02-01T10:45:03	*.ialmas.com	*.ialmas.com	C=US, ST=Arizona, L=Scottsdale, O="GoDaddy.com, Inc.", OU=http://certs.godaddy.com/repository/, CN=Go Daddy Secure Certificate Authority - G2