host-157-100-33-237.ecua.net.ec has no MX records.
Question and response
Question
dig host-157-100-33-237.ecua.net.ec. MX
Answer
The response has no answer records.
Authority
ecua.net.ec. 86400 SOA ecua.net.ec. jmiranda.ecua.net.ec. 2016081608 28800 7200 1209600 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0