Robtex

Up: 64.16.64.0/19
Can't show all results, try to descend to a more specific CIDR
Down left: 64.16.80.0/21
Down right: 64.16.88.0/21
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
64.16.80.16	PTR	unused.spark-networks.com
64.16.80.47	A	static.matchnet.com
64.16.80.47	A	static.spark.net
64.16.80.47	A	static.spark-networks.com
64.16.80.48	PTR	www.americansingles.com
64.16.80.48	A	www.americansingles-usa.com
64.16.80.48	A	ridehelp.org
64.16.80.49	PTR	www.spark-networks.com
64.16.80.50	PTR	www.jdate.com
64.16.80.51	PTR	unused.spark-networks.com
64.16.80.64	A	pixel.spark-networks.com
64.16.80.65	A+PTR	survey.spark-networks.com
64.16.80.65	A	stuandlew.com
64.16.80.70	A	committedsites.com
64.16.80.80	PTR	unused.spark-networks.com
64.16.80.81	PTR	unused.spark-networks.com
64.16.80.81	A	www.believe.com
64.16.80.81	A	believe.com
64.16.80.91	A	connect.americansingles.com
64.16.80.97	A+PTR	connect.jdate.fr
64.16.80.120	A	sparkws.spark-networks.com
64.16.80.161	A	seo.spark-networks.com
64.16.80.161	A	search.date.ca
64.16.80.171	A	m.jdate.com
64.16.80.192	PTR	www.hurrydate.com
64.16.80.192	A	hurrytalk.com
64.16.80.192	A	speeddatingisfun.com
64.16.80.193	PTR	unused.spark-networks.com
64.16.80.193	A	hurrydate.org
64.16.80.195	PTR	unused.spark-networks.com
64.16.80.195	A	hurryadate.com
64.16.80.224	PTR	unused.spark-networks.com
64.16.80.224	A	www.faith.com
64.16.80.224	A	faith.com
64.16.80.225	PTR	unused.spark-networks.com
64.16.80.225	A	gospelmediagroup.com
64.16.80.226	PTR	unused.spark-networks.com
64.16.80.226	A	christiancards.net
64.16.80.227	PTR	unused.spark-networks.com
64.16.81.246	A	matchnet.com
64.16.82.146	PTR	unused.spark-networks.com
64.16.83.51	A+PTR	ns02.spark-networks.com
64.16.83.128	PTR	unused.spark-networks.com
64.16.83.128	A	*.adventistsinglesconnection.com
64.16.83.128	A	adventistsinglesconnection.com
64.16.83.130	PTR	unused.spark-networks.com
64.16.83.131	PTR	unused.spark-networks.com
64.16.83.155	A	beta.christianmingle.com
64.16.83.160	PTR	unused.spark-networks.com
64.16.83.200	A	ns03.spark-networks.com
64.16.83.201	A	ldssingleslive.com
64.16.83.201	A	relasionships.net
64.16.83.201	A	seniorssinglesmeet.com
64.16.83.208	PTR	unused.spark-networks.com
64.16.83.217	A	pixels.spark.net
64.16.84.51	A+PTR	ns01.spark-networks.com
64.16.84.92	A	premium.jdate.co.il
64.16.84.205	A	mx.adventistsinglesconnection.com
64.16.84.205	A	mx.catholicmingle.com
64.16.84.205	A	mail.minglematch.com
64.16.85.33	PTR	unused.spark-networks.com
64.16.85.80	PTR	unused.spark-networks.com
64.16.85.82	PTR	unused.spark-networks.com
64.16.85.86	A	news.hurrydate.com
64.16.85.86	A	mail.hurrytalk.com
64.16.85.86	A	email.hurrydate.com
64.16.85.101	A	lajuniper2-ge-020.matchnet.com
64.16.86.4	PTR	unused.spark-networks.com
64.16.86.34	PTR	unused.spark-networks.com
64.16.86.51	PTR	unused.spark-networks.com
64.16.86.113	PTR	unused.spark-networks.com
64.16.86.177	PTR	unused.spark-networks.com
64.16.86.227	PTR	unused.spark-networks.com
64.16.87.31	A	mx01.spark-networks.com
64.16.87.32	A+PTR	mx02.spark-networks.com
64.16.87.33	A+PTR	mxcorp01.spark-networks.com
64.16.87.34	A+PTR	mxcorp02.spark-networks.com
64.16.87.35	A+PTR	antispam01.spark.net
64.16.87.48	A+PTR	mta1-1.jdate.fr
64.16.87.50	A+PTR	mta1-1.spark.net
64.16.87.51	A+PTR	mta1-1.spark-networks.com
64.16.87.53	A	mta1-1.spark-affiliates.com
64.16.87.64	A+PTR	mta1-2.date.ca
64.16.87.66	A	mta1-2.jdate.co.il
64.16.87.67	PTR	mta1-1.iministries.org
64.16.87.70	A	mta1-2.spark.net
64.16.87.71	A	mta1-2.spark-networks.com
64.16.87.81	A+PTR	mta2-1.americansingles.com
64.16.87.84	A	mta2-1.date.ca
64.16.87.86	A	mta2-1.jdate.co.il
64.16.87.87	A	mta2-1.jdate.com
64.16.87.101	A	mta2-2.americansingles.com
64.16.87.104	A	mta2-2.date.ca
64.16.87.106	A	mta2-2.jdate.co.il
64.16.87.110	A	mta2-2.spark.net
64.16.87.121	A	mta3-1.jdate.com
64.16.87.121	A	mail-nc-1-1.americansingles.com
64.16.87.122	A	mta3-1.jdate.fr
64.16.87.124	A	mail-nc-1-1.date.ca
64.16.87.133	A	mta3-1.spark.com
64.16.87.141	A	mail-nc-2-1.americansingles.com
64.16.87.144	A+PTR	mail-nc-2-1.date.ca
64.16.87.146	A+PTR	mail-nc-2-1.jdate.co.il
64.16.87.161	A+PTR	mta1-1.adventistsinglesconnection.com
64.16.87.161	A	mail-tcoi-1-1.americansingles.com
64.16.87.163	PTR	mta1-1.bbwpersonalsplus.com
64.16.87.163	A	mail-tcoi-1-1.cupid.co.il
64.16.87.164	A	mail-tcoi-1-1.date.ca
64.16.87.181	A	mail-tcoi-2-1.americansingles.com
64.16.87.184	A	mail-tcoi-2-1.date.ca
64.16.87.184	A	mta1-1.usasinglesconnection.com
64.16.87.186	A	mail-tcoi-2-1.jdate.co.il
64.16.87.201	A	mta2-1.adventistsinglesconnection.com
64.16.87.201	A	mail-soi-1-1.americansingles.com
64.16.87.204	A	mta2-1.blacksingles.com
64.16.87.204	A	mail-soi-1-1.date.ca
64.16.87.208	A	mta2-1.christianmingle.com
64.16.87.221	A	mail-soi-2-1.americansingles.com
64.16.87.224	A+PTR	mta2-1.usasinglesconnection.com
64.16.87.224	A	mail-soi-2-1.date.ca
64.16.87.226	PTR	unused.minglematch.com
64.16.87.226	A	mail-soi-2-1.jdate.co.il
64.16.87.241	PTR	unused.minglematch.com
64.16.87.241	A	mail-soi-1-2.americansingles.com
64.16.87.247	A	mail-soi-2-2.americansingles.com
64.16.89.49	PTR	unused.spark-networks.com
64.16.89.145	PTR	unused.spark-networks.com
64.16.94.18	PTR	unused.spark-networks.com
64.16.94.33	PTR	unused.spark-networks.com
64.16.94.81	PTR	unused.spark-networks.com
64.16.94.96	PTR	unused.spark-networks.com
64.16.94.226	PTR	unused.spark-networks.com
64.16.95.112	PTR	unused.spark-networks.com
64.16.95.161	PTR	unused.spark-networks.com
64.16.95.210	PTR	unused.spark-networks.com
64.16.95.241	PTR	unused.spark-networks.com