Rhipsalis paradoxa ssp. septentrionalis, chainlink cactus. This plant will trail and does best in a hanging planter once it gets established. It will cling to things as it is an epiphytic cactus. Allow to dry between waterings. Warm sunny window inside. Native to parts of Brazil.
 
** Prices and pots size will vary to photos. These are available at the greenhouse if you visit.