Twelve teams are to contest the men's tournament and four will compete in the women's competition.
PNG, Fiji, Samoa, the Cook Islands and a Tongan invitational XIII are the Pacific sides joining the traditional league powerhouses of Australia, New Zealand and England.
Leeds Rhinos second rower Rhyse Martin said it was an honour to be chosen to lead the Kumuls at the World Cup.
"It was a great feeling when coach told me but the feeling I got...when the boys were really excited for me gave me chills and I am really excited to play for the Kumuls," Martin said.
