Doryopteris consists of mostly small to medium-size ferns. They usually are terrestrial, or grow on rocks.
D. ludens is one of the larger species. The plant above is in a 12" or 14" pot. Note the broad sterile fronds with the spidery fertile fronds above. This was extremely rare until just a couple of years ago, and most growers did not do well with it.. It is now available at more reasonable prices, and some growers are reporting success. McKee Botanical Garden, in Vero Beach, Florida, even has one thriving in the ground.
Give this plant lots of water, coupled with perfect drainage. The addition of lime seems beneficial.