As I see it, the visual difference:
- neospongoides in this thread are dendronephthya-like: thin skinned, fine sclerites at the distance on the body. But without spicules at the tentacles, polyps are larger, and are star-like (fully opened).
Comparing to what I know as lemnailia:
Lemnalia has:
- V-shaped polyps, never opened so far to become almost flat,
- more branching between stem and polyps, especially the white one,
- much more larger robust sclerites, creating a "bark", absent for balloon-like, fine skinned Kenya tree, dendronephthya and neospongoides in the thread.
- both require light, more, than white xenia and green candycane (don't ask me, how do I know

).
All, together with general coral shape, gives distinct appearance, unlikely be mistaken for anything else. See for yourself:
Dendronephthya (for a fine appearance, I don't have neospongoides):
mostly trunk, not branches:
Purple lemnalia: in previous post and close-up of the "bark":
White lemnalia, even more coarse:
and has hard sheaths for a polyps, lacking for the purple lemnalia:
Kenya tree (in previous post) has something in common:
balloon like, no spicules at all, the same vertical striping and fluffy polyps. Very hardy, no need in high feeding, less light requirements, than lemnalias, IMHE.
GARF has page about neospongoides, don't have links at hand.
Anybody else?