There was one, apparently badly damaged, specimen collected back in 1961. As far as I can tell, they've never been seen since. There have been signs that they may still exist though, so hopefully they are just extra good at hiding. This echidna probably eat worms and insects. Like other Long-beaked Echidna they don't have teeth and can't even bite. They lay eggs, produce milk but don't have nipples, and have an extremely low body temperature. They have electro-receptors in their "beak". As of 2015, there was only one biologist, Muse Opiang, who had done any field work on any of the Long-beaked Echidna! I'm not sure there has been anyone else doing much if any study in the wild since then.
I've taken a bit of creative license here. I wanted to do the face, but very few of the bigger spines would likely have shown in this view, if any, but I still felt I should show them. This is one of the cases where art takes a bit more precedence than accuracy. Well, really I've only seen one picture of the specimen, and it is of it on its back so I haven't seen what they look like in this view. I looked at other long-beaked echidna though, and it has a bit more pokey bits than they are, and I'm ok with that. Honestly, I kind of want to do a few alternative paintings that are less accurate, more just eyes and a hint of the rest of the animal so you can tell what they are. I think it would be fun. Maybe after I've done a year of this I will do something more like that for a week or so.