Hey Pat, your fern looks like Sphenomeris chinensis, a common fern in much of east Asia and Polynesia. Check out the link on plants of Hawaii.

It is an easy grower and can even endure quite a bit of frost.

PF

Here is a link that might be useful: Sphenomeris in Hawaii

Pat, I know exactly what you mean about this fern feeling like an Asplenium or even a Diellia, as the two genera are closely related and not always even accorded separate status. But what an astonishing find if this really turns out to be a Diellia! Only half a dozen species to choose from...and most of those unrecorded in the lifetime of anybody likely to be reading this! But it CAN'T be the one Pat suspects - the allegedly extinct D.leucostegeoides - if only on the grounds that it is (was?) a one-pinnate fern whereas the one in the photo is clearly multi-divided.

I can't locate an obvious Asplenium candidate for this one. So, if there are any grounds for supposing this to be one of the long-lost Hawaiian Diellia - not to mention the fact that it's turned up on the wrong island - then D.mannii it would have to be. It's the only species in the genus that's not got that classic one-pinnate 'Nephrolepis' look.

It just feels so far-fetched and so unlikely that it's hard to claim it as Diellia - there must be another explanation. Surely...?

Plantfreak's call - Sphenomeris - would be a logical one and far more credible than a fantastical sighting of the now non-existent Diellia. S.chinensis would be everywhere on the islands, that's for sure.

Bingo ! Yes Sphenomeris chinensis. What threw me was the distinctly scarlet colored stipe, and Palmer discribes in his book on Hawaiian ferns as having straw colored stipes. The sori and indusia are, and general structure - at least when young, are similar to spleenworts and Diellia. Hard to understand why I never noticed what is considered a common fern there. Apparently it is not in cultivation on the mailand. Of course I didn't think Angiopteris was an issue in the islands until I went into Manoa valley. Thanks much for your help.

Pat, one give away is that Sphenomeris sori are borne terminally on the pinnae, unlike Asplenium (see link). Also, S. chinensis can be very colorful in cooler weather especially if the plants are in sun. Here in summer the fronds typically are green colored, but come fall they can turn a lovely bronzy purple throughout.

Here is a link that might be useful: {{gwi:616104}}

Many thanks plant freak. Great shot of the sori. Is this species possible to grow at home from spore?