Today’s short post is all about duality. The number two can up for a few plants we saw on today’s hike. Well duality and one pretty native vine.
On O’ahu, there are 2 endemic species of Lama, Diospyros sandwicensis and D. hillebrandii. D. sandwicensis can be found from dry to wet environments, while D. hillebrandii is mainly found in mesic forest. Where their ranges do overlap, the easiest way to tell the difference is by the leaves. Here’s D. sandwicensis:
And here’s D. hillebrandii:
The venation is much more prominent on Diospyros hillebrandii. There are other differences with leaf size and shape, but this is probably the best way to make a positive id.
Another plant we saw today is one that is very rare in the Ko’olaus: Scaevola gaudichaudii. The name is very easily confused with another naupaka, the similarly named Scaevola gaudichaudiana. From what I can tell the suffix -ii is the personal possessive in latin. The suffix -iana denotes “in honor of”. Either way both plants are named after Charles Gaudichaud-Beaupre, the French botanist who made some of the earliest scientific surveys of the plants in Hawai’i. Here’s the picture:
Scaevola gaudichaudii is a very different plant from S. gaudichaudiana, having these mustard colored flowers, as opposed to the white flowers of S. gaudichaudiana.
The final plant from today’s hike is also another plant that is rare in the Ko’olaus. Awikiwiki (Canavalia galeata) is a native vine in the pea family. The patch that we came across were in flower as well.
Quite the showy infloresence. The flowers are still very popular in lei-making. Don’t ask me to try though; I’d rather see them set seedpods. Plus my lei-making skills are terrible.
Another hike completed, another encounter with uncommon native plants. Whether it’s 2 closely related plants separated by subtle variations, or plants with similar sounding names, or a pretty vine, it is always great to come across these jewels of biodiversity.
Studia Mirabilium 
Thanks for the calibration. Nice shots.
Thanks. The funny thing is that we actually saw a bunch of S. gaudichaudiana on the hike, I just forgot to take pictures of them. Live and learn.
By the way, do you guys know if Scaevola gaudichaudii is common on Maui?
Yeah, the “common” stuff often gets forgotten, like when no one had collected wiliwili seeds for seed storage before the beetle and then the wasp came to town.
Scaevola gaudichaudii is pretty darn rare, and perhaps gone by now, on E. Maui, where we came across a small goat bitten patch in aa lava above La Perouse Bay. It is more common / still present on W. Maui., where it can be found on the leeward ridges.
Here’s some S. gaudichaudii chatter from the “South Slope Report” of 1986.
STATUS OF NATIVE FLOWERING PLANT SPECIES ON
THE SOUTH SLOPE OF HALEAKALA, EAST MAUl, HAWAII
Scaevola gaudichaudi H. & A. 1832 (E:H.I.) Naupaka
This distinctive yellow-flowered Scaevola of lower leeward
forest areas was once known from all major Hawaiian islands,
but has been greatly depleted. Scaevola gaudichaudi can still
be found in small numbers on Oahu and somewhat more abundantly
on northwestern Kauai. Hobdy reports it to be locally common
on West Maui. Forbes collected this species on the south slope
of Haleakala, previously the only collection from East Maui, at
“Kealii forest” (#2121M-3/28/20) with this note: “Small herb,
3 feet. Flowers yellow, fruits purple. Leaves thick with an
ivory felt. Only one seen.” ~. gaudichaudi was seen and
collected during this survey in November 1982. Nineteen
individuals, many flowering and fruiting, were found at 750 ft
below the road at Kepuni Gulch. This is the only known
population of this species on East Maui.
While looking up specimens at Smithsonian for S. gaudichaudii, we think we are the only people to have seen / documented the La Perouse population on E. Maui, we came across this apparent Scaevola gaudichaudii X S. gaudichaudiana hybrid record found on Oahu.
Scaevola gaudichaudii X S. gaudichaudiana
Collected by: Wagner, W.L.; Lau, J.; Ikawa, M. No. 5611
Collection Date: 21 Jul 1985
Hawaiian Islands, Oahu, Wai’anae Dist, Wai’anae Mts, open exposed ridge just N of upper end of Kaluakauilai Gulch.. Alt. 518 m.
Our shots of S. gaudichaudii.
http://www.hear.org/starr/images/species/?q=scaevola+gaudichaudii&o=plants&s=date
Would this happen to be Kūlepeamoa ridge hike?
Yes it is