Thursday, February 7, 2013

Papua New Guinea 5. To the Frieda River

From our base along the Frieda River, forest-covered hills beckoned.
I was privileged in 1978 to be able to visit a part of New Guinea virtually untouched by humans.  The Frieda River is a tributary of the Sepik River nestled against the foothills of the central range of mountains.  In recent history at least, there have not even been villages or farms here, just the occasional hunting party.  This provided an extraordinary opportunity to see undisturbed forest with a great variety of plant and animal life.  I was not equipped to photograph birds, but the numbers of hornbills, cockatoos and other natives was exhilarating   In terms of plants it was equally spectacular.  The area yielded a number of palm species never seen by science before, and other surprises like epiphytic gingers.
Our hosts' helicopter dropped us off high in the hills.

 We were hosted by a mineral exploration company, and from their base by the river, we had helicopter service to a landing pad high up in the hills.  These upper areas are moist and mossy, what I would call a cloud forest.  Each day we were dropped off and walked down via varied routes, collecting plants as we went.  I kind of hoped that they wouldn't find anything in the pristine area, and a recent viewing on Google Earth revealed a few scattered mines in the area, but much of the forest intact.
From the air, we saw spectacular tall Livistona palms.

On the ground, the large Livistonas
eluded us.  We saw only juveniles
like this.
One of our first observations from the helicopter was of a spectacular Livistona palm poking up here and there through the forest canopy.  For several days, we looked for the palm as we descended through the forest, but found only a few juvenile individuals.  To this day, I do not know what species it is, or if perhaps it's a new species.  This was the "big one" that got away!

The inflorescence of Orania
with branches covered
with soft, orangish scales, is held by
Yakas, who worked for the Division of
Botany in Lae for many years.
Orania parva has a very small

But there was plenty to see otherwise.  A  species of Orania, quite different from the one we had seen earlier at Amanab in the Sepik River valley, showed up along one of our descents.  It proved to be a specimen of the widespread O. lauterbachiana, or possibly a new species closely related to it.  In another valley, we found a different Orania, which proved to be a new species. I later named it Orania parva, for its rather small dimensions.
An unnamed Licuala held by Brad Young
Licualas have fan-shaped leaves with
leaflets spreading in a nearly perfect circle, and
red fruits.  

Hydriastele aprica, a new species found on limestone ridges.
The fruits of Hydriastele aprica, a
species new to science when we found
it in 1978.
Even more exciting was the discovery of a new species of Hydriastele, though we called it Nengella in those days.  This dainty palm was growing on a limestone ridge in the forest, and differs from similar species in its purplish rather than bright pink flowers.  My graduate student, Brad Young, who accompanied me on this trip later did his Master's dissertation on this section of the genus and named the new species Nengella aprica.  Later, we combined Nengella with Gronophyllum, and several decades later, Gronophyllum was combined, along with Gulubia into the large genus  Hydriastele.

Just downslope from the Hydriastele, we found a species of Nepenthes clambering over the limestone boulder.  This was a delightful surprise.  Limestone areas always seem to have unique species growing on them.  Another surprise was to find several members of the ginger family growing as epiphytes on low branches in the upper cloud forest.
The male flowers of Hydriastele aprica are
whitish with purple tips.  They will open first,
followed by the tiny female flowers hidden
beneath them. 

A species of Nepenthes climbs over the limestone boulders.

A dainty Riedelia in the ginger family (Zingiberaceae) grows as an epiphyte
 in the cloud forest.

Mucuna novoguineensis is a spectacular vine in the legume family (Fabaceae).

Forrestia mollisma is in the Commelinaceae.
A tiny orchid blooms in the cloud forest.
Hydriastele longispatha had not been seen since being collected by Leonard Brass
in the 1930's. Growing just down the limestone slope from the Hydriastele was a population of pitcher plants, Nepenthes.  

One day, we stumbled onto a population of Hydriastele loongispatha (originally described as Gulubia longispatha) perched on a high mountain ridge.  As we know it now, Hydriastele is one of the largest, most diverse, and widespread genera of palms in New Guinea.

The Frieda River Valley, as I remember it from 1978.