Hoya patella is a very popular species native to
the cloud misted mountains of New Guinea.
World's biggest hoyas and eriostemmas come from the
island of New Guinea.
The photo shows Hoya cf. gigas NS05-195
with 11 cm
big flowers, which I encountered in 2005.
had apparently not been re-collected for nearly 100
years. I saw this one (NS08-030) on a fallen tree in Morobe
Province, which may be H. stenophylla which has linear,
thin leaves on climbing vines with big flowers.
Island of New Guinea
is one of Earth's most biologically rich places. A 5000
metres tall mountain range runs along the entire island,
creating a rugged terrain with a great number of
isolated micro-climatic zones. There are many species
with specific habitat requirements created over the time
in those isolated zones. Those species are most unique
for this island.
popular name for the island New Guinea's huge tracts of
beautiful ancient forests (= primary forests) also
possessing an unique fauna like bird of paradise,
cassowaries, tree kangaroos and many unique
Guinea has a great deal of all known species of
Hoya and its sister genera eg. Dischidia. The right part of island, the country of
Papua New Guinea, has presently about 70
species of Hoya. Some 90% of these have never
been found outside the island. Yet, only a few botanists
have covered a small fraction in
PNG, of which most
occured 100 years ago!
If you see 200
specimens of these sister genera during a trek in the forest, usually
only one of the specimens is in flower. Remaining 199 have
been neglected by the few botanists without any record.
Tribal disputes and cannibalism have scared biologists
off for a long time, however the cannibalism is no
inaccessible landscapes of PNG most likely still possess a
good number of unknown species.
is the last frontier and has the most unique species.
The virgin forests in
the entire distribution range of these genera (India and
Southeast Asia to Samoan islands) have declined
dramatically lately, causing a loss of more than 50% of
natural habitat for all these three genera.
Only a few
species of Hoya appear to be able to re-colonize
within a decade or two, suggesting the most species
in Hoya to be vulnerable.
There is no scientific data yet on this, and the reasons are
still relatively unknown.
Therefore there is a great need for a survey dealing
with the vulnerability, climate requirements, population sizes, distribution
area, and collecting living
material for ex situ conservation. This survey
would reveal new species, and DNA would be accessible
for further studies within these genera, and shed a
light on the reasons of their vulnerability.
is specially important for PNG which is one the least
explored countries, and in PNG most hoyas still
exist, whereas in Southeast Asia you can only study
small fractions of the flora that once existed.
The new findings are expected to be unique for PNG, as
there are many species from New Guinea with
morphological features not seen elsewhere (e.g. Hoya archboldiana,
H. gigas, H.
hypolasia, H. inflata, H. lauterbachii, H. megalaster,
H. microphylla, H. onychoides). Most of them have
exceptionally huge flowers and very ornamental.
Actually, all but about three species with flowers
exceeding 5 cm (2 inches) are from New Guinea. Why has
this island got so huge flowers?
Join us by supporting this survey of PNG's unique