GREEN PYTHONS
GENUS CHONDROPYTHON MEYER, 1874
The taxonomy
of Green Pythons has been recently revised.
There are now two
recognized species and two more recognized subspecies.
These
are:
Chondropython
viridis (Schlegel 1872), known as the Aru Islands Green Python or
the Southern New Guinea Green Python
Chondropython
viridis shireenae Hoser 2003, known as the Australian
Green Python.
Chondropython
viridis adelynhoserae Hoser 2009 known as the Normanby
Island Green Python.
Chondropython azureus Meyer
1875, known as the Northern New Guinea Green Python, including the Biak Green
Python and others.
Some
authors prefer to place the Green Pythons in the genus Morelia, thereby making
it some sort of “greater Morelia”.
Then
the breakdown would be:
Morelia
viridis (Schlegel 1872), known as the Aru Islands Green Python or
the Southern New Guinea Green Python
Morelia
viridis shireenae Hoser 2003, known as the Australian
Green Python.
Morelia
viridis adelynhoserae Hoser 2009 known as the Normanby
Island Green Python.
Morelia azureus Meyer
1875, known as the Northern New Guinea Green Python, including the Biak Green
Python and others.
A
more detailed summary about the taxonomy of Green Pythons is taken from a
recent paper, the relevant part is reprinted unedited below
CHONDROPYTHON
MEYER 1874
Designation
of so-called “Green Pythons” in the genus Chondropython
has been the normal situation among taxonomists for most of the past 100
years. Having said this, in recent
times a number of taxonomists lump the Green Pythons in the genus Morelia, noting the obvious affinities
between the two groups.
Hobbyists
still call the snakes “Chondro’s” regardless of what scientific name they use.
Allowing
for the latter placement of these snakes in the supergenus “Morelia”, these snakes remain outside
the core Morelia group of “Carpet
Pythons”, with the Australiasis snakes
(so-called Scrub Pythons) also forming a different group.
If
one doesn’t accept the obvious splits to include the genera Australiasis, Lenhoserus and Chondropython,
then all preceding names are available at the subgenus level.
For
the purposes of this paper and following on from Hoser 2000b, Chondropython is treated here as a full
genus.
Rawlings
and Donellan (2003) in their Phylogeographic Analysis of the Green Python,
yielded results in accordance with similar studies for other snake genera with
similar cross New Guinea distributions, including Acanthophis (Hoser 1998), Leiopython
(Hoser 2000) and Australiasis (Harvey
et. al. 2000).
While
Hoser 1998 and Hoser 2000b did not relate the findings with geological evidence
in terms of seeking explanations for results, other authors including Harvey
et. al. (2000) have.
That
is that as a result of the formation and uplifting of the central New Guinea
range commencing about 5 million years before present, species were split into
allopatric groups which in turn speciated, giving the present day results.
Hence
the barriers affecting one species seems to have similarly affected others,
giving a near mirror image distribution patterns for the various python genera
(as diagnosed by Hoser 2000b) and also perhaps elapid groups as well.
That
Rawlings and Donellan found evidence to support two species of Green Python was
not a surprise and had been anticipated by hobbyist keepers for decades.
They
wrote:
“The
pattern of relationships found for mitochondrial and nuclear genes suggests the
presence of two species of M. viridis,
one present north of the central cordillera and the other present in Southern
New Guinea and Australia.”
Their
mtDNA evidence in terms of the outlier Australian population concurred with
Hoser 2000b and McDowell 1975 in that while it had clear affinities to the
southern New Guinea snakes, they were derived from them in relatively recent
geological time and by a migration south from the main population.
Hobbyist
keepers in Europe and the USA were well aware of the different pattern morphs
from different locations over many years, including differences between those
from north and south of the main dividing range.
While
Rawlings and Donellan 2003 didn’t concern themselves with nomenclature of the
regional forms of Green Python, all taxa have been named at the species
level. This contradicts Rawlings et.
al. 2008, p. 604, who state the northern New Guinea taxon is “unnamed”, when in
fact it was named in 1875 by Meyer.
Furthermore one of two obvious subspecies, the Australian Green Python (Chondropython viridis shireenae) Hoser
2003 has also been named.
A
second highly distinct form of Green Python, hitherto unnamed and from Normanby
Island, Milne Bay Province, PNG, is formally described for the first time here
as the subspecies Chondropython viridis
adelynhoserae subsp. nov.
That
these snakes differ from other Chondropython
has been speculated for some time.
However until recently I had not seen any specimens in life or good
quality photos of specimens in life.
DNA evidence as provided by Rawlings and Donnellan 2003 also supports
the hypothesis that these snakes differ from other Chondropython and are reproductively isolated from them and have
been for some time.
For
the record, Chondropython pulcher
Sauvage 1878, is a synonym of C. azureus Meyer
1875 being derived from the same general region as C. azureus.
Chondropython viridis Adelynhoserae subsp.
nov.
Holotype:
A specimen in the Australian Museum R129716, from Normanby Island, Milne Bay,
Papua New Guinea.
Diagnosis: This
is the form of Green Python restricted to Normanby Island, Milne Bay Province,
PNG.
It
is separated from all other Chondropython
in New Guinea and Australia by it’s adult dorsal pattern of (smallish) white
blotches that in the main do not cover the spinal ridge, as seen in all other
Australian and other PNG Chondropython.
Sometimes
Chondropython from elsewhere will
have similar blotches, but invariably, these snakes either also have a
mid-dorsal line or dots (not seen in adelynhoserae),
or the blotches run well over the spinal (mid dorsal) mid-line.
MtDNA
for the holotype was examined by Rawlings and Donellan 2003 and compared with
other Chondropython yielding traits
broadly in line with C. viridis viridis
(but a three per cent sequence divergence) (see p. 41 their paper). Having said that, it also shared five
nucleotide substitutions that would otherwise be synapomorphies of the northern
lineage, one of which is an indel.
This
result in terms of mtDNA and base pair analysis, as published by Rawlings and
Donellan 2003, forms an additional and/or alternative diagnostic means of
identifying and separating C. v.
adelynhoserae subsp. nov. from other Chondropython.
In
other words, the taxon C. v.
adelynhoserae subsp. nov. can be separated from other C. viridis by the degree of base pair separation/divergence of
mtDNA and/or nuclear DNA as detailed by Rawlings and Donellan 2003.
This
is the only Chondropython taxon found
on Normanby Island, Milne Bay Province, PNG and is allopatric to all other C. viridis or C. azureus.
Etymology:
Named after the elder daughter of this author, Adelyn (pronounced: Adder-lyn)
Hoser, in honor of her valuable education work at educational reptile
demonstrations and the like, including from the age of five safely handling
venomoid versions of the world’s five deadliest snake genera, namely Parademansia, Oxyuranus, Pseudonaja, Notechis and Acanthophis and most importantly after five years of doing so,
never having had a single bite! This emphatically proves that the best way to
avoid snakebites is to be nice to them.
CHONDROPYTHON SUMARY
Based
on what is now believed to be allopatric distribution and factors outlined elsewhere,
the named taxa of Green Python are now as follows:
Chondropython
viridis (Schlegel 1872), southern New Guinea generally and offshore
Islands.
Chondropython
viridis shireenae Hoser 2003, Australia only.
Chondropython
viridis adelynhoserae subsp. nov. (this paper), Normanby
Island, New Guinea.
Chondropython
azureus Meyer 1875, New Guinea north of the central range, including
offshore islands.
Maxwell
(2005), gave detailed information about local “races” of Chondropython, including from islands. However noting the extreme phenotypic variation of the genus and
the non-sampling of intermediate populations (when available), and the added
variables of local adaptations to altitude and so on resulting in localized
colour variants and the like, there is no evidence that any of the forms
identified in the book warrant recognition beyond the taxa (to subspecies
level) identified in this paper based on available evidence, most notably that
of Rawlings and Donnellan 2003.
Notwithstanding
this, the book remains mandatory reading for those with an interest in the
genus.
The above is from the
paper:
To download the paper
in full, click on the text above and follow the relevant links.
Webpage keywords include:Green Python Chondropython viridis, Australia, Australian, Chondropython viridis shireenae, Chondropython azureus is from Northern New Guinea, species and subspecies, Chondropython adelynhoserae is from Normanby Island, PNG, Meyer, Hoser, 2009, Hoser 2003, Hoser 2000, python taxonomy, Green python from Australia, Australian green python, Iron Range, Queensland has Green Pythons, Merauke Green Python is viridis, Green Tree Python, Chondropython nominate form is from southern New Guinea and nearby Islands, Green Tree Python, lives in trees and other habitats, a tree dweller most of the time, ambush predator
