BLUMEA 26(1980)
177-190
A taxonomic revision of Isoetes L.
J.R.
New Guinea
Papua
P.O.
(Isoetaceae)
Croft
Office of Forests,
Lae, P
314,
Box
in Papuasia
Division
of
Botany,
N. G.
Summary
In this revision 4 endemic
of New Guinea.
regions
Croft
are
furnish
described
as new.
Scanning
related
I.
species,
varieties,
two
Croft,
electron
characters,
important diagnostic
possibly
onewith
species,
Isoetes stevensii
micrographs
recognized
and I.
from the
alpine and subalpine
neoguineensis Baker
of the megaspores and
for all
presented
are
are
hopeiCroft,
I.
the
taxa
in
rheophila
var.
microspores,
Papuasia
as
well
which
for the
as
Alston.
philippinensis
Introduction
Isoetes
Isoetes
The
von
Mueller (von
the
neoguineensis
has been
family
but it
first recorded
was
Ferdinand
was
not
Since
the
specimens
monographed
last
(Alston,
account
for
available
recognized
taxa
revision is based
(LAE),
on
C.S.I.R.O.
herbaria of the
and has been
and
Habit. The
and
the
degree
19).
The
Botanic
and
water;
they
single
subalpine
holding
narrower
are
not as
collection
intergradation
to
Papuasia
be
Gardens,
by
inadequate,
Papua
and
field work
with the
unable
and will
aquatic
(K)
both in
ground,
the
more
leaves
the
as
1899).
than
one
within these
number of
This
terms
additional
of the number
The
taxa.
present
and type material from the
and the Arnold Arboretum (A),
four of the five
on
is that of a
Papuasia
positions
further
1959)
ten-fold.
to
by
even
3 of the 5
taxa.
submerged aquatic
taxa.
The leaves
when removed from the
aquatic
rosette
not
easily
(Plate
are
much
break when bent. It is known from a
are
required
to
see
if
there
The compact terrestrial cushion
rosette.
as
turgid
water
support themselves when removed from the
collections
arising
rosette
are
in that the leaves
with both these habit types. The rootstock is imbedded some 7
of the
(Baker,
USED IN SPECIES DELIMITATION
habit in
are
turgid
and
Baron
passing
New Guinea National Herbarium
(CANB),
Kew
tarns, exhibited
their
(Alston,
almost
of variation
habit differs from the
flowing
longer
in
increased
Herbarium Australiense
most common
spreading,
has
account
supplemented
or
it in
(Sadebeck, 1901; Pfeiffer, 1922),
realised that New Guinea had
of Isoetes
study
CHARACTERS
of still alpine
twice since then
was
by
1898
to
until 1899
validly published
the collections of the
Royal
Guinea in
he referred
1945).
material has shown Alston's
of
Island of New
not
name was
until 1945 that it
of Isoetes
species
from the
Mueller, 1898). Although
a
compact cylindrical
cm
is
any
contrasts
below the surface
column,
spreading
BLUMEA
178\19_20
abruptly
at
the surface
-
VOL.
(Plate 21). Again
26.
no.
I.
this habit
1980
type
is
represented
by
collection. No intermediates between the terrestrial cushion and the other
types
Plate
tip
cut
are
single
habit
know.
19 & 20.
off,
a
two
Rootstock of Isoetes habbemensis
x 2/3. (both
from
Croft 56).
Alston. — 19.
lateral
view,
x
½;
20.
seen
from
below,
J.
Plate
21.
Isoetes
Lobes
useful
R. Croft:
of rootstock.
character for
lections
and
habit
hopei Croft,
A
revision
Alston
the
of
3-lobed
the
the leafin
far
to
be of
habit. The
limited extent the
use
schape,
leaves
fall into
and
I.
habbemensis
base
shows
individuals
Ligule.
ligule
no
to
any
While useful
varies
and ±
correlation
be of
too
deltoid.
a
use
of the rootstock
However,
I.
to
subsequent
be
a
col-
and
stevensii,
I.
with the
populations,
leaf,
I.
a
very
hopei has
finer
with
populations
taxa, with the
and
to
describe,
of correlation with the
coarse
narrower
leathery
leaves.
Of the
leaves than I. stevensii. The
other characters
and
varies
with the
and
former
too
to
a
of the
remaining
coarser
shape
of
overlap
structure
leaves. The
I. stevensii with
length
ranges
of that
exception
difficult aspect
habbemensis and
coarser
characters. The
good macroscopic
good degree
with
have
to
lobing
habbemensis,
variable within
separating
species
neoguineensis
appears
very
of the
groups: I.
two
situ).
species.
of I.
179\21
Papuasia
(Plate 19, 20).
show
megaspore. The terrestrial
species
in
texture
in
in
vary between 2 and 5 in
to
rather poor in
are
individuals is
mature
much
too
flowing
usual
most
Malesian
populations
have shown the lobes
state
(Isoetaceae)
considered the
(1959)
neoguineensis
Leaves. The leaves
Isoetes
(ANV 16114. holotype
separating
field studies
of
broader
group I.
of the leaf
much
within
taxonomically.
taxonomically
insignificantly
to
be of
in other
any
use
regions,
in
the
shape
Papuasia, being
and size
in all
cases
of the
small
180
BLUMEA
Velum. The presence and
character in Isoetes. All
shape,
VOL. 26.
-
absence of
or
species
in
Papuasia
instance,
I.
hopei,
1,
no.
velum is
a
lack
1980
very useful
a
diagnostic
velum, emphasising their close
a
relationship.
In
Megaspores.
one
character
significant
correlates
and
the
with
size difference of the megaspore is
The ornamentation of the megaspore is
sculpturing.
character for
determined
separating
the 4
Papuasia,
and
states
significant
being readily
are:
equatorial ridges (Plate 1,2);
wrinkled of relief lower than the trilete
irregularly
a
megaspore
most
species recognized
any reliefother than trilete and
and
habit
far the
by
this character. The four character
solely by
i) psilate, absence of
ii) rugulose, finely
in
taxa
in
differences
ridges
(Plate 4, 6);
iii) evenly reticulate,
than the trilete
open, regular
an
ridges (Plate
iv) unevenly reticulate,
an
that of the trilete
exceeding
The megaspores
discerned with
The
Microspores.
ranges of size
considered
in all
reliefoften
jagged
readily
magnification.
of the
microspores
uneven or
appearing warty (Plate 10, 11,13, 14).
diameter and the ornamentationcan be
x
Papuasia
but that in
species overlap,
species
are
species,
one
all
±
spinulose.
The
I. stevensii, could be
smaller than the others.
significantly
Gametophyte.
and
The-gametophyte
but has yet
characters,
and often
f mm
about
are
reticulum of
regular
open
ridges
hand-lens of 10
a
reticulum of even relief less
honeycomb-like
17);
be
to
its
development
in the
investigated
provide
may
Papuasian
diagnostic
taxa.
ACKNOWLEDGEMENTS
The author wishes
Botany,
not
for
translated the
only
throughout
Graig
to thank the
the
Assistant
descriptions into latin,
and invaluable
study
Director, Papua
to undertake this
granting permission
but who
criticism in
provided
bringing
Marsden and Mr. Robert Chinnock both read the
Geoff
Hope kindly
curators/directors
provided
the
photograph
of the C.S.I.R O.
Herbarium
Gardens Kew and the Arnold Arboretum
electron
scanning
micrographs
of Adelaide
University
on an
of
Isoetes
ETEC Autoscan
in
Mr
in
and
making
and
and
encouragement
form. Mr.
valuable criticism. Dr.
much
discussion.
of the
The
Botanic
Royal
type material available
of the
of
Barker who
publishable
a
herbaria
Marsden
electron
to
provided
situ
the
due to Dr. Bill
polemic
drafts
and
hopei
Craig
scanning
Office of Forests Division
are
continual
manuscript
very kind
were
thanks
the first
Australiense
prepared by
were
New Guinea
Sincerest
study.
loan. The
on
Botany Department,
microscope (see Marsden,
1976).
LITERATURE
—
H.
A.
ALSTON,
1959.
BAKER,
J. G.
COODE,
M
1945. A
1899. in
G. S.
new
Flora
Sci. Soc.
1976a.
1:
II,
62-64, fig.
of British New
Proc. 23:
Vegetation, in
the Australian
of Isoetes from New Guinea.
species
S. STEVENS.
J. E., & P. F.
Guinea
HOPE,
G.
Isoetaceae. Fl. Males.
18
1972.
—
G. S.
Universities'
Guinea.
Notes
1,
25, fig.
Hope,
on
pi.
Kew Bull
1899:
the flora
of two
the
Am.
Arb.
26:
180.
122.
Papuan
mountains.
Papua
New
1—3.
J. A. Peterson & U.
Expedition to
J.
1.
glaciers
Radok eds.
of Irian
Jaya,
Gunung Es
1971
-
—
Results of
1973. A. A. Balkema,
Rotterdam.
.
1976b. The
1
—
C. R
MARSDEN,
Gard.
E.
MERRILL,
MUELLER,
PFEIFFER,
vegetational history
of Mt
Wilhelm, Papua
New Guinea.
J. Ecol. 64: 627
—
661,
fig.
11, pi. 1—2, appendix.
1976
35
1:
D
.
E.
Morphological variation
54, fig.
& L. M.
F. VON.
N
—
1898.
1922.
1—29,
PERRY.
in
map
1940. A
the Annual
Monograph
and taxonomy oflsoetes muelleri
R. Br. J. Adelaide
1.
new
Philippine
Reports
of Isoetaceae.
Isoetes.
of British New
Ann. Miss.
Amer.
Guinea
Bot. Gard.
J. 9:
Fern
18
—
20,
fig.
1897—
1898. p.
149.
9:
232, pi.
12-
76
—
19.
Bot
J.
O.
POSTHUMUS,
Bot.
SADEBECK,
1934. in C. G. G
Buit.
13:
Ill,
1902.
R.
R. Croft:
A
J.
of hoetes (Isoelaceae)
revision
Steenis. The origin of the
van
181
Papuasia
in
Malaysian mountain
flora. Bull.
Jard
169.
in
Isoetaceae,
A.
Engler &
Prantl.
K.
eds.
Die
natiirlichen
Pflanzenfamilien
1,4:
Prantl, Pfl.
1, 4
455-466.
756-779, fig.
ISOETES
Isoetes
PI.
L., Sp.
(1753) 1100;
Gen. PI. ed. 5
Ann.
Pfeiffer,
756-779;
(1901)
(1754) 846; Sadebeck,
Miss. Bot. Gard.
in
Engler &
(1922) 76-232; Alston,
8
Fl.
Males.
Fam.
1
II,
(1959)
62-64.
rootstock,
Leaves
adaxially
which
with
mm
stomata
adaxial basal
an
long (—15
in
solitary,
adnate
an
cavity.
250
spines,
—
containing
and
of the
apex
diameter,
white
sporophylls
to
to
(to
grey
or
microscopic;
development
with 1
—
12
black
of
at
subulate, 1 —2
to
least
potentially
4—11
mm
the
when
young,
Sporangia
so.
long, broadly
sporangium,
attached
300
—
outside
the
to
or
ridges,
Microsporangia
—
45
papillose. Gametophyte
within
prothallus
megaspores
monolete, 20
microspores
scabrous
of the
with warts,
Papuasia).
or
extending
sides
megaspores;
variously sculptured
(outside Papuasia) smooth,
megagametophyte
50
containing
longitudinal
membranous velum absent
a
and
sporangium
4
by
septate, thin-walled, annulus
covering
150,000—1,000,000 microspores;
or
oblong,
flattened
lacking; ligule arising
or
deltoid
or
±
or
broadly expanded,
divided
surfaces,
incompletely
smooth
terete
mucilage-secreting
entirely
tissue.
overlapping
with base
mesophyll
sporangial walls;
or
Megasporangia
2900
long, spinulose
dioecious,
of dead
Roots
corm-like
flattened,
tuft from flattenedapex of rootstock,
both
cavity, elliptic
partially
drying
etc.,
a
sporangial cavity,
All leaves
of
by decay
downwards from the
one or
Papuasia),
adaxial basal
Papuasia)
sporangial
in
submerged aquatic.
or
2 —5-lobed,
linear-triangular,
or
above the
cavity
chlorophyll.
lacking, dehiscing
trilete,
on
sporophyll, irregularly
to
(outside
present
outside
mm
cuticle and
lacking
linear
glabrous,
a
quantities
large
arising
unbranched vascular strand;
septate cavities;
from
100 or more),
lobes of
triquetrous, entire, proximally winged
±
single
a
accumulate
may
(to
basally,
to
from between
arising
numerous
imbricate
terrestrial
heterosporous, herbaceous,
Sporophyte
dichotomous,
archegonia; microgametophyte
cell
wall
with
a
of
single
spore;
anther-
idium, antherozoids with 15 flagella.
About
Distribution:
smaller Pacific islands,
scattered
along
Carstensz
the
Fully
terrestrial
in
moist
grassland.
Isoetes
from 2800
plant
of hummock
certain
or
places.
to
degree of
3900
bogs
m
in
species,
Victoria.
partially
The
neoguineensis,
tarns
a
Mt.
to
125
in temperate
most
regions.
cordillera of the
central
(Mt. Jaya)
Ecology:
mainly
Fig.
I.
New
of the world,
the
except
Papuasia
Guinea
there
are
4
species,
mainland from
Mt.
1.
aquatic
Papuasian
in
still
taxa
habbemensis,
altitude, mostly
parts
In
or
are
slow-flowing
restricted
and I. stevensii
above 3300
around 3600 m altitude. The
m.
I.
to
are
waters,
high
found in
hopei
aquatic species
is
or
altitude
alpine
a
terrestrial
can
withstand
have been collected several times from almost
exposure and
dry
pools.
In
Papuasia dispersal
aquatic
Papuasian
floating
on
of spores is
species
is
the surface of the
by
primarily by
detached
tarns.
means
sporophylls,
of water;
which
one
can
mode in the
often be
seen
182
BLUMEA
The
Fig. 1.
distribution
There is
in
N
taxa.
o t e
Alston
are
or
(1959)
Shaded
production
no
hopei
roots
as
no
being
are
the
roots are
reported
The leaves of the
white,
the older
be white
to
(Hope,
above
three Papuasian
smell when fresh. This
was
algal slime, etc.,
taken
since
to
be
a
to
altitude.
Papuasian
gametophyte.
to
black,
presumably
I. stevensii, and
habbemensis,
mid-brown. The
roots
comm.).
of Isoetes collected
had
in the
of the
study
becoming
of
degree
Papuasia.
dark brown
a
by
the
author,
I.
distinctive, acrid, slightly fishy
character of the
else
m
suggest any
studies of the
pers,
species
nothing
3000
of Isoetes in
ones
habbemensis, I. stevensii, and I. neoguineensis,
of any
areas
detailed anatomical
records and
described the
1980
1,
no.
collections available
spore
cytological
no
neoguineensis
of I
growth
26,
from herbarium material. In live material of I.
entirely
I.
the
To date there has been
s :
There
Papuasia.
evidence from the
no
seasonality
of Isoetes in
VOL.
-
pond
plant
itself rather than that
shared this
unique
odour.
KEY TO THE TAXA OF ISOETES IN PAPUASIA
1.
Plants
wide
Mt.
1.
terrestrial; leaves
at
leathery,
± triquetrous distally, ±3
or more
in diameter
Carstensz
Plants
megaspores
reticulate
generally
2
±
fleshy,
finely rugulose,
and/or warty;
Megaspore
500
—
700(7
—
or
3
mm
wide
at
distally,
reticulate,
or
1 —3
irregularly
1
-
3
ornamentation
resembling prominent
mm
wide
at
the middle. Mt.
Wilhelmina (Mt.
regularly reticulate, of
warts on
the middle.
wide
and
irregularly rugulose (Plate 4, 6);
2.
Megaspore
often
mm
the
5
mm
hopei
at
the
deeply
diameter.
800)
ornamentationfinely and
—
terete
Star Mts.
2.
—
(Plate 1, 2).
1. I.
leaves thin and
aquatic;
middle;
2.
thick and
the middle; megaspores psilate, 800
even
or
proximal surfaces;
leaves
Mandala) and
I.
habbemensis
irregular relief,
leaves
generally
J.
3.
R. Croft:
of Isoetes
revision
A
ornamentation
Megaspore
than that of the trilete
in
(hoetaceae)
of
shallowly reticulate,
leaves 2
ridge (Plate 7);
—
183
Papuasiu
3
relief and lower
even
mm
wide
Mt. Giluwe and Mt. Sarawaket
3.
ornamentation deeply reticulate
Megaspore
the trilete ridge, often
mm
4.
wide
appearing
the middle. Owen
at
Leaves less than 20
alpine
4.
tarns
Leaves 35
—
Stanley
cm
Ranges
.
4.
.
I.
Isoetes
hopei Croft,
Herba rosula
longa, in
cm
ad
usque
8
3
1
25
fim
longae.
T
alta,
dense
y p
Irian
cetero
G.
plants of streams
100,
2
4
—
to
in
cm
1
—
1.5
Megasporangia:
dry,
all surfaces.
exiguis
sicco
in sicco
manifestis;
ad 6
pallide
ANU
16114
with
3
long,
corm-like rootstock
a
5
—
wide
mm
wide.
ridge
to
'hard hummock
21)
indicates
stenophylla,
to
+
in dried
800
—
875
+ 25 /mi
+ 7
cm
Megaspor-
trileta
39
—
usque
46/<m
Carstensz
Mt.,
±
8
below surface of bog.
beneath
mm
high,
to
6
broadly
in distal
absent; ligule
stomata
x
diameter, pale
/im
dark
ground,
wide and
triquetrous, especially
material;
3
mm;
grey
microspores
velum
almost
to
ornamentationotherwise
dark brown punctate;
brown when
bog
an
lacking
39
—
46
dry.
collection from Mt. Carstensz
type
in
wet areas.
Alt. 3630 m.
Poa
The
cf.
callosa,
but
indebted
to
1976a).
Styphelia
they
species.
Dr. G. S.
possibility
are
bear
occupying
superficially
no
trace
Moreover, they
Hope, after
of
a
a
new
of
are
Rare
rosette
photograph of
(Mt
I.
plant,
hopei
in
Potentilla foersteriana,
suaveolens,
Vaccinium amblyandrum, etc.,
megaspores
Alston,
A
association with Ranunculus,
among Malesian Isoetes in
my attention the
(Hope,
porca
Plateau,
Sporangia elliptic-oblong,
Microsporangia evenly
megaspores of that
am
usque albidae
1.
Notes:
I
deficiens.
3 mm; velum
middle, pale
at
dilated
broadly
megaspores
pinensis, Deyeuxia brassii,
bemensis
minusve
deficientia;ligula late
stomata
Kemabu
(CANB),
slight wings
mm
with trilete
Ecology:
unique
dilatata,
brunneae.
hard tops, succulent leaves and thick rootstock...'.
Plantago
x
100, usque ad 12
ca.
basaliter late
coriaceaque, plus
crassa
cineraceae
pallide
Distribution: Only known from
(Plate
Folia
Microsporangiaplane brunneo-punctata;microsporae
long, densely spinulose, pale
Jaya). Fig.
situ
paginam.
distalibus
partibus
rootstock, distally thick and leathery,
white when
/<m
cm, alis
ground, basally
broadly deltoid,
on
sicco
with evidence of
cm,
absent.
in
nulla.
Hope
12
to
green above the
attached
— 4
diametro, in
herb, terrestrial,
Leaves ±
7 cm infra turbarii
paginam pallida, supra perviridia,
affixa,
rheophila
var
21.
1 — 3,
Sporangia elliptico-oblonga, usque
875 /<m
sculptura
S.
2
late
of stagnant
6-3-1972.
Jaya,
Rosette
—
spinulosae,
s:
u
infra turbarii
lata,
et caudici
lata.
800
angia: megasporae
ca.
mm
in distalibus
1.5 mm
—
5
—
lata,
mm
triquetrapraesertim
deltoidea,
plate
—
terrestris; caudexcormoideusca.
medio
ca.
nov.
sp.
2
neoguineensis
4b.
1.
as
—
neoguineensis
var.
in current;
high
as
leaves 1
spreading; plants
flexible, flowing
±
I. stevensii
relief,
uneven
4a.
long,
the middle.
3.
(Plate 10,11,13,14);
stiff and
+
long,
cm
of
lakes
or
40
+ warty
or
at
(Hope,
Centrolepis philippers.
comm.).
It is
terrestrial habitat.
similar
the
to
those of
fine wrinkles
consistently
whom this
species
is
at
Isoetes
present
least
named,
on
habthe
30% larger.
for
Isoetes among his Mt. Carstensz
drawing
to
collections
184
2.
BLUMEA
Isoetes habbemensis Alston.
I. habbemensis
(A,
n.
Alston,
iso in
v.;
mm
in
broadly dilated,
basal part
Fl. Males.
to
1
+
flat
winged,
wide and
cm
to
slightly
or
Sporangia elliptic, oblong,
Megasporangia:
high,
proximal
on
low
surface,
pale
10
to
507
grey-white
±43 //m long,
the Snow Mts. and Mts.
presently
known
not
but
x
4 mm,
594
—
the
NSW), Croft
3.
Lake
recurved
material
spirit
when
dry.
and
distali
492
rangia sparsim
T y p
1972.
Plate
and
x
u s
;
1
—
6.
megaspore
S.
mm
velum
trilete
ridge
less
so
dark
sparsely
dry.
New Guinea from Lake
and
Meyer-Drees 9974, n.v.),
Carstensz
(Mt.
Jaya) (Hope,
in shallow
19 cm sed
6x4
598
/<m
Stevens
caudes
3.
(2
—
)3(
10
perviridia,
—
9440,
small
24-5-1975, Croft
usqua
35
—
late
pallide
39
pm
2. I.
isotype LAE),
both
x
80;
—
—
1
3
mm
plant
6543
56
with
(L.
LAE;
L,
LAE,
(K,
abaxialiter
1.5
mm
dense
(LAE),
spinulosae,
lata.
East Mt.
10
mm
dimidio
Sporangiaelliptico-
porca
in
pallide
per
rotundato,
deficiens.
albidae,
lineari-
numerosa,
lata, basaliter
lata et caudici
cm
velum
usque
Megasporangia:
trileta
inferioris.
ca.
30 /JW
Microspo-
sicco brunneae.
Giluwe,
3600 m, 15-8-
NSW.
megaspores
5.
2
uniformis et porca trileta
longae,
hopei Croft,
1
brunnea;
cineraceae
altitudinis
piano,
deltoidea,
pallide
aliquot usque
usque ad
minusve
plus
Folia
medium
ditto, microspore (ANU 16114, holotype CANB),
(Brass
a
9.
dilata,
visi): A, BRI, CANB, K, L,
1&
3300 m,
4)-lobatus.
Foreman LAE52251
of Isoetes. —
(LAE;
periods.
5-1975, Veldkamp
m,
and
deep)
Mostly entirely
drier
during
9441
less
cm or
altitude.
m
(LAE),
3300
longa, ad
cm
deficientia; ligula
in sicco
—
basi late
adaxialiter
cremea
diametro,
et
Scorpion,
(50
tarns
3300
—
Auriga,
Plate 7
—
plerumqueca.
microsporae
punctata;
Mt.
Mt.
slopes
nov.
sp.
distalibus
mm,
slopes
paginis omnibus reticulata,
Spores
alpine
(A, BISH, BRI, CANB, E, K, L, LAE, M, NSW, US).
proximali alato,
Isotypi (non
70 resp.;
1650.
—
in
alta, sculptura
Croft,
acuto; stomata
ad
usque
megasporae
NW.
LAE 65873
partibus
tereti, apice
oblonga,
ad
dimidio
affixa,
Mt.
on
1.5
—
of the Star Mountains. Western
3225 m, 8-1938, Brass 9440
Mts.,
aquatica, submersa;
in
gradatim
Star
populationseen).
and Lelean
Herba rosula,
late
found
3
abaxially,
surface,
brown when
western
Auriga
lakes from 3200
larger
Habbema,
Isoetes stevensii
flava
and
1
pale brown;
Microsporangia
—
with base
rootstock,
mm to
distal
on
2
long,
cm
distally,
rounded
cream to
but may be exposed
peaty sediment,
leaves).
triangularia, usque
x
of
margins
NEW GUINEA.
strongly
J. Brass 9440
1.
rooted in
aquatic,
L.
diameter, with
Mandala) ( Brass
not
30)
—
15
+
over
densely spinulose,
Scorpion
Ecology; Locally abundant
along
:
pe
Leaves several in smaller
adaxially,
or convex
Distribution: The central Cordillera of
1976a). Fig.
Ty
dark green
to
rugulose-scaberulous
Habbema and Mt. Wilhelmina (Mt.
limits
—
absent; ligule broadly deltoid,
ovate,
megaspores
irregularly
punctate; microspores
to
1.
± 15(
to
attached
broadly
concave
wide.
30
(1959)64, fig.
pale yellow basally grading
stomata
+
1
II,
(2 —)3( —4)-lobed.
distal half ± terete,
apex acute;
absent.
19, 20.
6,
—
larger plants, linear-triangular,
the middle,
at
(1945) 180;
herb. Rootstock
rosette
to numerous
wide
Plate 4
—
1980
1.
no.
LAE).
Submerged
plants
J. Arn. 26
VOL. 26.
-
(ANU 16114, holotype CANB),
x
1400; 4 & 6.
ditto, microspore (Brass
I. habbemensis
9440,
x
65
Alston,
isotype LAE),
J.
R. Croft:
A revision
of Isoetes
(lsoetaceae)
in
Papuasia
185\I
186
Submerged
plants
10
to
2
base
distally,
3
—
mm
acute;
ridge
±
39
dilated to
half
6
Notes:
Plate
16—18)
diameter, pale
known
trilete
withstand
has
and has
deep)
cm
species
exposure in
a more uneven
finely
has
scabrous rather than
neoguineensis,
The
trilete
being
ridge.
In
design, however,
reticulate rather than
single specimen
embossed with
a
reticulum of
Further collections of this
deserves separate taxonomic
specimen
NEW GUINEA. E. Mt. Giluwe. 3660 m,
15-8-1972,
m,
(BISH, LAE);
4.
I.
3450 m,
3450
(LAE).
Isoetes
m,
Mt.
Ann.
1897-8
Isoetes
Plate
8.
x
Kew Bull.
sp.
(1899)
Mo. Bot. Gard.
(1934) 169; Alston,
(1898) 149,
Fl. Mai.
nomen
Coode and
7 — 12. Spores
Pullen
Schodde
Baker.
9
II,
2833
nudum.
—
Stevens, Papua
of Isoetes.
—
7. I.
64.
I.
1790;
12.
11.
I.
neoguineensis
Baker
var.
ditto, microspore (LAE 51360, LAE),
x
species.
more
It
strongly
that of the trilete
and Katik NGF40229
ridge.
x
(LAE);
21-1-1979, Croft
van
Royen
16-7-1971,
Engler & Prantl, Nat.
in
van
Giulianetti
Sci,
Croft,
3700 m,
3600 m,
Steenis,
neoguineensis F.
Type:/).
ditto, microspore ( LAE 52251, holotype LAE),
10 &
in this
are
9846
11261
Wade &
&
11264
McVean
(LAE).
s.n.
v.
megaspore
9.
M.,
1,4(1901) 776;
Jard. Bot.
Ann
Rep.
Buit. Ill,
13
Brit. N. Guinea
(K).
Soc. Proc. 23
1470;
Pfl. Fam.
Bull.
(1972)
(LAE
52251
25.
, holotype LAE),
x
100;
ditto, microspore (Schodde 1843, LAE),
neoguineensis, megaspores (LAE 51360, LAE),
1650.
3600
708 <K,
15.
10 —
New Guinea
stevensii
that
14-9-1964, Hoogland
Posthumus
—
I.
in appearance.
26-6-1976,
(LAE);
3450 m,
122; Sadebeck in
(1959)
3800 m,
1843A
Plate
—
lower
resolve whether the Sarawaket
W. Mt. Giluwe.
(LAE);
1843 &
(1922) 211;
1
to
not
status.
(LAE).
Sarawaket, Kenzohroh,
neoguineensis
neoguineensisBaker,
Pfeiffer,
22-9-1961,
4-8-1961,
required
habit
microspores.
closely approaches
megaspores
19-9-1969, Coode, Wardle,
Stevens and Foreman LAE52251
L, LAE, NSW);
ANU 7756
are
not
which is confluent
habbemensis, being
more
height approximating
even
population
philip-
series of wrinkles
tentatively placed
having
of I.
reticulum that is
spinulose
honey-comb-like
from Mt. Sarawaket is
differs from the Mt. Giluwe collections in
it
m
dry periods.
long flowing
a
1.
Fig.
3600
to
type ( Zwickey 776,
irregular
an
philippinensis
I.
dry,
relief,
even
microspores
suggestive
are
The ornamentation of the megaspore is like that of I.
than that of the
of
3400
at
ornamentation of I. stevensii,
honey-comb-like
wide.
mm
white when
to
reticulate,
examination of the
philippinensis
mm to
distal half
velum absent.
dark punctate:
periodic
of this
megaspores
ridge. Furthermore,
in I. stevensii,
grey
1.5
+
green
dry.
than 50
(less
1940). However,
Perry,
—
10
over
from Mt. Giluwe and Mt. Sarawaket.
tarns
apparently
can
1
brown;
mostly
dark
to
abaxially,
deltoid,
pale
to
brown when
only
alpine
revealed that I.
rather than the
with the
rounded
broadly
cream
confluent with the trilete ridge, resembling
all
at
&
ligule
598 yum
—
but
long
cm
attached
broadly
adaxially,
mm,
spinulose,
The reticulate
pinensis (Merr.
flat
ridge. Microsporangia sparsely
Shallow
plants
4
x
Leaves several in smaller
19
to
ornamentation on all surfaces
Distribution: Known
altitude. The
1980
pale yellow basally grading
wide and
cm
+
absent;
to
high,
trilete
Ecology:
± 1
winged,
megaspores 492
long, densely
/tm
I.
no.
(2 —)3( —4)-lobed.
the middle,
stomata
30 fim
lower than the
—
at
elliptic-oblong,
Megasporangia:
trilete
26.
larger plants, linear-triangular,
wide
broadly
apex
Sporangia
35
in
rootstock, proximal
terete,
VOL.
herb. Rootstock
rosette
numerous
long,
cm
the
-
BLUMEA
both
x
66;
J.
R. Croft:
A
revision
of
hoetes
(Isoetaceae)
in
Papuasia
187\II
188
BLUMEA
VOL. 26,
-
Distribution:A species with
from Mt.
Range,
4a.
neoguineensis.
var.
Submerged
plants
wide
to
the middle,
at
1
winged,
absent
stomata
oblong,
6
to
30
3
x
reticulate
35
pores
800)
—
42 /an
Mt.
from 2800
the
scabrous.
4000m.
—
1
5
—
mm
velum
brown;
base
trilete
ridge,
on
Megasporangia:
Owen
Stanley
of
Range
New
and Mt.
alpine
but may be
Mostly entirely aquatic,
irregular
irregularly
dry.
eastern
Scratchley,
surface
dark punctate; micros-
Microsporangia sparsely
brown when
with trilete
reticulum of
proximal
acute;
Sporangia elliptic-
wide.
a
mm
broadly
rootstock. Proximal
absent.
distal surface
on
smaller
1 —2
long,
distally,
to
mm
cm
distal half terete, apex
in peaty sediments of shallow
Ecology: Growing
deep)
10
±
over
Mt. Albert Edward, Mt.
Dickson,
10—17
dark green
to
abaxially,
long, minutely spinulose,
Distribution: The
Strong,
as
Leaves several in
5)-lobed.
diameter, pale grey-white when dry,
/tm
height
same
and/or deeply
—
—
deltoid,
high, ornamentation
about the
relief,
4(
attached
pale
to
cream
mm,
710(
—
—
rounded
(?or few); ligule broadly
50
—
3
larger plants, linear-triangular,
broadly
Stanley
12.
—
Rootstock
adaxially,
the Owen
to
1.
Fig.
pale yellow basally grading
flat
megaspores 510
ridge
in
1980
varieties restricted
two
Victoria.
Plate 10
—
wide and
cm
±
Mt.
to
herb.
rosette
numerous
dilated to ±
half
Strong
1,
no.
Guinea
(Mt.
Victoria). Fig. 1.
(50
tarns
cm or
less
drier
exposed during
periods.
NEW GUINEA.
Owen
13-7-1974, CroJi
Giulianetti
Edward:
s.n.
3300 m,
(K);
Kanai 753570
Mt.
NSW).
only);
3600 m,
Neon
Dickson:
3500 m,
13-7-1974,
(A);
3800 m,
LAE 61483
2800 m,
22-6-1974, Craven
Craven
3070
(LAE;
2717
spirit
WEI 1569
(LAE); 3700
28-6-1974, Croft
11-12-1964, Hartley
3420 m,
13011
material).
3450 m,
Mt.
3-5-1971,
Stevens
1896,
Mt. Albert
(LAE; populationseen);
(A, BM,
Strong:
s.n.
CANB,
3450 m,
(UPNG;
K, L,
LAE,
30-4-1971,
Coode
Coode and Stevens NGF 46254
and Coode
3600
27-10-1975,
3700 m,
10-11-1970, Passer
LAE 61531
(LAE).
25-4-1971,
m,
3600 m,
(LAE);
3000-3900 m,
Scratchley:
(A, BM, CANB, K, L, LAE, NSW);
3-4-1976, Kores
specimen);
Mt.
Coode and Stevens NGF 46337
(LAE; spirit material);
5-lobed
a
4366
Basin,
3450 m,
and Stevens NGF54201
spirit material,
7-5-1971,
and Lelean
(LAE);
FAA material
Mt. Victoria:
(A, BM, CANB, K, L, LAE, NSW).
6-1933, Brass
3680 m,
27-6-1976, Croft
m,
Stanley Range.
LAE61775
LAE 51360
(LAE;
(LAE; spirit
material; CANB)
4b.
var.
Herba
rheophila Croft,
aquatica,
rosula,
var.
lata,
caudici per
rotundata,
ca.
distalibus
Sporangia oblonga,
neoguineensi
T y p
m,
Plate
x
u s
:
/.
1200;
resp.;
13—18.
61486
16 &
18.
—
45
late
cm
affixa,
teretia, apice
usque
ad 6
x
longa,
cm
11
in
acuta;
mm;
13 — 15.
foliis
in
ad medium
trahentibus.
aqua
ca.
1.5
mm
lata,
partibus proximalibus alata,
ad
basem
structure
albida,
sporarum,
in
Caudex
basi late
adaxialiter
partibus
trilobatus.
Folia
dilatata usque ad
plana,
distalibus
1.5
abaxialiter
abrupte
viridia.
amplitudo formaque .I. neoguineensi
var.
similaris.
28-6-1974.
(LAE
1.5
Plate
—
submersa, rivulara,
numerosa, angusto-linearia, 35
cm
nov.
R
Croft
Spores
of Isoetes.
, holotype LAE),
17. I.
LAE61486
(LAE),
Isotypi: L, CANB, K,
x
—
13 &
90 and
philippinensis Merr.
&
x
14. I.
neoguineensis
80 resp.;
Perry,
Neon Basin, Mt. Albert Edward, 2800
BM.
15.
Baker
var.
rheophila Croft,
ditto, microspore (LAE
megaspores
ditto, microspore (Zwickey 776, holotype A),
x
(Zwickey
2270.
776
61486,
, holotype A),
megaspores
holotype LAE),
x
110 and
x
100
J.
R. Croft: A revision
of
Isoetes
(lsoetaceae)
in
Papuasia
189\III
190
BLUMEA
Submerged
very
1.5
6x11
mm;
size,
spore
and
shape,
in
Rootstock 3-lobed. Leaves
stream.
attached
wide
distally
the
at
1.5
+
over
abaxially,
medium
to
1, 1980
no.
long, ±1.5 mm
cm
rounded
adaxially,
abruptly grading
basally,
26,
trailing
45
—
wide, broadly
cm
flat
proximally winged,
white
35
narrow-linear,
dilated to
broadly
herb with leaves
rosette
numerous,
VOL.
-
base
middle,
rootstock,
to
cm
terete, apex acute;
distally. Sporangia oblong,
green
ornamentation
for
as
I.
neoguineensis
to
var.
neoguineensis.
Distribution:
in
population
Owen
Only
known
the Neon Basin,
Stanley
in
Trailing
megaspores
those of the type
not at
that of I.
clearly
I.
variety.
plasticity
that Isoetes
Papuasia
has
in
populations
streams
otherwise
not
that
suggests
the
neoguineensis,
philippinensis
has
the still
this
an
ridges being
even more
is known about the
could show that
found in
was
other
such
plants
tarn
long flowing habit. However,
the
population
dense than
reticulate ornamentation
irregular
(Plate 16,17). Very little
develop
been
water.
philippinensis Merrill and Perry
of Isoetes, and further research
transplanted into suitable
the
However, the ornamentation of the
neoguineensis.
all confluent with the trilete ridge
phenotypic
restricted
a
basin in
grassland
below surface of
cm
resembles I.
variety
var.
neoguineensis
is
± 70
stream,
Notes: The habit of this
rather than I.
from
collection
type
1.
Range. Fig.
Ecology:
from the
extensive intermontane
an
the fact
available habitats
different
in
from
those
geographically disjunct
series
genetically
tarns.
DISCUSSION
The four New Guinea
of
populations
while
megaspore,
complex,
west to
Giluwe
east, thus: I.
uneven
hopei (smooth)
population (low
even
between
series of
geographic
a
represented by
are
central Cordillera
different
quite
represents
(pronounced
species
the
along
even
reticulate)
I.
The
of each
populations
(rugulose)
I.
neoguineensis
the
at
I. stevensii,
—
Mt Sarawaket
I.
and
other,
hopei
with
I.
at
a
decrease in the
extreme
one
and
stevensii
Mt.
population
reticulate with
neoguineensis (very pronounced
leathery
mountain
and relief from
increasing complexity
I. stevensii,
-
ornamentation of the
relief). This cline in spore ornamentationis correlated with
thickness of the leaves with the very
leaved
the
1).
I. habbemensis
—
reticulate)
—
a
(fig.
and the fine
habbemensis
I.
intermediate.
This
evidence
represent
existed
the
the
during
estimated
to
considered
strongly
remnants
of
be
depressed
sufficient
to
that
the
related
closely
less continuous
of about
glacial period
have been
to
suggests
a more or
34,000
about 1500
present
an
m
years
(Hope,
almost
New
ago when
1976b).
continuous
habitats for Isoetes. The existence of this cline suggests that the
of the genus
useful for
the basis
of megaspore
species identification,
least in the
tarn
on
Papuasian
species.
A
does
core
in the Star Mountains contains
recently
layers
collected
by
the lowermost peaty sediments. These have been dated
P.
(Hope,
some
light
on
comm.).
the
recent
A
study
of the spores
evolution of the
of
potential
subdivision
while
being
relationships,
S.
is
depression
1922),
Dr. G.
have
Hope
at
from
a
of I. habbemensis
megaspores extending
to
pers.
This
range
represent phylogenetic
species
may
the tree-line is
previous
sculpturing (Pfeiffer,
not
Guinea
cline that
east-west
along
spore
to
13,250 ±
395 years B.
the sediment profile may shed
ornamentation in this
species.