A synopsis of Ptisana Murdock ferns (Marattiaceae) in New Caledonia based on sequence data and morphology with the recognition of a new vulnerable species, P. soluta (Compton) Murdock & Perrie, comb. nov., stat. nov.
Author
Shepherd, Lara D.
Museum of New Zealand Te Papa Tongarewa, Wellington 6011 (New Zealand)
lara.shepherd@tepapa.govt.nz
Author
Murdock, Andrew G.
Innovative Genomics Institute, University of California, Berkeley, 2151 Berkeley Way, Berkeley, California 94720 (United States)
andymurdock@berkeley.edu
Author
Amice, Rémy
Independent researcher, Nouméa (New Caledonia)
amicelr@lagoon.nc
Author
Perrie, Leon R.
Museum of New Zealand Te Papa Tongarewa, Wellington 6011 (New Zealand)
leon.perrie@tepapa.govt.nz
text
Adansonia
2023
3
2023-02-20
45
3
41
59
journal article
55064
10.5252/adansonia2023v45a3
9c423299-73fd-4c27-b497-fa7b98850ed9
1639-4798
7665061
Ptisana soluta
(Compton) Murdock & Perrie
,
comb. nov., stat. nov.
(
Figs 3
;
5
)
Ptisana soluta
(Compton) Murdock & Perrie
comb. nov., stat. nov.
differs from
Ptisana attenuata
(Labill.) Murdock
in bearing leaves with smooth, mottled green-brown stipes, and laminae that are 3-pinnate proximally, 2-pinnate distally, and differs from
Ptisana salicina
(Sm.) Murdock
in bearing synangia that are removed from the margin, and laminar division as previously described.
Marattia smithii
Mett. ex Kuhn forma
soluta
Compton
,
Journal of the Linnean Society,
Botany
45: 456 (
Compton 1922
)
.
—
Type
:
New Caledonia
.
Ignambi
,
1500 ft.
,
4.VIII.1914
,
Compton
1674
(holo-,
BM
[
BM000787128
]!).
ETYMOLOGY.
—
Compton (1922)
originally described this species as
Marattia smithii
Kuhn forma
soluta
Compton
and noted the lamina character that distinguishes this taxon. The Latin “
soluta
” means “separate from adjacent parts, breaking up”, presumably in reference to its transition between 2- and 3-pinnate states.
HABITAT AND DISTRIBUTION.
—
Based on available collections,
Ptisana soluta
comb. nov., stat. nov.
is endemic to
New Caledonia
, where it is widespread but uncommon on Grande Terre. It is known from Mt. Ignambi and Mt. Panié in the northeast, near Canala in the central-east, and near Nouméa in the southwest (
Fig. 4
). One collection from Sommet Arago (
Compton 1442
, BM) may be this species, but was described as being from a population of 2-pinnate plants; this requires further investigation. Several collections note a (rain-) forest and/or mountain habitat, with recorded elevations ranging from
200 m
to
800 m
.
Based on
Fig. 4
, it seems to be on non-ultramafic substrates, although it may come at least close to ultramafics on Koghis. At Koghis,
P. soluta
comb. nov., stat. nov.
grows intermixed with
P. attenuata
and
Angiopteris evecta
. Additional study of the ecological range of
P. soluta
comb. nov., stat. nov.
, and how it may differ from
P. attenuata
, is needed.
CONSERVATION ASSESSMENT.
—
We suggest that
Ptisana soluta
comb. nov., stat. nov.
be ranked as Vulnerable (VU B1ab(i,i i,iii,iv,v)+2ab(i,ii,iii,iv,v),
IUCN 2012
), with this provisional until verified by the
New Caledonia
Plants Red List Authority. The estimates of
60 km
2 for area of occupancy and
4236 km
2 for extent of occurrence are well under the thresholds for criterion B of the Vulnerable category. The subcriteria 1b and 2b are met because of ongoing, substantive predation by rusa deer and feral pigs, as is the case with
P. attenuata
(
Endemia Red List Authority 2022
)
. The subcriteria 1a and 2a both invoke “no more than 10 locations”. The exact number of locations is unclear, particularly with the imprecision of earlier collections, but given the mobility of the deer and pig threats, known locations could be defined as:
1-2 in
the southwest, one in the central-east, and
2-4 in
the northeast (see
Fig. 4
).
Ptisana soluta
comb. nov., stat. nov.
is unprotected by legislation, but occurs within reserves at Thy Valley and Mt. Panié. The priority for its management should be searching for new sites and surveying known localities, particularly the accessible Koghis and also Ignambi, where
Compton (1922)
said this
form was
“abundant”.
DESCRIPTION
Fronds 3-pinnate proximally, transitioning to 2-pinnate distally, at least
4 m
long, bearing 4-6 pairs of opposite pinnae on mature fronds, the terminal pair forking at the frond apex. Stipe circular in cross-section, smooth, mottled green-dark brown, subtended by paired stipules, round, shallowly divided to nearly entire with ragged margins. Swollen pulvini present at the base of all segments, green, smooth. Ultimate segments
35-104 mm
long ×
6.5-19.1 mm
wide on 3-pinnate portions,
163-295 mm
long ×
13.7-35.6 mm
wide on 2-pinnate portions, oblong with acuminate apices. Laminae dark green above, lighter below, herbaceous-coriaceous, with occasional ciliate scales abaxially along veins and midribs. Veins free,
c.
2 mm
apart, occasionally dividing once. Leaf margin sub-entire-minutely serrate, more clearly serrate near apex. Synangia green when immature, tan-brown after opening, one per vein, submarginal, set back from leaf margin by
1-3 mm
,
2-3.5 mm
long ×
c.
1 mm
wide, longer and with more locules on larger segments, receptacles bearing short, branched, uniseriate hairs.
Ptisana soluta
comb. nov., stat. nov.
Balansa 1559
, Canala,
20.XI.1869
, P[P00522621, P00522622, P00522623, P00522624, P00522625, P00522626];
Braithwaite
559
, no locality or date, NOU[
NOU056668
,
NOU056674
,
NOU056675
];
Buchholz
1230
,
Thy River
,
20.X.1947
, P[P00518375],
UC
[799340];
Compton
1674
,
Ignambi
, 1914, BM[
BM000787128
] [
holotype
of
Marattia smithii
f.
soluta
];
Foster
156
,
Ignambi
,
12.VI.1956
,
UC
[
UC1053924
];
Franc
1911
[sic] (
Rosenstock
122
), no locality or date, P[P01365760];
Franc
2376
,
Monts Koghis
,
6.X.1929
, P[P00522537];
Franc
2377
,
Monts Koghi
,
6.X.1929
, P[P00518354];
Franc
749
,
Mts Koghis
,
IV.1912
, P[P01365700, P01365758, P01365759];
Franc
749
,
Monts Koghis
,
25.VII.1912
, P[P00522537, P0522637, P01365699];
Franc
749
, no locality or date,
UC
[
UC392870
];
Franc
s.n.
,
Mont Koghi
,
IV.1911
, P[P00522539, P00522540, P0522541, P0522542];
MacKee
4795
,
Mt Ignambi
,
12.VI.1956
, P[P00522796];
no collector, locality, or date, P[P00522786];
Pancher s.n.
,
Montrouzier
, 1855, P[P00518388];
Perrie
et al. 8330
,
Koghis
,
20.X.2019
,
WELT
[
P030314
], NOU[
NOU090683
,
NOU106931
];
Pinard
s.
n.,
Nord
, 1856, P[P00522776];
Schmid
17
,
Koghis
,
14.I.1965
, NOU[
NOU056662
];
van derWerff &
McPherson
15907
,
Mt. Panié
,
23.X.1999
, NOU[
NOU056685
],
UC
[
UC1740300
];
Vieillard
1681
,
Balade
, no date, P[P0522758, P00522759, P01365709];
Vieillard
1681
,
Pouébo
, no date, BM[
BM000785905
].
Possible
P. soluta
comb. nov., stat. nov.
(not mapped)
Balansa 1560
, Canala,
20.XI.1869
, P[P00522544, P00522545];
Balansa 801
, Mont Mi,
16.III.1869
, P[P00522546, P00522547];
Compton
1442, Mont Arago,
14.VII.1914
, BM[BM000785888];
MacGillivray 29
, no locality,
VI.1858
, P[P01646578];
MacGillivray 729
, no locality,
VIII.1858
, P[P00522642, P00522797], BM[BM000785896];
Pancher 1680
, no locality or date, P[P00522781];
Pancher s.n.
no locality, 1870, P[P00522534, P00522536];
Pancher s.n.
, no locality or date, P[P00522459, P00522780, P00522782, P00522783];
Suprin 1481
, Thy,
20.XI.1981
, P[P01365254].