Phegopteris excelsior (Thelypteridaceae): A New Species of North
American Tetraploid Beech Fern
Nikisha R. Patel,
and Arthur V. Gilman
Pringle Herbarium, Department of Plant Biology, 111 Jeffords Hall, University of Vermont,
63 Carrigan Drive, Burlington, Vermont 05405, U.S.A.
Department of Ecology and Evolutionary Biology, University of Connecticut, 75 N. Eagleville Rd.,
Unit 3043, Storrs, Connecticut 06269, U.S.A.
*Author for correspondence: firstname.lastname@example.org
ABSTRACT. Since the 1970s, an apomictic tetraploid
beech fern (genus Phegopteris (C. Presl) F´ee) has been
known in northeastern North America. Previously
published isozyme data suggest that this lineage is of
allopolyploid origin involving long beech fern (P.con-
nectilis (Michx.) Watt.) but not broad beech fern
(P. hexagonoptera (Michx.) F´ee), as originally hypoth-
esized. Its second progenitor remains unknown. We
performed a principal components analysis of the apo-
mict and its North American congeners to elucidate
morphological differences between them. We recognize
the apomictic tetraploid at specific rank as P. excelsior
N. R. Patel & A. V. Gilman and provide an illustration, a
range map, a list of exsiccatae, and a key to Phegopteris
species of North America.
Key words: Allopolyploid, apogamy, apomixis, cryptic
species, hybrid speciation, Phegopteris, Thelypteridaceae.
The genus Phegopteris (C. Presl) F´ee as currently
recognized includes five species in North America,
Europe, and Asia (Holttum, 1969; Jermy & Paul,
1993; Smith, 1993; Kim et al., 2004; Lin & Smith,
2013; Fraser-Jenkins et al., 2015; Almeida et al., 2016).
These are P. connectilis (Michx.) Watt, P. hexagonop-
tera (Michx.) F´ee, P. decursive-pinnata (H. C. Hall) F´ee,
P. koreana B. Y. Sun & C. H. Kim, and P. tibetica
Of these, Phegopteris connectilis has the widest dis-
tribution, known across North America, Europe, and
Asia, and ranging from montane Taiwan (Lin & Smith,
2013) to slightly north of the Arctic Circle in Europe
(Tolmachev, 1995) and Alaska (Smith, 1993). It is
known primarily as a triploid (Manton, 1950; L¨ove &
L¨ove, 1961, 1976; Mulligan et al., 1972; Mulligan &
Cody, 1979; Smith, 1993; Ivanova & Piekos-Mirkowa,
2003), which has an apomictic life cycle (Manton, 1950;
Mulligan et al., 1972) with premeiotic endomitosis
(sensu Grusz, 2016). The base chromosome number
in this group is 30; being apomictic, both sporophytic
and gametophytic tissues of triploid P. connectilis have
90 chromosomes (n52n590). There is also a diploid
(2n560), sexual race of P. connectilis in central Japan
(Hirabayashi, 1969; Matsumoto, 1982; Matsumoto &
Yano, 1989). With its multiple ploidies and reproduc-
tive modes, P. connectilis constitutes a species complex
with circumpolar distribution.
Phegopteris hexagonoptera, endemic to eastern North
America, is a sexual diploid (Britton, 1953; Wagner,
1955; Smith, 1993). Two other species are confined to
Asia: P. koreana, endemic to Korea, is an apomictic
tetraploid (4n5120; Kim et al., 2004), and P. tibetica,
widespread across China, Nepal, and India (Lin &
Smith, 2013; Fraser-Jenkins et al., 2015), is so far
without information on ploidy or reproductive biology.
The fifth species, P. decursive-pinnata, is widely distrib-
uted in China, Japan, Korea, and Vietnam (Lin & Smith,
2013), and includes diploid, triploid, and tetraploid
cytotypes (Mitui, 1976; Masuyama, 1979, 1986). This
species was recently reported as naturalized in the south-
eastern United States (Florez-Parra & Keener, 2016).
Mulligan et al. (1972) reported an apomictic tetra-
ploid beech fern (n52n5120), discovered by L. Cinq-
Mars at Rougemont, near Montreal, Quebec, and grown
in cultivation at the Agriculture Canada Central Exper-
iment Farm in Ottawa. In addition to investigating its
chromosome complement, Mulligan et al. (1972) qual-
itatively scored characters associated with blade shape,
shape and color of scales on the abaxial surface of
fronds, and extent of rachis wings for several specimens
of this plant and of the two beech ferns native to eastern
North America, Phegopteris connectilis and P. hexago-
noptera. They concluded that the tetraploid was likely
an allopolyploid derived from a hybridization event
between these two, both of which co-occurred with
the putative hybrid at Rougemont, and hypothesized
that the event involved a haploid egg from P. hexago-
noptera and a triploid sperm from P. connectilis. Such a
hybrid, with unbalanced genomes, would fail at normal
meiosis but could bypass normal meiosis via premeiotic
endomitosis to achieve a successful apomictic life cycle
VERSION OF RECORD FIRST PUBLISHED ONLINE ON 4NOVEMBER 2019 AHEAD OF WINTER 2019 ISSUE.
doi: 10.3417/2019409 NOVON 27: 211–218.
(Evans, 1969). Later, similar tetraploids were found in
Nova Scotia and New Brunswick, but, given their re-
semblance to P. connectilis, Mulligan and Cody (1979)
included these tetraploids in a broad concept of that
While the morphology of the tetraploid apomict is
suggestive of a mixture of genomes inherited from
Phegopteris connectilis and P. hexagonoptera, that hy-
pothesis was not corroborated by evidence from molec-
ular data. Driscoll et al. (2003) examined six isozymes
from populations in Vermont and found similar mobility
between the isozymes of P. connectilis and those of the
tetraploid but limited similarity in mobility between
those of the tetraploid and P. hexagonoptera. Driscoll
et al. (2003) also carried out a morphological analysis,
including more characters than used by Mulligan et al.
(1972), which also suggested significantly more simi-
larity between the tetraploid and P. connectilis than
between the tetraploid and P. hexagonoptera. Conse-
quently, Driscoll et al. (2003) suggested that the tetra-
ploid may have a hybrid origin involving P. connectilis
but not P. hexagonoptera. Recently, Patel (2018) pre-
sented plastid data that also suggested shared maternal
origins between P. connectilis diploids, triploids, and
this tetraploid, on the basis of identical rps4-trnS and
psbA sequences. Furthermore, both isozyme data in
Driscoll et al. (2003), and biparentally inherited nuclear
markers (Patel, unpublished data), demonstrate hetero-
zygosity, suggesting again that the apomictic tetraploid
is an allopolyploid with P. connectilis as one progenitor
and an unknown species as the other.
Cryptic species abound among ferns, and many such
lineages have been discovered in groups in which
hybridization and apomixis are prevalent (Paris et al.,
1989; Adjie et al., 2007). Allopolyploids, both sexual
and apomictic, are often difficult to distinguish mor-
phologically from their progenitors (Barrington et al.,
1989) or other closely related species. The main prob-
lems posed by cryptic taxa are: (1) the uncertainty of
positive identification and (2) the difficulty of commu-
nication regarding them. With the North American
tetraploid beech fern now characterized by chromosome
number, metabolic enzymes, DNA sequences, and prob-
able maternal ancestry, we address the first problem by
undertaking additional morphological study to charac-
terize it, as best possible, for field and herbarium iden-
tification, and by providing a key and description. The
second problem we address by recognizing the tetraploid
as a new species and providing a name, Phegopteris
excelsior N. R. Patel & A. V. Gilman.
MATERIALS AND METHODS
We studied Phegopteris connectilis from across its
North American range, some specimens from Europe,
and both triploid and diploid specimens from Japan,
revising collections at GH, MICH, MT, NEBC, NY, UC,
and VT. We also sampled P. hexagonoptera from the
northeastern and midwestern United States. Included in
our sample were two tetraploids with documented chro-
mosome numbers, including one collection (Sherk &
Cinq-Mars 437, MICH) from the original Rougemont
station, and one from Nova Scotia verified by Cody
(Cody 20242, MICH), both indicated in the principal
components analysis (PCA). Additional putative spec-
imens of tetraploids field-collected by Gilman or seen in
regional herbaria were identified on the characters
provided by Driscoll et al. (2003). We scored 19
quantitative morphological characters (Table 1). We
performed a PCA on 57 samples (Appendix 1), scoring
19 characters ranging from features of scales to those of
pinnae. We implemented the PCA in R v. 3.4.4 using
the package ggplot2 (Wickham, 2016). Our analysis
included accessions of P. connectilis 3x,P. connectilis
2x,P. hexagonoptera, and the known or putative tetra-
ploids, hereafter referred to as P. excelsior. Spores were
measured from four collections of P. excelsior, two of
triploid P. connectilis and one of diploid P. connectilis;
30 spores were collected and measured when possible,
though for two specimens of P. excelsior, 15 and 20 were
In the morphological PCA involving Phegopteris
connectilis (2xand 3x), P. hexagonoptera, and P. ex-
celsior, we found substantial overlap among all three
clusters, with diploid and triploid P. connectilis clus-
tering together. The clusters of points representing P.
excelsior are partly intermediate between P. connectilis
and P. hexagonoptera (Fig. 1). In the analysis, the points
representing the holotype and the specimens verified
as tetraploid by Mulligan et al. (1972) are within the
confidence interval of P. excelsior, slightly closer to the
P. connectilis cluster than to the P. hexagonoptera
The first and second principal components accounted
for the largest proportion of variance in the analysis
(66.3%; Fig. 1). The characters with strongest weight
based on eigenvalues were the length of the first pinna
and the length of the second pinna.
Our PCA shows the tetraploid in a generally inter-
mediate position between Phegopteris connectilis and
P. hexagonoptera (Fig. 1), which would support the orig-
inal hypothesis that it was the product of a hybrid event
between those two species. However, knowing that
isozyme data indicate P. hexagonoptera is not a pro-
genitor, we also find support for our alternative
Table 1. Characters scored for principal components analysis (PCA).
1. Length of stipe
2. Length of blade
3. Length of gap between two lowest pinna pairs
4. Number of pinna pairs, including those diminished to lobes at summit of blade
5. Length of basal pinna
6. Number of basiscopic pinnules on basal pinna, including those diminished to lobes at tip of pinnule
7. Length of suprabasal pinna
8. Number of basiscopic pinnules on suprabasal pinna, including attenuating distal segments
9. Width of basal pinna, widest point
10. Width of suprabasal pinna, widest point
11. Number of pinnules on a 5-cm segment near middle of the third pinna
12. Distance from base of sinus to pinna rachis (measured on basiscopic side of largest pinnule)
13. Length of largest pinnule measured along midvein from base of sinus to tip
14. Width of largest pinnule measured from sinus base to sinus base
15. Width of largest pinnule measured 2 mm from tip
16. Number of sori on largest pinnule (including any on tissue below sinuses)
17. Distance from center of sorus to margin, largest pinnule, first basiscopic sorus above base of sinus
18. Number of sporangia per sorus, largest pinnule, first basiscopic sorus above base of sinus
19. Number of indurated cells in annulus in a randomly selected sporangium
Figure 1. Principal components analysis (PCA) of Phegopteris connectilis (Michx.) Watt., P. hexagonoptera (Michx.) F´ee, and
P. excelsior N. R. Patel & A. V. Gilman. Two diploid P. connectilis from Japan are indicated with the number 2. The holotype for
P. excelsior,Gilman 18021 (VT), is indicated with the letter T, and the specimens Sherk & Cinq-Mars 437 (MICH) and Cody 20242
(MICH), plants originally discussed by Mulligan et al. (1972) and verified by chromosome counts, are indicated by the letter C.
Volume 27, Number 4
Patel et al. 213
Phegopteris excelsior (Thelypteridaceae)
hypothesis. The tetraploid shares more overlap with
P. connectilis than with P. hexagonoptera in the PCA,
and similarities with the latter taxon are driven in part by
overall larger size. Although its second presumed pro-
genitor is missing, Driscoll et al. (2003) and our PCA
suggest that the parent could be even taller than
P. excelsior, have narrower basal pinnae, and in general
have more exaggerated P. connectilis features than
any P. hexagonoptera features, assuming that the
morphology of the tetraploid is intermediate between
The taxonomic rank of apomictic lineages has varied,
especially in angiosperms, but Majesk´y et al. (2017)
recommend recognition of allopolyploid apomicts at the
rank of species, and, in ferns, sexual allopolyploids are
usually so treated (see examples in Grusz, 2016).
Mulligan and Cody (1979) preferred to retain the tet-
raploid as part of Phegopteris connectilis, pointing to-
ward the cryptic nature of its morphology. However, it
clearly shares only a portion of its genome with triploid
P. connectilis and our results indicate that the morpho-
logical distinctions are subtle but consistent. Together,
these factors provide substantial justification for recog-
nition at species rank (H¨orandl, 2018).
We have examined images of Michaux’s collections of
Polypodium connectile Michx. from Canada, and Poly-
podium hexagonopterum Michx. from the southeastern
United States, both at the Museum of Natural His-
tory, Paris (P not seen, photos at HUH!; see links in
Blackwell et al., 2018). These specimens were noted as
types of their respective names by Morton (1967). The
specimen of Polypodium connectile clearly conforms to
the triploid Phegopteris connectilis and the specimen of
Polypodium hexagonopterum to the diploid Phegopteris
hexagonoptera. We have also seen an image of the
lectotype, chosen by Parris and lectotypified by Jonsell
and Jarvis (1994), of Polypodium phegopteris L., a
heterotypic synonym of Phegopteris connectilis. That
specimen is in the Clifford Herbarium at the Natural
History Museum, London (BM, image!), and exhibits
morphology consistent with the triploid Phegopteris
connectilis. We are not aware of any other heterotypic
synonyms of P. connectilis s.l. and recognize the tetra-
ploid apomictic beech fern of northeastern North Amer-
ica as a heretofore unnamed, new species.
Phegopteris excelsior N. R. Patel & A. V. Gilman,
sp. nov. TYPE: U.S.A. Vermont: Caledonia Co., St.
Johnsbury, E side of Goss Hollow Rd. near the
Sleeper River, 44°45.071719N, 72°3.6319W, in
upland Thuja occidentalis forest with Phegopteris
connectilis,Gymnocarpium dryopteris (L.) Newman
&Parathelypteris noveboracensis (L.) Ching, con-
firmed as tetraploid by flow cytometry, 8 July 2018,
A. V. Gilman 18022 (holotype, VT!; isotypes,
BRIT!, DAO!, MAINE!, MICH!, NEBC!, NHA!,
NY!, UC!, US!). Figure 2.
Phegopteris excelsior N. R. Patel & A. V. Gilman inter
congeneros Americae borealis P. connectili (Michx.) Watt
simillima, sed ab ea frondium magnitudine majore, lamina
ambitu triangulari (vs. ovata), pinnis proximalibus minus
declinatis et angustioribus longitudinis cum latitudine propor-
tione plerumque 5 (vs. 4) atque sporarum longitudine mediocri
64 mm (vs. 55 mm) distinguitur.
Long-lived, terrestrial, perennial, leptosporangiate
ferns with an apomictic life cycle. Roots fibrous, black-
ish. Rhizome terete, subterranean, long-creeping,
branching to form loose colonies, dull blackish
brown, smooth, with few, scattered, ovate scales
with elongate cells. Fronds monomorphic, decidu-
ous, (37–)50–60(–70) cm. Stipes spreading-erect to
erect, (185–)280–370(–445) mm, stramineous; ves-
titure of stipes, rachides, and costae composed of
both scales and hairs; scales stramineous to pale-
castaneous, basally affixed, lanceolate to ovate, to
1.5 35 mm, especially abundant, overlapping, pale
colored and wide (up to 50 cells wide) on newly
developing, tightly coiled croziers but more scat-
tered, smaller, and darker colored on mature frond,
often fugacious; vestiture also includes smaller,
narrow scales 2 to 3 cells wide with edges and
common, spreading, hyaline, acicular hairs. Lami-
nae 6broadly deltate, especially when pressed,
widest at base, length (170–)225–280(–440) mm,
breadth (144–)206–256(–290) mm, usually ca.
1.053as long as wide, tapering to an acuminate,
shallowly crenulate tip; pinnate-pinnatifid to bipinnate-
pinnatifid; ultimate segments entire, crenate, or very
shallowly lobed; vestiture of laminar surfaces only of
hyaline acicular hairs. Pinnae 21 to 39 pairs, average
29 pairs, proximal ones narrowly lanceolate, distal ones
elongate-triangular, gradually reduced to broadly trian-
gular lobes, then to rounded lobes, finally to low
crenations; proximal pair of pinnae (72–)103–
128(–145) mm 3(18.0–)22.0–28.0(–36.5) mm,
widest at or below middle, on average 0.23as wide
as long, in life slightly deflexed, not basiscopically
winged to rachis, acroscopically winged but wings not
confluent with those of next pinna pair; suprabasal
pinnae winged to rachis both basiscopically and ac-
roscopically, wings confluent. Sori exindusiate, 0 to
33/pinnule, average 15/pinnule, with 1 to 22, average
15, sporangia, subterminal on vein branches, round to
slightly oblong; sporangia glabrous or with 1 to several
scattered hyaline acicular hairs; annulus vertical, with
12 to 15 indurated cells. Spores reniform, monolete,
averaging 64 mm, ranging 53–75 mm. Gametophyte:
antheridia functional. Chromosomes n5120 in both
gametophytic and sporophytic tissues.
Figure 2. A–C. Habits. —A. Phegopteris excelsior N. R. Patel & A. V. Gilman (Gilman 98067 & Lambert, VT). —B.
Phegopteris connectilis (Michx.) Watt. (Gilman 2K123, VT). —C. Phegopteris hexagonoptera (Michx.) F´ee (Gilman 2K082, VT).
D–F. Close-ups of basal pinnae. —D. Phegopteris connectilis (Gilman 2K123, VT). —E. Phegopteris excelsior (Gilman 98067
& Lambert, VT). —F. Phegopteris hexagonoptera (House 289434, UC). The approximate basal pinnae length:width ratio for
P. hexagonoptera is 3:1, for P. connectilis 4:1, and for P. excelsior 5:1. The basal pinnae of P. connectilis and P. excelsior are
usually widest below the middle, and those of P. connectilis are usually widest above the middle.
Volume 27, Number 4
Patel et al. 215
Phegopteris excelsior (Thelypteridaceae)
Range and habitat. Phegopteris excelsior is known
from Nova Scotia and New Brunswick west to southern
Quebec, south to central New England and eastern New
York (Fig. 3). Phegopteris excelsior generally grows in
deciduous or coniferous forests often comprising tree
species that prefer calcareous soils (e.g., Acer saccharum
Marshall, Thuja occidentalis L.).Local topography is often
sloping, near but not immediately along small streams or
small rivers (not within the annual flood zone), not upper
montane or alpine. Microsites are terrestrial (not epipe-
tric); soils are often loam or fine sandy loam of circum-
neutral reaction. Three current populations in Vermont
occur on soils described as having pH 5.1–7.3 in the
upper stratum, and a fourth population is on soil with pH
4.5–6.5 (NRCS, 2018). Wherry (1921) found P. connec-
tilis to be indifferent to soil reaction, but P. excelsior
appears to favor circumneutral soils.
Etymology. The epithet is a Latin comparative
adjective meaning “higher”or “taller”and refers to
the habit of the species, which is usually taller than
Notes. Phegopteris excelsior is an apomict of allo-
polyploid origin, putatively involving the most morpho-
logically similar taxon, P. connectilis, as a progenitor.
The most salient characters are the larger overall size of
its fronds, blades that are more triangular, especially
notable when pressed flat (those of P. connectilis when
pressed flat are teardrop shaped with more or less
elongate tips and rounded bases), and proximal pinnae
that are slightly less downward-directed and narrower,
the width-to-length ratio typically being 1:5 versus 1:4
in P. connectilis. Among cryptic characters, spore size is
useful in distinguishing the tetraploid P. excelsior from
both diploid and triploid cytotypes of P. connectilis.
Phegopteris excelsior spores average 64 mm long, rang-
ing 53–75 mm, whereas triploid P. connectilis spores
average 55 mm long, ranging 43–69 mm, and diploid
P. connectilis spores average 42 mm long, ranging
25–48 mm. Phegopteris excelsior also differs from
P. connectilis in its nuclear DNA sequences and metabolic
Paratypes. CANADA. Nova Scotia: Cape Breton, Great
Bras d’Or, Victoria Co., Baddeck, 2–24 Aug. 1946, Scamman
4124 (GH); Kings Co., Kentville Ravine, 19 Oct. 1980, Hersey
& Newell s.n. (GH); Kings Co., Lower Blomidon, coniferous
wooded slope, 14 Aug. 1971, Cody 20242 (MICH); Pictou Co.,
Pictou, 8 mi. N of old Hwy. 4 on rd. to W Branch River John,
rich moist mixed woods, 3 July 1973, Cody 23302 (MICH).
Qu´ebec: Laval, St. Francois, mosaic des buttes s`eches et
d´epressions humides sur/dans lesquelles dominant respective-
ment les ´erables `a sucre ou argent ´e, 4 June 2013, Claude &
Munger 13-116 (MT); Lanaudi`ere, RCM Mattawinie, St.
Michele-des-Saintes, sous-bois humides, 24 June 1955, Fr.
Louis-Alphonse s.n. (MT); Estrie, RCM Memphr´emagog, Lake
Memphremagog, Gibraltar, rich wet woods, 5 Aug. 1903,
Churchill s.n. (GH); Mont´er´egie, RCM Rouville, Rougemont,
N side, large clump along stream in woods at 600-ft. elevation,
7 July 1965, Sherk & Cinq-Mars 437 (MICH); RCM Rouville,
Rougemont, [ex horto Central Experiment Farm, Ottawa], Cody
21216 [5Cinq-Mars No. 3] (DAO). U.S.A. Connecticut:
Hartford Co., Windsor, Rainbow, 14 Aug. 1905, Weatherby s.n.
(NEBC). Maine: Aroostook Co., Mars Hill township, N slope of
Mars Hill, 28 July 2004, Gilman 04104 (VT); Franklin Co.,
Strong, 20 July 1966, Seymour 24090 (VT); Hancock Co.,
Great Pond, Dow Pines Recreation Area, E end of Great Pond,
small cedar swamp, 19 June 2008, Gilman 08030 & Famous
(VT); Kennebec Co., Manchester, Allen Hill, rich woodlands,
15 June 1999, Gilman s.n. (VT); Knox Co., Washington, along
logging rd. on the N slope of Patrick Mtn., 29 June 1998,
Gilman 98067 & Lambert (VT); Oxford Co., Bethel, 31 Aug.
Figure 3. Range of Phegopteris excelsior N. R. Patel & A. V. Gilman, based on localities of specimens examined and created
using Simplemappr (Shorthouse, 2010).
1926, Wheeler s.n. (NEBC); Piscataquis Co., [Eliotsville], Ship
Pond [Lake Onawa], 1897, Brown s.n. (UC); Waldo Co.,
[Lincolnville], N shore of Megunticook Lake, wet depression
in cut-over mixed coniferous hardwood forest, 7 Aug. 1951,
Friesner 24499 (MICH); Washington Co., T29 MD, rich open
woods, 12 Aug. 1939, Knowlton s.n. (NEBC). Massachusetts:
Essex Co., Essex, 11 Aug. 1877, Robinson s.n. (GH); Franklin
Co., Northfield, 7 Oct. 1935, Smith & Hodgdon s.n. (Planta
Exsiccata Grayana No. 604: GH). New Hampshire: Rockingham
Co., North Hampton, June 1896, Eaton s.n. (GH). New York:
Delaware Co., s.d., Gilbert s.n. (GH). Vermont: Bennington Co.,
Dorset, 1904, Terry s.n. (VT); Caledonia Co., Orleans Co.,
Westmore, Willoughby, 10 Sep. 1904, Kennedy s.n. (NEBC);
Washington Co., Northfield, along woods rd., S end of Paine
Mtn., 2 Sep. 1993, Gilman 93257 (VT); 29 Aug. 2001, Driscoll
KEY TO NORTH AMERICAN PHEGOPTERIS
1. Blades of fronds elongate, widest toward the middle . . .......................P. decursive-pinnata (H. C. Hall) F´ee
19. Blades of fronds widest at the base.
2. Blades of fronds usually slightly wider than long; all pinnae, including proximal pair, winged to rachis; proximal
pinnae (2–)33as long as wide .............................................P. hexagonoptera (Michx.) F ´ee
29. Blades of fronds longer than wide; pinnae winged to rachis except proximal pair not winged to rachis (rarely, more
than one proximal pinna pair not winged in P. connectilis); proximal pinnae 4–53as long as wide.
3. Blade outline ovate, proximal pinnae strongly declined and adaxially inflexed, average 43as long as wide;
spore length averaging 55 65.4 mm......................................P. connectilis (Michx.) Watt
39. Blade outline triangular, proximal pinnae slightly to moderately declined and adaxially inflexed, average
53as long as wide; spore length averaging 64 64.6 mm.........P. excelsior N. R. Patel & A. V. Gilman
Acknowledgments. We thank current and past
members of the Barrington Lab at the University of
Vermont, particularly David Barrington, Heather Dris-
coll, Michael Sundue, Cathy Paris, and Weston Testo for
discussions and manuscript review; Morgan Southgate
confirmed the ploidy level of the type by flow cytometry.
We also thank the Pringle Herbarium (VT) for facilities
and helpful staff, including Eunice Froeliger, for arrang-
ing loans, and the curators and staff of other herbaria
including Chuck Davis, Lisa Standley, and Walter
Kittredge (HUH including GH and NEBC), Matt
Pace, Robbin Moran, and Lucy Klebieko (NY), Anton
Reznicek (MICH), Alan Smith (UC), and Heather Cole
(DAO). We thank Sadamu Matsumoto for his contribution
of specimens and karyological information (NMNS). We
also thank Bruce Baldwin, Alan Smith, and an anony-
mous reviewer for helpful comments on the manuscript.
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Appendix 1. Specimens measured for principal components
analysis (PCA). AVG refers to the private herbarium of Arthur
V. Gilman, which is not listed in Index Herbariorum.
Phegopteris connectilis. CANADA. Labrador: Perret
Trickle, Potter & Brierly s.n. (GH). Newfoundland: Mt.
Moriah, Fernald, Long & Dunbar s.n. (GH). Ontario:
Thunder Bay, Tryon, Tryon & Faber 4931 (GH). Prince
Edward Island: Charlottetown, Fernald & St. John
s.n. (GH). Quebec: Magadalen Islands, St. John s.n.
(GH). GREENLAND. Godthaab Fjord, Porsild s.n. (GH).
U.S.A. Alaska: Kuskokwim, Drury s.n. (GH); Juneau, Scam-
man 1532 (GH); Mt. McKinley, Vierek s.n. (GH). Maine:
Westmanland, Seymour 23195 (VT). Michigan: Mackinaw Co.,
Fawcett 300 (MICH, VT); Marquette Co., Harrison s.n. (GH);
Eaton Co., Wagner 63068 (GH). New Hampshire: Colebrook,
Pease 10,473 (NEBC). Vermont: Marshfield, Gilman 01032
(AVG); Waterford, Gilman 96087 (AVG); Northfield, Gilman
96132 (AVG); Danville, Gilman 96137 (AVG); St. Johnsbury,
Gilman 96286 (AVG); Wallingford, Wilmot 127 (VT). Wisconsin:
Solon Spring, Somerville 3413 (GH). JAPAN. Mt. Futago,
Boufford 23464 (confirmed diploid) (A); Mt. Kiso, Matsumoto
130924-07 (confirmed diploid) (GH); Senjogahara Moor,
Boufford 23382 (confirmed triploid) (A); Mt. Fuji, M. Furuse
s.n. (confirmed triploid) (A).
Phegopteris excelsior. CANADA. Nova Scotia: Lower Blo-
midon, Cody 20242 (MICH); Kings Co., Hersey & Newell
s.n. (GH). Quebec: Hatley, Churchill s.n. (GH); Gibraltar,
Churchill s.n. (GH); Hatley, Knowlton s.n. (GH); St. Gregoire,
Rouleau et al. s.n. (GH); Mt. Rougemont, Sherk & Cinq-Mars 437
ex cult #65374 (MICH). U.S.A. Connecticut: Windsor, Clark
s.n. (larger of twospecimens on the sheet) (NEBC). Maine: Mars
Hill, Gilman 04104 (VT); Cooper, Gilman 06050 (AVG); Molun-
kus, Gilman 2K199 (AVG); Washington, Gilman 96087 (AVG);
Bucksport, Gilman 97261 (AVG); Litchfield, Gilman 98018
(AVG); Strong, Seymour 24090 (VT). New York: Delaware
Co., B. D. Gilbert s.n. (GH). Vermont: Cabot, Gilman 01142
(AVG); St. Johnsbury,Gilman 18021 (holotype) (VT); St. Johns-
bury, Gilman 96061 (AVG); East Montpelier, Gilman 96118
(AVG); Waterford, Gilman 96248 (AVG); St. Johnsbury, Rooney
s.n. (VT); Dorset, Terry s.n. (VT).
Phegopteris hexagonoptera. U.S.A. Illinois: Jackson Co., S.
R. Hill 34847 (VT). Maine: Washington, Gilman 97127
(AVG). Massachusetts: Belchertown, H. Churchill s.n.
(VT). New York: Lake George, Evans s.n. (VT). Vermont:
South Hero, Gilman 14057 (AVG); Charlotte, Gilman 2K082
(AVG); Charlotte, Gilman 2K083 (AVG); Charlotte, Gilman
93145 (AVG); Shelburne, Gilman 98232 (AVG). Washington,
D.C.: Corwin s.n. (VT).
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