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Phedimus daeamensis (Crassulaceae),
a new species from Mt. Daeam in Korea
Tae-Young Choi1*, Dong Chan Son2*, Takashi Shiga3, Soo-Rang Lee1
1Department of Biology Education, College of Education, Chosun University, Gwangju 61452, Republic of
Korea 2Division of Forest Biodiversity and Herbarium, Korea National Arboretum, Pocheon 11186, Republic
of Korea 3Faculty of Education, Niigata University, Niigata, Japan
Corresponding author: Soo-Rang Lee (ra1130@hotmail.com, ra1130@chosun.ac.kr)
Academic editor: Yasen Mutafchiev|Received 22 February 2022|Accepted 28 September 2022|Published 3 November 2022
Citation: Choi T-Y, Son DC, Shiga T, Lee S-R (2022) Phedimus daeamensis (Crassulaceae), a new species from Mt.
Daeam in Korea. PhytoKeys 212: 57–71. https://doi.org/10.3897/phytokeys.212.82604
Abstract
Phedimus individuals from Mt. Daeam, once referred to as Phedimus sikokianus, exhibit certain morpho-
logical characters that are unique within the genus. Phedimus is one of the most notorious groups for taxo-
nomic problems due to the high morphological variation found in leaf shape, stem numbers, phyllotaxis
and seed structure. Taxa in Phedimus also easily hybridize, further leading to taxonomic confusion. To
carefully conrm the identity of the putative new species from Mt. Daeam, we examined morphological
characters from ~100 herbarium sheets of six closely related Phedimus species. A molecular phylogenetic
approach was also employed to delimit the species boundary and infer the phylogenetic relationships
among the seven Phedimus species, including the species from Mt. Daeam. Both morphological and mo-
lecular phylogenetic results indicated that the species found on Mt. Daeam is a new species that is more
closely related to P. middendoranus and P. takeshimensis than to the remaining four Phedimus species.
Here, we provided a full description of the new species P. daeamensis as well as an updated key for the
seven Phedimus species examined.
Keywords
Molecular diagnosis, new species, Phedimus, phylogeny
* ose authors contributed equally to this work.
Copyright Tae-Young Choi et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC
BY 4.0), which permits unrestricted use , distribution, and reproduction in any medium, provided the original author and source are credited.
PhytoKeys 212: 57–71 (2022)
doi: 10.3897/phytokeys.212.82604
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Tae-Young Choi et al. / PhytoKeys 212: 57–71 (2022)
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Introduction
Until ‘t Hart (1995) resurrected the genus Phedimus Ranesque (Ranesque 1817)
by separating it from Sedum, the taxonomic group had been buried for approximately
over a century. Since its resurrection, ca. 20 species have been added to Phedimus (Fu
et al. 2001; ‘t Hart and Bleij 2003). Most taxa in the genus are distributed throughout
Eurasia; their primary habitats are rocky slopes and grasslands (Fu et al. 2001). It is now
widely accepted that the two genera, Phedimus and Sedum, are primarily distinguished
by their leaf and testa shapes, which is further supported by several molecular studies
(Ohba et al. 2000; Mayuzumi and Ohba 2004; Gontcharova et al. 2006; Gontcharova
and Gontcharov 2009). Phedimus, a perennial herb, is divided into two subgenera
(Phedimus and Aizoon) that dier in petal colors, sterile stems, and testa structures. In
East Asia, approximately 15 taxa are recognized based on the aforementioned morpho-
logical traits, with more emphasis on the number of stems and phyllotaxis (Borisova
1939; Fu et al. 2001; Ohba 2001). However, in many cases, the delimitation of taxa is
challenging because of the extensive morphological variations (Mayuzumi and Ohba
2004; Moon and Jang 2020) within the genus. Furthermore, the wide use of Phedimus
as a core source of horticultural cultivars complicates the taxonomic issues (Stephen-
son and Harris 1991; Han et al. 2020). Given the taxonomic challenges, reporting a
new species only by morphological features (e.g., Chao 2020) may need an additional
molecular examination.
ere are eight Phedimus species including two endemic species and one with
two infraspecic taxa in Korea [Phedimus aizoon (L.) ‘t Hart var. aizoon, P. aizo-
on (L.) ‘t Hart var. latifolius (Maxim.) H. Ohba, P. kamtschaticus (Fisch. & C.A.
Mey.) ‘t Hart, P. latiovalifolius (Y.N. Lee) D.C. Son & H.J. Kim, P. middendoranus
(Maxim.) ‘t Hart, P. selskianus (Regel & Maack) ‘t Hart, P. takesimensis (Nakai) ‘t
Hart, P. zokuriensis (Nakai) ‘t Hart] (Park 2007; Korea National Arboretum 2021).
According to Lee et al. (2003), all Korean species belong to the subgenus Aizoon.
However, some species show considerable intraspecic morphological variation lead-
ing to taxonomic confusion, particularly where identity and species boundaries are
concerned (Ryu et al. 2011; Moon and Jang 2020). Phedimus kamtschaticus (Fisch.)
‘t Hart is a compelling example of the marked infraspecic morphological variation
(e.g., wide variety of leaf shapes) (Park 2007; Moon and Jang 2020). In fact, dur-
ing a 2019 study of specimens at the herbarium of the Korea National Arboretum
(KH), multiple sheets collected on Mt. Daeam and Gangwon province diered sub-
stantially from the rest of the collection. Specimens with unique morphotypes were
identied as P. kamtschaticus or P. middendoranus (Maxim.) t’ Hart. (Oh 1985;
Oh et al. 2015). Of those, the Mt. Daeam specimens were identied as P. sikokianus
(Chung and Kim 1989); however, the distribution of this species is restricted to
high mountain areas in Japan, suggesting that the Mt. Daeam specimens were likely
misidentied. Accordingly, a close investigation of the Phedimus plants collected on
Mt. Daeam was carried out.
Phedimus daeamensis, a new species found in Korea 59
Mt. Daeam, is a high-altitude mountain (> 1300 m) in Korea, which owing to
its diverse geographical and environmental characteristics is an area of substantial
biodiversity (Ministry of Environment 2007). e primary soil components of Mt.
Daeam are granite and gneiss followed by sand (~11%), silt, and clay (~10%; Minis-
try of Environment 2007). Notably, Korea’s only reported peatland (Min et al. 2000;
Kim et al. 2005), Yongneup, which consists of ve swamps, is located in high altitudes
(1000–1200 m) of the mountain. e climate is typically temperate with cold and
humid conditions (average annual temperature = ~10 °C and average annual relative
humidity = 71%; Ministry of Environment 2007), thus serving as a refuge for several
northern plants (Min et al. 2000; Kim et al. 2005). Over 300 taxa, including 20 Ko-
rean endemics, have been recorded on Mt. Daeam, and ca. 70 are protected by Korean
law (Ministry of Environment 2007). e unique environmental properties of Mt.
Daeam may have contributed to high species richness as discoveries of new plant taxa
are ongoing (Lee et al. 2013; Gil et al. 2019).
In the present study, we report a new plant species, P. daeamensis T.Y. Choi &
D.C. Son of the genus Phedimus subgenus Aizoon. We described the morphological
characters and habitat features of the new species with a detailed botanical illustration
in gray-scale hand drawing. To delimit the species boundary from the six closest related
taxa, we performed morphological observations as well as a molecular phylogenetic
study. A key to the Korean species of Phedimus (subgenus Aizoon) including the new
species was established based on the examined morphological characters.
Materials and methods
Morphological examination
We collected four living samples of P. daeamensis and prepared a voucher specimen.
Referring to the relevant protologues, oras, and monographs (Fu et al. 2001; Ohba
2001; Lee et al. 2003; Park 2007), we determined six target congeneric taxa for ex-
amination. All samples used for the study were collected legally. To compare the mor-
phological characteristics of the new species with the six most closely related conge-
ners, we borrowed ca. 100 herbarium specimens deposited in the KH and the Makino
Herbarium (Suppl. material 1: Table S1). Using an Olympus dissecting stereo micro-
scope (SZX16), morphological observations were made on all parts of the plants with
a particular focus on the shape of leaves and leaf parts as well as the features of the
reproductive organs. Microscopic oral parts such as the carpels and stamens were dis-
sected when required. Five characters associated with the leaf (the phyllotaxis, length
and width of the leaves, shape of the petioles, and the blades), and several associated
with the ower (including size and shape of the calyx lobes, number and shape of the
petals, and numbers of stamen and carpel; Table 1 and Suppl. material 1: Table S2;
Fig. 1) were assessed.
Tae-Young Choi et al. / PhytoKeys 212: 57–71 (2022)
60
Molecular diagnosis
To delimit the new species from the six most closely related taxa we examined their
phylogeny. Sixteen samples of the seven taxa (three P. daeamensis and remaining
of the six closely relatives) were collected from 14 localities across South Korea
and Japan (see Suppl. material 1: Table S3). ree samples of the new species were
included to determine the species’ monophyly. We rst examined the three regions
of cpDNA (atpF-atpH IGS, trnL-trnF IGS, and psbA-trnH IGS) and the nrITS
region discovered by Mayuzumi and Ohba (2004) in test samples from all seven
taxa. After the DNA polymorphism test, we excluded the atpF-atpH and trnL-trnF
IGS regions because of the lack of polymorphism among the seven taxa. Genomic
DNAs of the 16 samples were extracted from either fresh or dried leaf samples
using DNeasy plant mini kit (Qiagen, Hilden, Germany) following the manufac-
turer’s protocol. e PCR amplications were carried out using GeneAmp PCR
system 9700 with a total reaction volume of 50 uL containing 50 ng of template
DNA. e amplication conditions are provided in Suppl. material 1: Table S4.
After a series of purication steps performed by Macrogen (Seoul, Korea), the PCR
products were sequenced on an ABI Prism 3730XL genetic analyzer (Applied Bio-
systems, Waltham, USA) using ABI Prism BigDye terminator v 3.1 cycle sequenc-
ing kit (Applied Biosystems, Waltham, USA) at the Macrogen facility (Macrogen,
Seoul, Korea).
We also included seven accessions of three Phedimus taxa (P. latiovalifolius, P.
aizoon var. oribundus, P. takesimensis) downloaded from GenBank to test the spe-
cies boundaries across all Phedimus taxa co-occurring in Korea and Japan (Suppl.
material 1: Table S5). We assigned two Rhodiola species (Rhodiola brevipetiolata and
R. alsia) to the out-group based on previous phylogenetic research (Mayuzumi and
Ohba 2004). All sequences were edited and aligned using Geneious Aligner in Ge-
neious Prime ver. 2020.0.5, whereas other parameters were set as defaults. We then
manually adjusted the aligned sequences. All DNA sequences obtained from the
study were deposited in GenBank (accession numbers in Suppl. material 1: Table
S3). We inferred phylogeny for the nrITS and cpDNA regions independently. Data
concatenation was not considered because previous studies on Phedimus phylogeny
showed substantial incongruence between nrITS and cpDNA trees (Seo et al. 2020).
e phylogenetic trees were instead inferred from maximum likelihood (ML) and
Bayesian interference (BI) methods. ML analyses were performed using RAxML
plugin v4.0 implemented in Geneious Prime with the GTR CAT approximation
(Lartillot and Philippe 2004). Node supports were evaluated with 1000 bootstrap
replicates (Felsenstein 1985). BI analyses were performed in MrBayes 3.2.6 (Ron-
quist and Huelsenbeck 2003) using four chains (three heated and one cold) for 5
million generations while sampling every 1000th generation. e rst 25% of the
samples were discarded as a burn-in, and the remaining trees were used to produce a
50% majority-rule consensus tree.
Phedimus daeamensis, a new species found in Korea 61
Results
Morphological examination
We used the plant habit, leaf shapes, and margins to distinguish the newly described
Phedimus species (Fu et al. 2001; Ohba 2001; Lee et al. 2003; Park 2007). Phedimus
aizoon, P. kamtschaticus, and P. takesimensis were easily distinguished from the ve re-
maining species by height (> 20 cm) and leaf margin (entirely toothed; Table 1). Phedi-
mus daeamensis was morphologically most similar to P. middendoranus and P. sikoki-
anus in terms of the following characters: brous roots, not robust, and stems shorter
than 20 cm, somewhat prostrate (Table 1). However, P. daeamensis was distinguished
from P. middendoranus by its leaf shape (P. daeamensis leaf shape-obovate, 1–2.3 cm
long; leaf margins with 4–5 teeth from apex to mid; sepals (calyx lobes) lanceolate) and
from P. sikokianus by its leaf phyllotaxis and seed shape (Fig. 1 and Table 1).
Table 1. Summary of diagnostic characters observed in Phedimus daeamensis and the two morphologi-
cally closest taxa. e full diagnostic morphological characters of all seven Phedimus taxa investigated in
the study are presented as supplementary information (Suppl. material 1: Table S2).
P. middendoranus P. sikokianus P. daeamensis
Leaves alternate opposite alternate
• blade shape linear-spatulate widely oblanceolate to obovate obovate
• blade size 1.2–4 cm long, 0.2–0.5 cm wide 0.8–2.3 cm long, 0.6–1.3 cm wide 1–2.3 cm long, 0.5–1.2 cm wide
• margins margin apically serrate 2–3,
apex obtuse
margin apically to mid crenate
2–4, apex rounded
margin apically to mid serrate
4–5, apex obtuse
Calyx lobes 5, linear, 2–3 mm long, apex
obtuse
5, lanceolate, 2–3 mm long, apex
obtuse
5, lanceolate, 3–4 mm long, apex
obtuse
Seeds obovoid ellipsoid, ca. 0.8–1 mm long obovoid, ca. 0.7–1 mm long
Taxonomic treatment
Phedimus daeamensis T.Y. Choi & D.C. Son, sp. nov.
urn:lsid:ipni.org:names:77307628-1
Fig. 1
Type. R K. Gangwon-do, Inje-gun, Buk-myeon, Wolhak-ri, Mt. Dae-
am. Elevation 1,000 m. 20 August 2014. K.H. Lee & S.K. So 0001 (holotype KH;
isotypes 2 sheet, KH).
Perennial herbs. Rhizome woody, elongated. Roots not tuberous; rootstock not
robust. Stems numerous, more basally branched, tufted, creeping, ascending, 12–
21cm long, glabrous. Leaves alternate, sessile, coarsely arranged; leaf blade obovate,
1–2.3 cm long, 0.5–1.2 cm wide, at, base narrowly cuneate, margin apically to mid
serrate 4–5×, entire at base, apex obtuse; lower leaves almost all entire. Inorescence
Tae-Young Choi et al. / PhytoKeys 212: 57–71 (2022)
62
corymbiform-cymose, many-owered; bracts leaf-like. Flowers bisexual, mostly 5-mer-
ous, shortly pedicelled. Calyx tube 2.1–3.2 mm long; lobes spurless, lanceolate, 1–1.2
mm long, apex obtuse. Petals free, yellow, lanceolate to oblong, 5–6.5 mm long, abaxi-
ally keeled, apex acuminate, spreading at anthesis. Stamens 10, in 2 series, erect, short-
er than petals, those opposite to petals adnate to them to 1/4 of length from the base;
anthers red, ellipsoid, ca. 1 mm long; laments yellow. Pistils 4.5–5 mm long; ovaries
ca. 2.5 mm long, connate at the base; styles slender, 2–3 mm long. Carpels 5, erect,
equaling or slightly shorter than the petals, adaxially gibbous, shortly connate at the
base. Follicles greenish, stellately and horizontally spreading, ca. 4 mm long, with a
very short beak. Seeds 0.8–0.9 mm long, brown, obovoid, scalariform, ribbed, striate.
Flowers in May to June, fruiting in July to August.
Distribution and habitat. Republic of Korea (Prov. Gangwon). Stony clis and
rock crevices, at ca. 1000 m.
Etymology. e specic epithet, “daeamensis”, is based on the name of the loca-
tion, Mt. Daeam, where Phedimus daeamensis was discovered.
Korean name. Dae-am-gi-rin-cho.
Molecular diagnosis. In total, 32 sequences of two DNA regions (ITS and psbA-
trnH IGS) were newly obtained from the 16 accessions of P. daeamensis and the six
most closely related taxa (Suppl. material 1: Table S3). We also used 15 sequences from
eight accessions obtained from GenBank (P. aizoon var. oribundus, P. latiovalifolius, P.
takesimense) for the phylogenetic analysis. e lengths of the ITS and psbA-trnH IGS
alignment were 588 and 272 base pairs, respectively (Table 2). After an alignment of
24 accessions, we found 173 variable sites and 144 of these were parsimony informative
(Table 2 and Suppl. material 1: Table S6). Overall, the GC ratio was 50.5% and 22.5%
for ITS and psbA-trnH IGS, respectively (Table 2). K2P genetic distances among in-
group individuals ranged from 0 to 0.043 (mean 0.023) for ITS and 0 to 0.048 (mean
0.018) for psbA-trnH IGS (Table 2). We also found a 6 bp inversion in the psbA-trnH
IGS of all P. daeamensis accessions and one accession of P. takesimensis (Suppl. material
1: Table S6). We excluded this inversion from further phylogenetic analysis.
Overall, the inferred phylogenies from the two regions dier, particularly in the
basal nodes (Figs 2, 3). ere was a congruence between the ML and BI trees inferred
from the ITS and psbA-trnH IGS data sets (Figs 2, 3, Suppl. materials 2, 3: Figs S1, S2;
posterior probabilities are indicated in ML trees). In the psbA-trnH IGS trees, P. daea-
mensis was separated but formed an unresolved polytomy (Fig. 3 and Suppl. material 3:
Fig. S2). Phedimus sikokianus formed a monophyletic group, whereas all other species
showed more complicated and mixed clustering patterns (Fig. 3 and Suppl. material 3:
Fig. S2). In the ITS trees, two major clades were recognized, but only clade 1 was statisti-
cally robust (Fig. 2 and Suppl. material 2: Fig. S1). e three samples of the putative new
species, P. daeamensis, formed a well-supported monophyletic clade (bootstrap value; BS
= 95%; posterior priority; PP = 0.99) that was separated from the other species. Phedi-
mus daeamensis again formed a clade together with P. middendoranus (one sample)
and P. takesimensis (three samples), but the statistical support was very weak (Fig. 2 and
Suppl. material 2: Fig. S1). All accessions of P. sikokianus formed a well-supported clade
Phedimus daeamensis, a new species found in Korea 63
Figure 1. Phedimus daeamensis A habit B leaf C ower D petal and stamen E carpel F seed. (Illustrated
by Kyungsoo Eo).
Tae-Young Choi et al. / PhytoKeys 212: 57–71 (2022)
64
(BS = 95.9%; PP = 0.99) with samples of P. kamtschaticus and P. aizoon, both of which
were not monophyletic (Fig. 2, Suppl. material 2: Fig. S1). Phedimus latiovalifolius was
nested within a clade containing samples of P. kamtschaticum and P. aizoon (Fig. 2).
Table 2. Results of the cpDNA data sets used in this study. e out-group taxa were included in the
analyses, except for the K2P distance.
ITS psbA-trnH IGS
Sequence length (bp) 572–579 234–266
Aligned length (bp) 588 272
Mean G+C ratio (%) 50.5 22.5
No. of variable characters 144 29
No. of parsimony informative characters (%) 120 (85.7) 24 (82.8)
K2P distance (mean)*0–0.043 (0.023) 0–0.048 (0.018)
* Out-group taxa excluded.
Key to Phedimus daeamensis and related species
1 Stems 1–3, erect; leaves lanceolate, apex acuminate ...........Phedimus aizoon
– Stems many, ascending to prostrate; leaves spathulate, obovate, oblanceolate
or elliptic-oblanceolate, apex obtuse to rounded .........................................2
2 Roots thick, robust; stems 20–50 cm long, ascending ................................. 3
– Roots brous; stems less than 20 cm long, prostrate ...................................4
3 Leaves oblanceolate or spathulate, margins serrate in upper half ....................
................................................................................ Phedimus takesimensis
– Leaves spathulate, obovate or elliptic, margins entire or with few acute to
obtuse teeth .......................................................... Phedimus kamtschaticus
4 Leaves broadly ovate, margins irregularly dentate ... Phedimus latiovalifolius
– Leaves obovate to linear, margins serrate or crenate ..................................... 5
5 Leaves obovate, somewhat concave .............................................................6
– Leaves linear-spathulate or elliptic-oblanceolate, at ...................................7
6 Leaves opposite, margins crenate, seeds ellipsoid .........Phedimus sikokianus
– Leaves alternate, margins serrate, seeds obovoid .........Phedimus daeamensis
7 Stems prostrate; leaves 1.2–2.5 cm × 3–5 mm, with 2 or 3 teeth...................
....................................................................... Phedimus middendoranus
– Stems decumbent; leaves 2.5–3.5 cm × 1.1–1.6 cm, with many teeth ...........
..................................................................................Phedimus zokuriensis
Discussion
Phedimus has been a rather unexplored taxonomic group until the resurrection of the
genus by ‘t Hart (1995). Since then, the genus has attracted substantial attention be-
cause of its frequent use in horticultural practices (Han et al. 2020). However, Phedimus
is dicult to categorize taxonomically because of complex morphological variations,
Phedimus daeamensis, a new species found in Korea 65
potential hybridization, and introgression among congeneric taxa (Yoo and Park 2016;
Han et al. 2020). e possibility of polyploidy (including aneuploidy in Phedimus)
was also suggested by several empirical studies (Baldwin 1943; Uhl and Moran 1972;
Amano 1990; Amano and Ohba 1992; Chung et al. 2020). Accordingly, taxon de-
limitation in the genus Phedimus based solely on morphological characters can easily
be misleading and inconclusive, particularly in the early developmental stages when
there are no well-developed reproductive organs present. With the recent advancement
of molecular tools, molecular markers have helped overcome many of the limitations
Figure 2. Maximum likelihood tree for individuals of Phedimus daeamensis and related taxa based on
nrITS. Numbers above branches indicate bootstrap values (> 50%) and posterior probabilities (> 0.5).
Tae-Young Choi et al. / PhytoKeys 212: 57–71 (2022)
66
associated with species delimitation (Pelser et al. 2017; Perkins 2019). Coupled with
morphological examinations, our molecular analysis found that P. daeamensis is well-
separated from the P. kamtschaticus complex and P. sikokianus, although the taxa were
nearly indistinguishable by morphological characters in the early developmental stages.
Overall, our study characterized the morphological distinctiveness of the new-
ly described species (P. daeamensis) from the six closest related congeners. How-
ever, most characters of examination were vegetative and thus showed signicant
Figure 3. Maximum likelihood tree for individuals of Phedimus daeamensis and related taxa based on psbA-
trnH IGS. Numbers above branches indicate bootstrap values (> 50%) and posterior probabilities (> 0.5).
Phedimus daeamensis, a new species found in Korea 67
infraspecic variation across varying environments. Phedimus kamtschaticus and P.
aizoon showed substantial morphological variation. Although P. kamtschaticus, the
most commonly occurring Phedimus species in Korea (Korea National Arboretum
2016), can easily be distinguished from the newly described species (P. daeamensis)
when the plants are fully mature, the identication may not be as straightforward
in the early stage of the development. Our results highlighted a key morphological
feature dierentiating P. daeamensis from P. kamtschaticus; however, extreme care
must be taken with juvenile plants. Phedimus daeamensis was initially recognized as
P. sikokianus by Chung and Kim (1989) because of its morphological anities. Ac-
cording to our results, the putative new species diers from P. sikokianus by the type
of phyllotaxis and the seed shape, but infraspecic variations in those characters
should be considered. e leaf shape of P. middendoranus was prominently linear,
which diers substantially from the remaining congeners; however, a very limited
number of specimens were examined in our study (Suppl. material 1: Table S1). e
morphological analyses we performed provided several key characters distinguish-
ing P. daeamensis from the remaining six Phedimus taxa, however, some taxa, e.g., P.
middendoranus and P. sikokianus, only had a limited number of sheets. erefore,
we further employed a molecular phylogenetic approach to support the morpho-
logical results.
Notably, phylogenetic trees reconstructed based on the ITS and psbA-trnH IGS
regions were consistent with the morphological results. In both ML trees from nrITS
and cpDNA, the three morphotypes sharing the same morphological characters as the
newly reported P. daeamensis came out as a monophyletic group or as an unresolved
polytomy. Phedimus daeamensis was always placed separate from both P. kamtschaticus
and P. sikokianus, but the phylogenetic relationship of the species with its closest re-
lated taxa was inconclusive because of low clade support and inconsistency between
nrITS and cpDNA trees. In the ITS trees, P. daeamensis fell into the same clade as P.
takesimensis and P. middendoranus (Fig. 2), whereas in the psbA-trnH IGS trees, P.
daeamensis was “sister” to all other species except for P. sikokianus (Fig. 3). Although the
phylogenetic relationship among P. daeamensis, P takesimensis, and P. middendoranus
was rather ambiguous, the taxa were relatively easy to distinguish based on morpho-
logical characters. Phedimus takesimensis was much larger (20–50 cm tall) and charac-
terized by thick roots, whereas P. middendoranus has linear leaves. Considering all the
evidence and consistent with our hypothesis, P. daeamensis is a species in its own right
and well-separated from the remaining six species.
Acknowledgements
is work was supported by the National Research Foundation of Korea (NRF) grant
funded by the Korea government(MSIT) (No. NRF-2021R1A6A3A01086610). We
thank Dr. Jungsim Lee and Kang Hyup Lee for providing valuable specimens and ma-
terials. We also thank Kyungsoo Eo for providing Fig. 1.
Tae-Young Choi et al. / PhytoKeys 212: 57–71 (2022)
68
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Supplementary material 1
Tables S1–S6
Authors: Tae-Young Choi, Dong Chan Son, Takashi Shiga, Soo-Rang Lee
Data type: occurence, morphology (docx./xslx. les in zip. archive)
Explanation note: Table S1. List of examined specimens for morphological study.
Table S2. Diagnostic characters observed in Phedimus daeamensis and the six clos-
est related taxa. Table S3. Voucher information and GenBank accession numbers
for the 16 accessions of P. daeamensis and closely related taxa examined in this study.
Table S4. PCR/sequencing primers and PCR cycling conditions for the DNA re-
gions examined in this study. Table S5. Voucher information and GenBank acces-
sion numbers for 10 Phedimus accessions downloaded from GenBank. Table S6.
Variable sites obtained from the ITS and psbA-trnH IGS regions.
Copyright notice: is dataset is made available under the Open Database License
(http://opendatacommons.org/licenses/odbl/1.0/). e Open Database License
(ODbL) is a license agreement intended to allow users to freely share, modify, and
use this Dataset while maintaining this same freedom for others, provided that the
original source and author(s) are credited.
Link: https://doi.org/10.3897/phytokeys.212.82604.suppl1
Phedimus daeamensis, a new species found in Korea 71
Supplementary material 2
Figure S1
Authors: Tae-Young Choi, Dong Chan Son, Takashi Shiga, Soo-Rang Lee
Data type: Image (Adobe PDF le)
Explanation note: Figure S1. Bayesian inference tree for individuals of P. daeamensis
and related taxa based on ITS. Numbers above branches are posterior probabilities.
Copyright notice: is dataset is made available under the Open Database License
(http://opendatacommons.org/licenses/odbl/1.0/). e Open Database License
(ODbL) is a license agreement intended to allow users to freely share, modify, and
use this Dataset while maintaining this same freedom for others, provided that the
original source and author(s) are credited.
Link: https://doi.org/10.3897/phytokeys.212.82604.suppl2
Supplementary material 3
Figure S2
Authors: Tae-Young Choi, Dong Chan Son, Takashi Shiga, Soo-Rang Lee
Data type: Image (Adobe PDF le)
Explanation note: Figure S2. Bayesian inference tree for individuals of P. daeamensis
and related taxa based on psbA-trnH IGS. Numbers above branches are posterior
probabilities.
Copyright notice: is dataset is made available under the Open Database License
(http://opendatacommons.org/licenses/odbl/1.0/). e Open Database License
(ODbL) is a license agreement intended to allow users to freely share, modify, and
use this Dataset while maintaining this same freedom for others, provided that the
original source and author(s) are credited.
Link: https://doi.org/10.3897/phytokeys.212.82604.suppl3
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