Content uploaded by Eugeny V Karasev
Author content
All content in this area was uploaded by Eugeny V Karasev
Content may be subject to copyright.
198
ISSN 0031-0301, Paleontological Journal, 2007, Vol. 41, No. 2, pp. 198–206. © Pleiades Publishing, Ltd., 2007.
Original Russian Text © E.V. Karasev, V.A. Krassilov, 2007, published in Paleontologicheskii Zhurnal, 2007, No. 2, pp. 80–86.
INTRODUCTION
The Late Permian Subangarian flora of the Russian
Platform and Cis-Urals is dominated by gymnosperms
with small scaly and large pinnate leaves, convention-
ally assigned to conifers and peltasperms. It was named
the Tatarina flora, emphasizing the abundance of leaf
remains of the
Pursongia–Tatarina
group (Gomankov
and Meyen, 1986). However, the systematics of Suban-
garian peltasperms is insufficiently developed. Their
phylogenetic relationships both with the older Euro-
pean callipterids and the younger
Lepidopteris–Scyto-
phyllum
group, which became common in the terminal
Permian and Triassic, are still unclear. Some so far
unexplained morphological peculiarities (e.g., the axial
scales of
Lepidopteris
) imply that the leaf of pel-
tasperms may be of phylloclade nature, and this may be
true for all pteridosperms. Meyen (1987) hypothesized
that peltasperms might have been related to some Per-
mian scale-leaved gymnosperms of coniferoid aspect.
The phylloclades found in the Sokovka locality are rel-
evant to these topical problems of the systematics and
evolutionary morphology of Permian gymnosperms.
MATERIAL AND METHODS
The Sokovka locality is situated on the northwestern
boundary of the town of Vyazniki (Vladimir Region),
in the gully between the town and the quarry opposite
the village of Sokovka. In 1841, an expedition led by
Murchison first found Permian ostracodes and bivalves
near the town of Vyazniki. In 1951, 1952, 1955, and
1956, expeditions of the Paleontological Institute of the
Academy of Sciences of the USSR led by V’yushkov
gathered a collection of fossil fishes, amphibians, and
reptiles. In 1999–2003, Sennikov, Golubev, and Bul-
anov rediscovered two localities named Bykovka and
Sokovka corresponding to the Vyazniki II locality of
Efremov and V’yushkov (1955), where plant macrofos-
sils, spores and pollen grains, and bivalves and ostra-
codes were recorded. In 2005, additional material was
collected by a paleoentomological group led by
D.E. Shcherbakov. Afonin (2005) and Naugolnykh
(2005) contributed to the study of the Vyazniki flora.
The Vyazniki fauna includes typical Late Tatarian
bivalves, conchostracans, and fishes. Insect, tetrapod,
and plant assemblages are transitional between the typ-
ical Permian and Triassic assemblages. The ostracode
assemblage is of the Triassic aspect with the presence
of some Permian elements (Golubev et al., 2005; Sen-
nikov and Golubev, 2005).
The plant remains are preserved as impressions with
compression fragments. The fragments of compres-
sions were removed from the rock and studied with a
CAMSCAN scanning electron microscope. In addition,
cleared compressions and macerated cuticles were
studied with MBS-10 and Axioplan 2 light micro-
scopes. Photographs were taken with a Nikon Coolpix
4500 digital camera.
The stomatal index (SI) was determined by the
equation E = I + SC; SI = [SD/(E + SD)]
×
100
, where
SD is the number of stomata per mm
2
; E is the number
of epidermal cells per mm
2
; I is the number of ordinary
epidermal cells per mm
2
; and SC is the number of guard
cells per mm
2
(Woodward, 1987).
Late Permian Phylloclades of the New Genus
Permophyllocladus
and Problems of the Evolutionary Morphology of Peltasperms
E. V. Karasev and V. A. Krassilov
Paleontological Institute, Russian Academy of Sciences, ul. Profsoyuznaya 123, Moscow, 117997 Russia
e-mail: vkras@paleo.ru
Received May 10, 2006
Abstract
—Phylloclades from the Upper Permian (Tatarian) deposits of the Sokovka locality, Vladimir Region,
showing gradational transformation of a planate scale-leaved shoot into a foliar organ, are assigned to the new
genus
Permophyllocladus
(Peltaspermales?). The phylloclades are distinctly dorsoventral: scaly leaves and
their rudiments are developed on the lower side and are only marked by suture lines on the cuticle of the oppo-
site side. In epidermal characteristics, the phylloclades are similar to the leaves of peltasperms from coeval
deposits. It is supposed that peltasperm leaves are of phylloclade origin and were formed by cohesion of units
of a coniferoid scale-leaved shoot that resembles shoots of the Mesozoic family Hirmerellaceae (Cheirolepidi-
aceae), which also tend to develop phylloclades.
DOI:
10.1134/S0031030107020104
Key words
: phylloclades, peltasperms, conifers, leaf origin, Permian, Russian Platform.
PALEONTOLOGICAL JOURNAL
Vol. 41
No. 2
2007
LATE PERMIAN PHYLLOCLADES OF THE NEW GENUS
PERMOPHYLLOCLADUS
199
MATERIAL
The present study used material collected by
S.A. Afonin (2004), D.E. Shcherbakov, and A.C. Bash-
kuev (2005); the most important specimens were pro-
vided by Shcherbakov. The collection no. 5139 is
housed in the Paleontological Institute of the Russian
Academy of Sciences (PIN).
SYSTEMATIC PALEOBOTANY
Order Peltaspermales?
Genus
Permophyllocladus
Karasev et Krassilov, gen. nov.
Etymology. From the Permian Period and the
genus
Phyllocladus
.
Type species.
P. polymorphus
sp. nov.
Diagnosis. Planate branching shoots of vari-
ously connate scale leaves, gradationally transformed
into imparipinnate phylloclades by extensive leaf cohe-
sion. Leaves typically distinct on lower (abaxial) side,
but reduced to coalescent leaf cushions or marked by
suture lines alone on the opposite (adaxial) side. Lateral
branches opposite or subopposite spreading at open
angle, decurrent, forming pinnae or lobed pinnules of
pinnate phylloclades. Ultimate units short elliptical or
obovate branchlets with transverse sutures of adherent
leaf pairs, distally leaflike, rounded or notched at the
apex, reduced to phylloclade pinnules. Phylloclades
strongly cutinized, amphistomatic, papillate. Stomata
scattered, more numerous abaxially, irregularly ori-
ented, monocyclic. Subsidiary cells, 4–7(6), radial,
with proximal papillae. Florin ring distinct. Guard cells
small, sunken.
Species composition. Type species.
Comparison and remarks. In gymno-
sperms, phylloclades are known in the modern families
Cupressaceae, Phyllocladaceae, and Sciadopityaceae
and in the Mesozoic Hirmerellaceae (= Hirmerelli-
aceae, Cheirolepidiaceae). Among the latter, there are
forms with dorsoventral shoots in which a facial leaf is
only developed on one side (Watson, 1988). A pinnate
phylloclade formed from a flattened scale-leaved shoot
is described in detail in the Cretaceous genus
Androvet-
tia
Hollick et Jeffrey, which belongs either to the
Cupressaceae or Cheirolepidiaceae (Hueber and Wat-
son, 1988). Although a certain general resemblance to
Permophyllocladus
gen. nov. exists, significant dissim-
ilarities are observed, related to different directions of
phylloclade morphogenesis. In the Permian genus, the
maximal coalescence of leaves is observed in ultimate
branches of limited growth, terminating with an
imparipinnate foliar apex, whereas in
Androvettia
the
terminal branchlets and the apices of the penultimate
branches often retain the alternate arrangement of
leaves and look like shoots of unlimited growth. The
modern genus
Phyllocladus
L.C. et A. Rich apparently
combines both modes of phylloclade formation: with
branches of limited and unlimited growth (Hueber and
Watson, 1988).
In Permian gymnosperms, phylloclades have not
been found (or recognized) up to now. The most leaflike
variants of polymorphic phylloclades of the new genus
are similar to pinnate leaves of peltasperms having
entire or lobed alethopteroid pinnules. Permian leaves
of this type were traditionally referred to as
Callipteris
Brongniart; however, this generic name was found to be
preoccupied and has so far not been conserved in accor-
dance with the rules of botanical nomenclature.
A recent approach to the taxonomy of Permian pel-
tasperms permits generic names for reproductive
organs (
Autunia
F. Krasser,
Peltaspermum
T. Harris,
and
Autuniopsis
Poort et Kerp) being applied to associ-
ated leaves (
“Callipteris”, Lepidopteris
Schimper, and
Meyenopteris
Poort et Kerp, respectively), considered
in such cases as belonging to a natural genus. However,
we do not support this approach in the present paper,
since genera based on both reproductive organs and
leaves belong to morphotaxa of various degrees of nat-
uralness and are recognized by their morphological
characters rather than by their supposed taxonomic
affinities.
Axial scales or swellings of uncertain morphologi-
cal nature were recorded in the Triassic
Lepidopteris
and
Meyenopteris
, which have bipinnate leaves with
interstitial pinnules (Harris, 1932; Poort and Kerp,
1990). Comparison with the new genus
Permophyllo-
cladus
suggests that these structures are rudiments of
the scaly leaves of the initial phylloclade. In this con-
text, the callipteroid Permian leaves of
Lepidopteris
(“Peltaspermum”) martinsii
(Germar) Poort et Kerp,
which were described as bi- or tripinnate, with a forked
rachis, are of particular interest. Pinnules are aletho-
pteroid, subopposite or alternate, decurrent, finely
toothed in the upper part of the leaf. Venation is pinnate,
the midvein is relatively thin (or indistinct) and decur-
rent; lateral veins are rare, loosely arranged, simple or
forked. This species is characterized by highly poly-
morphic leaves, some of which have well-defined “blis-
ters” on rachises of the first and second orders (Poort
and Kerp, 1990). The possible phylloclade interpreta-
tion was not considered in the original description.
Unlike
Permophyllocladus
, scales are lost from the
ultimate segments, and the dorsoventral orientation is
expressed only in the thickness of the cuticle and the
density of stomata.
Naugolnykh (2005) described, from the “Bykovka”
locality near the town of Vyazniki, leaves of cf.
Lepi-
dopteris
(al.
Callipteris
)
martinsii
Townrow, which are
devoid of axial scales, and have triangular basal pin-
nules that become longer toward the acute apex. There-
fore, the material from the Bykovka locality is signifi-
cantly different from
Permophyllocladus polymorphus
sp. nov., although the cuticular characters are largely
identical.
200
PALEONTOLOGICAL JOURNAL
Vol. 41
No. 2
2007
KARASEV, KRASSILOV
6 84
1000
µ
m 1000
µ
m
1000
µ
m
1000
µ
m
1000
µ
m1000
µ
m
1000
µ
m 1000
µ
m
Plate 10
1 2 3
5 7
PALEONTOLOGICAL JOURNAL
Vol. 41
No. 2
2007
LATE PERMIAN PHYLLOCLADES OF THE NEW GENUS
PERMOPHYLLOCLADUS
201
Permophyllocladus polymorphus
Karasev et Krassilov, sp. nov.
Plate 10, figs. 1–8; Plate 11, figs. 1–6
Etymology. From the Greek
polymorphus
(of variable shape).
Holotype. PIN, no. 5139/1, Vladimir Region,
Vyazniki district, right bank of the Klyaz’ma River,
gully between the town of Vyazniki and Bykovskii
quarry, Sokovka locality, Upper Permian, Tatarian
(Pl. 10, figs. 4–6; Pl. 11, figs. 1, 2; Figs. 1, 2b, 2c).
Diagnosis. As for the genus.
Description (Figs. 1–4). The phylloclade con-
sists of a planate axis 4–4.5 mm wide and lateral
branches. The most complete specimen is a shoot
50 mm long (Pl. 10, fig. 4). The axis is covered with
scaly leaves that partially belong to the decurrent bases
of lateral branches. Leaves supporting the lateral
branches are relatively large, variously connate, ellipti-
cal, 1.4–1.6 mm wide, alternate, the step of the spiral is
about 1 mm.
The compression shows a dorsoventrally differenti-
ated shoot: the supposed lower (abaxial) side has more
or less distinct leaves and a higher stomatal index,
whereas the opposite (upper, adaxial) side is more flat-
tened, and the leaves are no longer distinct.
Lateral branches are placed 5–7 mm apart on the
main axis of the shoot, at an angle about 90
°
. They are
subopposite, flattened-cylindrical, apically rounded,
straight or reflexed, about 12 mm long and 2–3 mm
wide in the middle of the shoot, rapidly tapering toward
the apex. The leaves are obovate, decurrent, and vari-
ously fused and reduced. The cohesion of the leaves
increases from the base of the branch toward the apex
and is more complete on the flattened adaxial side. The
abaxial leaves are fused in pairs basally (Pl. 10, fig. 6,
Fig. 1a) or along their entire length; they form a facial
row of slightly convex, transversely elongated leaf
cushions of elliptical, trapezoidal, or polygonal out-
lines, 1.5 mm wide, giving the branch an articulate
aspect (Pl. 10, fig. 8). On the flattened side, these vari-
ants are matched by transverse leaf cushions (Fig. 1b)
or transverse sutures that in the extreme case are distin-
guishable only on the cuticle (Pl. 10, figs. 5, 7).
The branchlets of the last order are axillary, adnate
to their supporting leaves, mostly reduced to rounded-
elliptical or subspherical lobes that may appear as lat-
eral scaly leaves, the opposite leaves of the lateral pairs
being directly fused with each other (connected by a
concave suture) on the flattened foliar side of the shoot
(Fig. 1c).
The phylloclades are amphistomatic, the cuticle is
thick (6–8
µ
m), resistant to maceration. The cuticles of
the lower and upper epidermises are of approximately
equal thickness (Fig. 2a). The ordinary epidermal cells
are pentagonal to heptagonal, with straight, smooth
anticlinal walls, 15–30
µ
m across (Pl. 11, fig. 1). In the
basal region of the leaf, they become slightly larger, and
the degree of cutinization decreases. The periclinal wall
bears a median papilla that is basally 7–8
µ
m in diame-
ter and up to 3
µ
m high. The largest papillae are situated
in the marginal regions of the leaf; in the central part,
papillae are sometimes lacking (Pl. 11, figs. 3, 5). The
densities of stomata are different on the opposite leaf
surfaces: on the side with more distinct leaf scales (the
Explanation of Plate 10
Figs. 1–8.
Permophyllocladus polymorphus
gen. et sp. nov.: (1) paratype PIN, no. 5139/4, abaxial side of the apical region of a
flattened dorsoventral scale-leaved shoot; (2) the same, adaxial side; (3) paratype PIN, no. 5139/3, abaxial side of a shoot with two
lateral branchlets; (4) holotype PIN, no. 5139/1, compression of the middle portion of a phylloclade with lateral branchlets; (5) holo-
type PIN, no. 5139/1, adaxial side of a lateral branchlet; (6) holotype PIN, no. 5139/1, abaxial side; (7) paratype PIN, no. 5139/2,
adaxial side of the compression of a lateral branchlet with two rows of scales on the rachis; (8) the same, abaxial side; (1, 2, 6) SEM;
(3, 5) LM.
Ä
B
III
II
I
3
2
1
1
2
3
Ä
(a) (b)
B
3
2
1
I
II
III
ÄÄ
3
2
11
2
3
(c)
BB
Fig. 1.
Permophyllocladus polymorphus
gen. et sp. nov., holotype PIN, no. 5139/1: (a) abaxial side of a lateral branchlet; (b) abaxial
side of a lateral branchlet, schematic sections along the lines A–A and B–B; (c) adaxial side of a lateral branchlet; (I, II, III) facial
row of leaf cushions; (1, 2, 3) lateral lobes corresponding to reduced terminal branchlets with fused leaves. Scale bar 500
µ
m.
202
PALEONTOLOGICAL JOURNAL
Vol. 41
No. 2
2007
KARASEV, KRASSILOV
Plate 11
30
µ
m
1 2 10
µ
m
410
µ
m
30
µ
m
3
530
µ
m610
µ
m
PALEONTOLOGICAL JOURNAL
Vol. 41
No. 2
2007
LATE PERMIAN PHYLLOCLADES OF THE NEW GENUS
PERMOPHYLLOCLADUS
203
abaxial side) the stomata are twice as frequent as on the
other side (table), they are regularly arranged and do
not form rows. The stomatal apertures are irregularly
orientated.
Stomata are monocyclic, encyclocytic, or, less com-
monly, actinocytic. Usually, there are six subsidiary
cells, or, more rarely, four, five, or seven. They are radi-
ally arranged around the stoma, their distal walls form
a ring or an irregular contour 38–56
µ
m across. The
proximal walls are strongly cutinized, papillate, the
papillae are hollow, sometimes apically thickened, or,
more rarely, solid. The base of papilla is about 5–8
µ
m
in diameter, the height is up to 6
µ
m (Pl. 11, fig. 6). The
guard cells are sunken at a depth of 5–10
µ
m below the
leaf surface. They are 10–13
µ
m long, 3.8–5.5
µ
m wide
(Pl. 11, fig. 2, Figs. 2b, 2c).
There are phylloclades with the leaves that are only
basally connate on the penultimate axis, forming a wide
inversely wedge-shaped bilobed scale. In such speci-
Explanation of Plate 11
Figs. 1–6.
Permophyllocladus polymorphus
gen. et sp. nov., cuticle, SEM: (1, 2) holotype PIN, no. 5139/1; (1) lower cuticle of a
scaly process of a lateral branchlet; (2) encyclocytic stomatal apparatus; (3) paratype PIN, no. 5139/4, external surface of the cuticle
with distinct papillae on ordinary epidermal cells; (4) paratype PIN, no. 5139/7, stomatal apparatus of a leaflike branchlet;
(5) paratype PIN, no. 5139/3, external surface of the upper cuticle with occasional papillae on ordinary epidermal cells; (6) paratype
PIN, no. 5139/4, stomatal apparatus with large proximal papillae overhanging the stoma.
(a) 10
µ
m
10
µ
m
10
µ
m
(b) (c)
Fig. 2.
Permophyllocladus polymorphus
gen. et sp. nov.,
holotype PIN, no. 5139/1: (a) thickness of the lower cuticle,
SEM; (b) schematic reconstruction of stomatal apparatus;
(c) stomatal apparatus at an angle of 45
°
, SEM; (a, c)
Vladimir Region, vicinity of the town of Vyazniki, Sokovka
locality, Upper Permian, Tatarian.
(a) (b)
3III 3
22II
22
I1
3
2
1
2
3
(c) (d)
AA
AA
(e) (f)
Fig. 3.
Polymorphism of phylloclades of
Permophyllocla-
dus polymorphus
gen. et sp. nov.: (a, b) PIN, no. 5139/3,
phylloclade with two lateral branchlets; (c, d) paratype PIN,
no. 5139/4, apical region of a branch with pinnule-like ulti-
mate branchlets; (e, f) paratype PIN, no. 5139/7, apical
portion of a leaflike branchlet and schematic section along
the line A–A; (a, c, e) abaxial side; (b, d, f) adaxial side;
(1, 2, 3) pinnule-like lateral branchlets; (I, II, III) facial rows
of leaf cushions. Scale bar 500
µ
m.
204
PALEONTOLOGICAL JOURNAL
Vol. 41
No. 2
2007
KARASEV, KRASSILOV
300 µm
1000 µm 1000 µm
(a)
(f) (d) (e)
(c)
(b)
Fig. 4. Polymorphism of phylloclades of Permophyllocladus polymorphus gen. et sp. nov.: (a) paratype PIN, no. 5139/6, com-
pressed shoot with lobed pinnule-like lateral branchlets; (b) paratype PIN, no. 5139/5, compressed shoot with entire pinnule-like
lateral branchlets; (c) paratype PIN, no. 5139/6, adaxial side of a compressed pinnule-like branch; (d, e) paratype PIN, no. 5139/7,
two sides of a compressed apex of pinnule-like branchlets, SEM; (f) PIN, no. 5139/4, external side of lower cuticle, SEM;
(a−f) Vladimir Region, vicinity of the town of Vyazniki, Sokovka locality, Upper Permian, Tatarian; (c) LM; (d–f) SEM. Scale bar
(a–c) 1000 µm.
PALEONTOLOGICAL JOURNAL Vol. 41 No. 2 2007
LATE PERMIAN PHYLLOCLADES OF THE NEW GENUS PERMOPHYLLOCLADUS 205
mens, the terminal branchlets are better developed,
with distinct scaly leaves (Pl. 10, figs. 1–3). On the
abaxial side of the penultimate axis, facial leaves are
tear-shaped or obovate, 1.0–1.8 × 1.2–1.7 mm. On the
adaxial side, they are reduced to cuticular folds
(Figs. 3a, 3b). The branchlets of the ultimate order are
elongate or conical, up to 2 mm long, with one or two
pairs of proximal leaves and a subspherical leaflike
apex (Figs. 3c, 3d). The leaves are adnate, fused for
their entire length, separated by a transverse fold, or
else they have free triangular tips. The cohesion of
basal leaves of lateral branchlets with their subtending
leaf on the penultimate axis results in a large (0.7–1 mm
wide) irregular leaf cushion at the base of the branchlet.
Occasionally, the ordinary epidermal cells are smooth-
walled and without papillae (Pl. 11, fig. 5).
The most leaflike specimens (Figs. 3e, 3f, 4a–4e)
have elongate pinnae (modified lateral branches) with
two rows of contacting pinnules (modified ultimate
branchlets), abaxially fused, and with an apical pinnule.
The lateral pinnules are obovate, spatulate, or rhomboi-
dal, decurrent, usually measuring about 1.6 × 1.6 mm.
The apical pinnule, which is formed of completely
fused distal scaly leaves, is larger and rounded. Abaxi-
ally, it is divided by a median longitudinal fold, and
adaxially it is entire. Epidermal cells along the pinnule
margins are distinctly elongate, the stomata are larger,
the contour of subsidiary cells is 50–60 µm across, the
guard cells are longer, up to 20 µm (Pl. 11, fig. 4,
Fig. 4d). SI on the abaxial (divided) side is 3.46,
whereas on the adaxial (entire) side it is 2.72.
Material. Seven impressions of phylloclades
with preserved compressions, including four fragments
of the middle region with lateral branches and three
detached lateral branchlets.
DISCUSSION
The polymorphism of Permophyllocladus gen. nov.
allows the transitions to be traced from a scale-leaved
shoot with incipient dorsoventral differentiation to a
pinnate phylloclade having variously reduced scaly
leaves. The comparison with leaves of peltasperms
shows that some callipterids (e.g., Lepidopteris martin-
sii) also betray phylloclade characteristics, although
they are less distinct. Phyllocladization is even more
advanced in the foliar organs assigned to Lepidopteris
and Meyenopteris, which are usually considered as
fernlike foliage, typical of pteridosperms. Axial scales
or swellings recorded in such “leaves” have formerly
been interpreted as analogous to petiolar scales of ferns
or as glands. Our data support the hypothesis that they
are reduced leaves of an initial scale-leaved shoot.
Therefore, we have obtained evidence of the phyllo-
clade nature of the leaves of the dominant Permian
gymnosperms, peltasperms. While in Permophyllocla-
dus the initial shoot with scaly leaves has not yet lost its
morphological distinctness showing successive phases
of cohesion, dorsoventral differentiation, and leaflike
flattening, in more advanced forms traces of phyllo-
clade origin occur as the axial scales only or are alto-
gether lacking.
Peltasperms are usually assigned to pteridosperms,
a vast group of Late Paleozoic gymnosperms with large
planate or more or less fernlike leaves. However, the
difference between typical pteridosperms and pel-
tasperms is that in the former group the ovules develop
on the foliar organs, whereas in the latter group they are
in cones.
Our data show that Permian gymnosperms with
scale-leaved branching shoots (“conifers”), on the one
hand, and with large pinnate leaves (“pteridosperms”),
on the other, might have belonged to one natural plant
group; this is supported both by the presence of transi-
tional forms of phylloclades, described in this paper,
and by similarity in epidermal characters.
However, the phyllocladization processes might
have been differently orientated in peltasperms and
coniferoids. In the former group, fusion of the leaves
progresses from terminal branchlets towards branches
of lower orders; in the latter, this process was directed
oppositely, although a combination of both modes is
conceivable.
In terms of morphogenesis, the difference between
typical pteridosperms and cycads, which also contain
forms with compound fernlike leaves, is that in pteri-
dosperms the ovuliphores were comprised in phyllo-
cladization, which led to the development of seeds on
fernlike leaves, whereas in cycads only vegetative
shoots were influenced by phyllocladization, and ovuli-
phores were variously strobilized. On account of the
latter distinction, peltasperms are closer to cycads and
may be considered as a possible ancestral group of
Mesozoic cycadophytes.
ACKNOWLEDGMENTS
We are grateful to D.E. Shcherbakov (PIN) for pro-
viding the material.
When this paper was in press, Gomankov (2006)
established a new species, Lepidopteris archaica
Gomankov, including specimens from the Sokovka
locality. However, the holotype of L. archaica from the
Density of stomata and stomatal indices for different sides.
Lower surface denotes the lower surface of phylloclade, upper
surface denotes the upper surface of phylloclade. (SD) number
of stomata per mm2, (SI) stomatal index
No. Lower surface Upper surface
SD SI SD SI
1 103 3.62 75 2.47
3 70 3.46 44 2.72
5 113 4.44 38 1.82
206
PALEONTOLOGICAL JOURNAL Vol. 41 No. 2 2007
KARASEV, KRASSILOV
Fore-Urals has little in common with our species.
Moreover, we see no confirmation of a phyllodial
nature (developed from a petiole) of the leaf of Lepi-
dopteris; according to our data, this is a homologue of
the phylloclade rather than phyllode.
REFERENCES
1. S. A. Afonin, “Latest Permian Palynological Assem-
blage from Vyazniki, European Russia: Stratigraphic
and Palaeoecological Significance in Relation to the
Permo-Triassic Boundary,” in The Nonmarine Permian,
ed. by S. G. Lucas and K. E. Zeigler, New Mexico Mus.
Nat. Hist. Sci. Bull., No. 30, 5–8 (2005).
2. V. K. Golubev, A. G. Sennikov, and S. V. Naugolnykh,
“New Data on the Geology and Paleontology of Permian
Deposits in the Vicinity of the Town of Vyazniki
(Vladimir Region),” in Paleostrat-2005. Annual Meeting
of the Section of Paleontology of the Moscow Society of
Nature Explorers and the Moscow Division of the Pale-
ontological Society, Moscow, February 14–15, 2005
(Paleontological Inst. Ross. Akad. Nauk, Moscow,
2005), pp. 14–15.
3. A. V. Gomankov, “A New Species of the Genus Lepidop-
teris (Peltaspermaceae, Peltaspermales) from the Upper
Permian of the Russian Platform,” Botan. Zh. 91 (12),
1906–1914 (2006).
4. A. V. Gomankov and S. V. Meyen, Tatarinovo Flora
(Composition and Distribution in the Late Permian of
Eurasia) (Nauka, Moscow, 1986) [in Russian].
5. T. M. Harris, “The Fossil Flora of Scoresby Sound, East
Greenland, Pt. 3,” Medd. Grønl. 83, 1–114 (1932).
6. F. M. Hueber and J. Watson, “The Unusual Upper Creta-
ceous Conifer, Androvettia from Eastern U.S.A.,” Bot. J.
Linn. Soc. 98, 117–133 (1988).
7. S. V. Meyen, Fundamentals of Paleobotany (Chapman
and Hall, London–New York, 1987).
8. S. V. Naugolnykh, “Upper Permian Flora of Vyazniki
(European Part of Russia), Its Zechstein Appearance,
and the Nature of the Permo-Triassic Extinction,” in The
Nonmarine Permian, ed. by S. G. Lucas and K. E. Zei-
gler, New Mexico Mus. Nat. Hist. Sci. Bull., No. 30,
226–242 (2005).
9. R. J. Poort and J. H. F. Kerp, “Aspects of Permian Palae-
obotany and Palynology XI. On the Recognition of True
Peltasperms in the Upper Permian of Western and Cen-
tral Europe and a Reclassification of Species Formerly
Included in Peltaspermum Harris,” Rev. Palaeobot.
Palynol. 63, 197–225 (1990).
10. A. G. Sennikov and V. K. Golubev, “Unique Vyazniki
Biotic Complex of the Terminal Permian from the Cen-
tral Russia and the Global Ecological Crisis at the
Permo-Triassic Boundary,” in The Nonmarine Permian,
ed. by S. G. Lucas and K. E. Zeigler, New Mexico Mus.
Nat. Hist. Sci. Bull., No. 30, 302–304 (2005).
11. J. Watson, “Cheirolepidiaceae,” in Origin and Evolution
of Gymnosperms, Ed. by C. B. Beck (Columbia Univ.
Press, New York, 1988), pp. 382–447.
12. F. I. Woodward, “Stomatal Numbers are Sensitive to
Increases in CO Concentration from the Pre-industrial
Levels,” Nature 327, 617–618 (1987).
