Appendix S1:
Identification of Celtis fruit stones and Juniperus seeds
Identification of Celtis fruit stones was based upon Matsutani (1987) supplemented by thorough
examinations of herbarium specimens at Sofia University and of seeds collected in the field in Bulgaria.
Following examination of recent fruit stones of three European species, C. tournefortii, C. caucasica and C.
australis, as well as of the North American C. occidentalis L., Matsutani (1987) proposed that Celtis fruit
stones could be identified as originating from one or other of two species groups within the genus.
C.
australis-type fruit stones have a clearly reticulate endocarp, whereas C. tournefortii-type fruit stones have
a relatively smooth endocarp with four prominent ridges.
Of the species examined by Matsutani, C.
australis-type included also C. caucasica, whereas C. occidentalis was placed in C. tournefortii-type. Our
examination of herbarium and field collected specimens included material of C. glabrata. The morphology
of the fruit stones of this material showed them also to be of C. tournefortii-type (Figure S1).
The Celtis fruit stones recovered from the Weichselian late-glacial sediments of the Ezero wetland were
about 4·0 – 4·2 mm in length and 3·5 – 4·0 mm in breadth, spherical and with four longitudinal ridges
meeting at right angles (Figure S1). They thus closely resemble modern material of C. tournefortii-type.
Given that both C. tournefortii and C. glabrata are today native in north-west Turkey, and the latter also in
southern Bulgaria (Browicz & Zieliński, 1977), the fossil fruit stones most likely represent one of these two
species.
Despite a thorough examination of large numbers of fruit stones of these two species, however,
we were unable to find any features that could be used to distinguish them. We therefore refer to the fruit
stones recovered from the sediments at Ezero as C. tournefortii-type.
In order to identify as precisely as possible the fossil Juniperus seeds recovered from the Weichselian lateglacial sediments at Ezero wetland, we carefully examined seeds of all those species of the genus native
today in Bulgaria, i.e. J. communis, J. deltoides R.P. Adams, J. excelsa and J. sabina (Tutin et al., 1993).
Comparison of the fossil seeds showed that they were very similar in morphology to those of the multiseeded junipers of Juniperus Sect. Sabina, represented in Bulgaria by J. excelsa and J. sabina (Farjon,
1992). Two additional species in this section occur in neighbouring regions, however:
J. foetidissima
extends from Albania, Macedonia and Greece east through southern Turkey, Cyprus and Lebanon to the
south-east Caucasus, and is found also in Crimea;
J. polycarpos K. Koch (Adams, 2001) extends from
north-east Turkey eastwards across central Asia to the Tien Shan and western Himalayas and south to Iran
and an outlier in Oman.
Of the two, only seeds of the first were available to us for examination.
All three
species of J. Sect. Sabina examined have ovoid/globose seeds with a pointed proximal tip and three
longitudinal ridges.
They are usually triangular in cross section, but occasionally nearly spherical.
bright or lighter-coloured area is often present on the wide curved end of the seed (Figure S1).
A
J. sabina
has the largest seeds, ca. 5 – 7 mm long, the other two species’ seeds being smaller (4·2 – 5·5 mm) with
concave walls.
Distinction between J. excelsa and J. foetidissima can be made using morphological
characteristics: the first species has distinctly ovoid seeds with a pointed proximal tip and 3 longitudinal
ridges, whereas the second has rather globose seeds with a less pronounced pointed proximal tip.
On the
basis of their size and morphology, we believe that the fossil seeds recovered most likely represent J.
excelsa.
However, given the limitations of the modern seed material available to us, we refer to them
cautiously as Juniperus cf. J. excelsa.
FIGURE CAPTION
Figure S1:
Celtis fruit stones and Juniperus seeds.
(a, b) Fossil fruit stones of Celtis tournefortii-type;
(c) Recent fruit stone of C. glabrata; (d, e) Fossil
seeds of Juniperus cf. J. excelsa; (f) Recent seed of J. excelsa. (a, b, d, e) recovered from the
Weichselian late-glacial sediments of Ezero wetland;
(c) collected by EM;
(f) herbarium material, Sofia
University, collected in the Struma river valley, Bulgaria.
REFERENCES
Adams, R. P. (2001) Geographic variation in leaf essential oils and RAPDs of Juniperus polycarpos
K. Koch in central Asia. Biochemical Systematics and Ecology, 29, 609-619.
Browicz, K. & Zieliński, J. (1977) Two new taxa within the Ulmaceae family for the flora of Bulgaria and their
geographical distribution. Fragmenta Flora Geobotanica, 23, 141-150.
Farjon, A. (1992) The taxonomy of multiseed junipers (Juniperus Sect. Sabina) in southwest Asia and east
Africa (Taxonomic notes on Cupressaceae I). Edinburgh Journal of Botany, 49, 251-283.
Matsutani, A. (1987) Plant remains from the 1984 excavations at Douara Cave. Paleolithic site of Douara
Cave and paleogeography of Palmyra basin in Syria. Part IV: 1984 Excavation. (ed. by T. Akazawa and
Y. Sakaguchi), Chapter 7, Bulletin No. 29, The University Museum, The University of Tokyo.
Tutin, T. G., Burges, N. A., Chater, A. O., Edmondson, J. R., Heywood, V. H., Moore, D. M., Valentine, D.
H., Walters, S. M. & Webb, D. A. (eds.) (1993) Flora Europaea, Vol. 1. Psilotaceae to Platanaceae.
Second Edition. Cambridge University Press, Cambridge.