NUCLEAR DNA CONTENT IN SOME GREEN TOADS ( Bufo viridis COMPLEX)
OF TURKEY AND IRAN
L. J. Borkin,
1
J. M. Rosanov,
2
and S. N. Litvinchuk
1,2
Submitted April 29, 2000.
15 specimens from western Turkey, northern and southern Iran were examined. According to external
characters and geographic position, the toads seem to belong to B. v. viridis , to the so-called Transcaspian
population group, and to B. v. kermanensis, respectively. The diploid level of toads was evidenced from
DNA flow cytometry. The distribution of diploid and polyploid toads in Western Asia is discussed.
Key words: Bufo viridis complex, Turkey, Iran, Genome size, DNA flow cytometry.
Green toads ( Bufo viridis complex) of Western
and Central Asia provide an exciting example of un-
usual speciation among animals. These common
toads are well known since the 18th century, although
twenty five years ago only were found (Mazik et al.,
1976), that some Asian members of the complex are
polyploid. The taxonomy of the B. viridis complex is
still quite confused. Despite a long list of synonyms,
last decades, some new species and subspecies have
been described by various authors (Eiselt and
Schmidtler, 1971, 1973; Mertens, 1971; Hemmer et
al., 1978; Pisanets, 1978a; Andrén and Nilson, 1979;
Pisanets and Szczerbak, 1979; Pisanets et al., 1996;
Khan, 1997; Fei et al., 1999; Stöck et al., 1999).
However, as yet taxonomic position and ploidy
level of many populations are unclear, and relation-
ships between members of the B. viridis complex
need further examination. Also the origin of poly-
ploidy in these toads is in dispute (Pisanets, 1978b,
1991; Borkin et al., 1986a, 1986b, 1986c; Roth,
1986; Roth and Ráb, 1986; Borkin and Kuzmin,
1988; Kudryavtsev et al., 1988; Borkin and Sokolo-
va, 1989; Mezhzherin and Pisanets, 1995a, 1995b;
Stöck and Große, 1997; Stöck, 1998; Stöck et al.,
1999). It is clear that a thorough revision of the B.
viridis complex is greatly needed, and most advances
in the study were and will be associated with an ap-
plication of cytogenetic and molecular techniques.
Unfortunately, some important localities are situated
in the areas of political instability and local conflicts,
sometimes, dangerous for foreign visitors.
Cytogenetic and biochemical studies revealed
three ploidy levels in green toads of Western and
Central Asia.
1. Diploid populations are distributed in the
Caucasus and, probably, Western Asia as well as in
the northern plains of the former Soviet Middle Asia
(e.g., Kryukov et al., 1985; Borkin et al., 1986a,
2001; Roth and Ráb, 1986; Stöck and Große, 1997).
They are treated as a number of subspecies of B. viri-
dis Laurenti, 1768. Another specific name, B. shaar-
tusiensis Pisanets, Mezhzherin et Szczerbak, 1996,
has been applied to green toads of southern
Tadjikistan.
2. Tetraploid populations occur in the areas of
the mountain ranges and, sometimes, adjacent plains,
situated in the south of the former Soviet Middle Asia
between the Caspian Sea and north-western China,
eastwards to south-western Mongolia (e.g., Kryukov
et al., 1985; Borkin et al., 1986a, 1986b, 1986c, 1995,
2001; Wu and Zhao, 1987; Dujsebayeva et al., 1997;
Stöck, 1998). Currently, tetraploid populations from
the former Soviet territory and Mongolia are united
under the arbitrary name B. danatensis Pisanets,
1978, whereas the toads of Kashgar, Xinjiang, China
were preliminary proposed to name B. nouettei
Mocquard, 1910 (Stöck, 1998). Moreover, in Xin-
jiang, three subspecies of B. danatensis are recog-
nized by Fei et al. (1999). However, some older
names are available and should be re-examined.
3. Triploid toads seem to be represented by two
different kinds.
1026-2296/2000 /0703-0 171 © 2000 Folium Publishing Company
Russian Journal of Herpetology Vol. 7, No. 3, 2000, pp. 171 – 180
1
Zoological Institute, Russian Academy of Sciences, Universitet-
skaya nab. 1, St. Petersburg 199034, Russia.
E-mail: borkin@spas.spb.su
2
Institute of Cytology, Russian Academy of Sciences, Tikhorets-
ky pr. 4, St. Petersburg 194064, Russia.