BIHAREAN BIOLOGIST 14 (2): 122-124 ©Biharean Biologist, Oradea, Romania, 2020

Article No.: e202302 http://biozoojournals.ro/bihbiol/index.html

New data on the distribution of the Bulgarian Bent-toed Gecko

(Mediodactylus danilewskii Strauch, 1887)

in Shumen town (NE Bulgaria)

Teodora KOYNOVA1,*, Dimitar DOICHEV1 and Nikolay NATCHEV1,2

1. Faculty of Natural Science, Shumen University, Universitetska 115, 9700 Shumen, Bulgaria

2. DIZ, Vienna University, Althanstrasse 14, 1090 Vienna, Austria

* Corresponding author, T. Koynova, E-mail: t.koynova@shu.bg

Received: 29. March 2020 / Accepted: 03. July 2020 / Available online: 10. July 2020 / Printed: December 2020

Abstract. Recently, the phylogeny of the “Kotschy’s gecko” (Mediodactylus kotschyi Steindachner,1870) was revised, and the Black sea

populations were distinguished as a new species – the Bulgarian Bent-toed Gecko (Mediodactylus danilewskii Strauch, 1887). This

species was never reported for the inland of north Bulgaria (except for one already extinguished population near the Danube river)

until 2015. New information on the distribution of the geckos on the territory of Shumen is presented and notes on the sustainability

of the population in the region in the last five years are provided.

Key words: distribution, new locality, population, gecko, monitoring, ecology.

For Bulgaria the “Kotschy’s gecko”, (Mediodactylus kotschyi

Steindachner,1870) is considered as a species complex (see

Popgeorgiev et al. 2019). Kotsakiozi et al. (2018) have made a

multilocus phylogenetic analysis and divided the genus

Mediodactylus into five clades/species: M. kotschyi; M.

orientalis; M. danilewskii; M. bartoni and M. oertzeni. The

Mediodactylus populations along the Black Sea coast (Black

Sea region and south-western Anatolia) were classified as M.

danilewskii. To date on the territory of Bulgaria were detected

two species – M. kotschyi (with two subclades M. k. rumelicus

and M. k. bibroni) and M. danilewskii (the former M. kotschyi

danilewskii obtained a status of a species).

In Bulgaria, the geckos predominantly inhabit human

settlements (Petkov, 2002, Mollov, 2005, Pulev et al. 2014,

Mollov et al. 2015, Popgeorgiev et al. 2019)) - there are only

few known populations from natural habitats (see Beshkov

& Nanev, 2002). In the northern part of the country, the

species was found along the Black sea coast (see Stoyanov et

al. 2011) and a single population was detected at “Orlova

chukka” cave in the region of Ruse (the last report for this

population was provided by Tzankov et al. 2009). As stated

by Boyan Petrov (see Koynova et al. 2017), the population of

M. danilewskii in the region of the cave had disappeared

before 2017.

The first record of M. danilewskii from Shumen town

(inland NE Bulgaria), was provided by a local hobby

naturalist (Radoslav Tzvetkov) in the summer of 2015.

Thanks to the efforts of local volunteers, we were able to

confirm the presence of M. danilewskii in Shumen trough the

last five years (except 2017) and gained new data on the diet

of the species which will be subject of a future publication.

The species was detected several times in 2016 (see Koynova

et al. 2017). In 2017 there were no recorded observations. The

lack of observations may be explained by the exceptionally

cold and long winter and the low summer temperatures,

which may had impacted the activity patterns of the species

and this way had limited its detectability. Another possible

reason is that the only two old low-profile buildings in the

region of detection were destroyed in the spring of 2017 and

new construction works had started. Apparently, the older

buildings (43.274352°N, 26.926885°E; 231 m a.s.l.; Datum:

Figure 1. A subadult specimen of M. danilewskii observed on a facade

of a newly constructed building in Shumen town (NE Bulgaria).

WGS 84) were the overwintering places for that local

population of the gecko.

In 2018 M. danilewskii was not detected on the location

known to that date, however in two new sites we recorded

geckos (Figure 1). The exact coordinates of these localities

are 43.278428°N, 26.920267°E; 237 m a.s.l and 43.271875°N,

26.932058°E; 213 m a.s.l. (both Datum: WGS 84)

In 2019 the species was observed on all of the three sites

(see Figure 2). The latest registered animals were two

juvenile geckos with estimated body length (SVL) of 15 mm

Data on M. danilewskii in Bulgaria

123

Figure 2. Map of detected separate localities numbered 1, 2 and 3 of M. danilewskii in the central part of

Shumen (NE Bulgaria).

Figure 3. Маp of settlements in NE Bulgaria, where geckos were detected - the represented subadult gecko specimen from Novi Pazar was

photographed on 07.08.2016 by Sevinch Faik Basri. The smaller map (modified from Stojanov et al. 2011) represents the distribution of the

Mediodactylus kotschyi complex on the territory of Bulgaria (the dots represent the locations of the gecko habitats and the square indicates

the geographic position of Shumen town).

(detected on 09.09.2019) and a subadult with SVL of 35 mm

(detected on 16.09.2019), which may be a proof that the

geckos are breeding.

During the five-year monitoring, the most of the

observations were made at night, however several

individuals were spotted during the day. The lizards were

observed not only on the facades of the buildings, but also

indoors. Similar behavior was also described for the gecko

populations in Plovdiv city (South Bulgaria) by Mollov

(2019). In contrast to the first observations in 2015 and 2016,

which were in regions with houses of low profile, the later

were made in neighborhoods with multiple-staged high

buildings. Such habitats were recently reported for M.

danilewskii from Bucharest, Romania where it was observed

T. Koynova et al.

124

even in business and economic centers. To date there are no

firm evidences whether this particular Romanian population

is resident or these are accidentally transferred animals (see

Gherghel & Tedrow, 2019).

Based on our monitoring and observations over the last 5

years, we can determine that M. danilewskii is resident in

Shumen. Presumably the animals were initially brought to

the town by a human-mediated transportation and the

species has successfully adapted to the local habitats and has

established a reproducing population. Another possible

hypothesis could be based on the expansion of the range of

the species related to the current climatic conditions. A

support for such “natural” appearance of the lizards in

Shumen could be the finding of a subadult gecko in the town

of Novi Pazar made by Sevinch Faik Basri (43.351387°N,

27.190063°E; 108 m a.s.l. Datum: WGS 84). This town is

positioned between the populations along the Black sea and

the town of Shumen (see Figure 3).

Acknowledgement. This work was partly supported by the

Research Fund of the Konstantin Preslavsky University of Shumen

(Grant No. RD-08-104/30.01.2020). We are thankful to Daniel

Jablonski (Comenius University, Bratislava, Slovakia) for comments

on the phylogenetics. Two anonymous reviewers are acknowledged

for their helpful comment, which contributed to the improvement of

the manuscript.

References

Beshkov, V., Nanev, K. (2002): The amphibians and reptiles in Bulgaria. 1st

Edition, Pensoft, Sofia-Moscow. [in Bulgarian]

Gherghel, I., Tedrow, R. (2019): Manmade structures are used by an invasive

species to colonize new territory across a fragmented landscape, Acta

Oecologica 101: 103479.

Kotsakiozi, P., Jablonski, D., Ilgaz, C., Kumlutaş, Y., Avcı, A., Meiri, S., Itescu,

Y., Kukushkin, O., Gvoždík, V., Scillitani, G., Roussos, S.A., Jandzik, D.,

Kasapidis, P., Lymberakis, P., Poulakakis, N. (2018): Multilocus phylogeny

and coalescent species delimitation in Kotschy’s gecko, Mediodactylus

kotschyi: hidden diversity and cryptic species. Molecular Phylogenetics and

Evolution 125: 177-187.

Koynova, T., Tzankov, N., Popgeorgiev, G., Naumov, B., Natchev, N. (2017): A

new distribution record of the Kotschy’s Gecko (Mediodactylus kotschyi) from

inland north-eastern Bulgaria. Herpetology Notes 10: 1-2.

Mollov, I. (2005): A study on the amphibians (Amphibia) and reptiles (Reptilia)

in three urban protected areas in the town of Plovdiv (South Bulgaria).

Scientific Studies of the University of Plovdiv - Biology, Animalia 41: 79-94.

Mollov, I., Georgiev, D., Basheva, S. (2015): Is the Kotschy’s Gecko

Mediodactylus kotschyi (Steindachner, 1870) (Reptilia: Gekkonidae) active

during the winter? ZooNotes 84: 1-3.

Mollov, I. (2019): Urban Ecology Studies of the Amphibians and Reptiles in the

City of Plovdiv, Bulgaria, Cambridge Scholars Publishing, Newcastle upon

Tyne, UK.

Petkov, V. (2002): Second record of the Balkan gecko (Cyrtodactylus kotschyi

danilewskii Strauch 1887) in the region of Russe. Historia Naturalis Bulgarica

15: 156-157.

Pulev, A., Domozetski, L., Sakelarieva, L. (2014): Distribution of Kotschy`s

Gecko Mediodactylus kotschyi (Steindachner, 1870) (Reptilia: Gekkonidae) in

South-West Bulgaria. Ecologica Balkanica 6: 75-81.

Popgeorgiev, G., Naumov, B., Kornilev, Y., Vergilov, V., Slavchev, M.,

Lukanov, S., Dyugmegdzhiev, A., Stoyanov, A., Dobrev, D., Tzankov, N.

(2019): Diversity and distribution of Amphibians and Reptiles in the

Bulgarian Part of the Lower Danube. pp. 284-314. In: Shurulinkov, P.,

Hubenov, Z., Beshkov, S., Popgeorgiev, G. (eds.), Biodiversity of the

Bulgarian-Romanian Section of the Lower Danube.

Stojanov, A., Tzankov, N., Naumov, B. (2011): Die Amphibien und Reptilien

Bulgariens. 1st Edition, Frankfurt am Main, Germany: Edition Chimaira.

Tzankov, N., Naumov, B., Grozdanov, A., Peshev, D., Vasilev, A. (2009): The

herpetofauna of northern Black sea coast. Biotechnology & Biotechnological

Equipment 23(1): 123-126.