During this spring trip to eastern Peloponnese we had rather wet weather conditions which thwarted our initial plans to explore the higher altitudes of the Parnon mountains. But luckily, the area also has some beautiful lowland habitats. During this trip, we focused on a very common species: Podarcis peloponnesiacus (Peloponnese Wall Lizard), which inhabits the complete Peloponnese except of some parts in the north-west. Although this colorful Wall Lizard species may be supposed to be sufficiently known, exploring these lizards turned out quite exciting.

For eastern Peloponnese, the subspecies Podarcis peloponnesiacus thais has been described in 1960 by BUCHHOLZ and recent genetic analysis revealed that it even could be regarded as a separate species (SPILANI et al., 2019). According to this, the distribution range of this lizard covers the Peloponnese east coast (Korinthia, Argolis, Arcadia and Lakonia prefectures). For the putative distribution area see map below. As the SPILANI et al. paper doesn’t provide a formal species description, we keep referring to these lizards as subsp. thais, at the moment.

During this trip, we were keen on understanding the differences between subsp. thais and the nominate subspecies with regard to field characters. Unfortunately, BUCHHOLZ’ original description was based on very few specimens from Argolis and turned out to be not very reliable. Regarding the coloration of subsp. thais, BUCHHOLZ mentions the following characters:

- Males have white throats

- Both sexes show a short vertebral line which ends behind the shoulders

- Males with dark supra-dorsolateral bands (similar to females)

- Males without green on back

Visiting several stations, we found a wide variability in color, even within the same population. About half of the males we saw showed whitish throats, but orange throats (like in the nominate subspecies) frequently occurred. The vertebral line is short in many cases – but not always. Males often show dark bands on back but may also have very reduced dark pattern. At least, we can confirm that males of the eastern form seem to show no green colors on their back (whereas males of the nominate subspecies frequently have greenish dorsolateral lines).

From our point of view, a good field character for subsp. thais seems to be the extensive blue coloration on the flanks of males. In contrast to this, males of the nominate subspecies only show some well-defined blue shoulder spots, in general. Furthermore, males of subsp. thais sometimes have bluish tails, which we never saw in the nominate subspecies.

According to SPILANI et al., subsp. thais was separated from the nominate subspecies in early Pleistocene. In this case, cooler climate could have separated the populations with the mountain ranges of Parnon, Mainalo, Olygirtos and Killini as natural barriers.

Note that this report represents our preliminary point of view – future research possibly will provide a deeper understanding.

Our first station, Tolo, gave us a wet welcome with heavy thunderstorms. Anyhow, we were able to do some visits in the Argolis hillsides and at the coast near Argos. There we got first insights about the huge variability of the Peloponnese Wall Lizards, as the following pictures demonstrate.

The mountains of Leonidi are a popular destination for climbing sports. Unfortunately, unstable weather conditions prevented us from in-depth exploring these scenic area. But during our stay, we came across several color morphs of Podarcis peloponnesiacus thais, again. Further south, at the southern slopes of Parnon, uniform specimen without dark pattern seem to frequently occur.

This village on an iconic rock off the south-eastern Peloponnese coast is a busy tourist place. However, we heard that this area is inhabited by a strange morph of Podarcis peloponnesiacus: These lizards even have erroneously been identified as Podarcis erhardii (Erhard’s Wall Lizard) until genetic analysis revealed they were Podarcis peloponnesiacus. And indeed, the lizards from Monemvasia island looked odd, which may be caused by genetic isolation.

During our stay at Monemvasia, the weather finally collapsed on eastern Peloponnese and so we decided to visit our friend Philippos Katsiyiannis in the Patras area, who gave us a warm welcome.

After a long ride we reached the north-west at last and fortunately it stopped raining. We headed to Erymanthos, a wild and poorly known mountain range with beautiful nature, where we explored a nice and remote valley. But strangely, despite of perfect conditions, Algyroides moreoticus (Greek Algyroides) was we only lacertid we saw. In particular, Podarcis peloponnesiacus seems to be rather rare with patchy distribution in that part of Peloponnese. Afterwards we headed west to the Santomeri mountain, an isolated limestone rock which is inhabited by Podarcis peloponnesiacus (nominate subspecies), Greek Algyroides and Lacerta trilineata (Balkan Green Lizard).

We spent our last day at the beautiful coast of Kalogria with its amazing pine forest which is populated by Podarcis ionicus (Ionian Wall Lizard) and Lacerta trilineata. Afterwards, a short stop-over near Patras was rewarded with some nice Lacerta trilineata shots and then we headed back to Athens for our return flight.

BUCHHOLZ, K.F. (1960) - Zur Kenntnis von Lacerta peloponnesiaca (Reptilia: Lacertidae). - Bonner zoologische Beiträge, Bonn, 11 (1): 87-107.

SPILANI, L. & BOUGIOURI, K. & ANTONIOU, A. PSONIS, N. & POURSANIDIS, D. & LYMBERAKIS, P. & POULAKAKIS, N. (2019) - Multigene phylogeny, phylogeography and population structure of Podarcis cretensis species group in south Balkans.- Molecular Phylogenetics and Evolution, 138: 193-204.