Lakušić, M. & Roumelioti, M. & Licata, F. & Bilancioni, M. & Ferreira, D.F. & Khalatbari, L. & Lakušić, V. & Vicente Liz, A. & Oliveira, R.N. de & Santos, B. & Simone, Y. & Patkó, L. & Abdulkarem, A. & Lee, B.P.Y-H. & El-Bana, M. & Al-Ansari, A. & Al-Attas, O. & Brito, J.C. (2026) -
Melanism in scorpions, reptiles and rodents inhabiting the volcanic fields of north-western Saudi Arabia. - Journal of Arid Environments,233: 105548, ISSN 0140-1963.

×Body colouration is involved in multiple aspects of species ecology and behaviour. Melanism, a common colour
polymorphism, has been associated with camouflage and thermoregulation, particularly in diverse, high-altitude
habitats of arid regions. This study reports the first case of melanism in the lacertid Acanthodactylus boskianus,
two scorpions, Leiurus haenggii and Compsobuthus manzonii, and the first records of brown-black melanistic
colouration in three rodent species, Acomys dimidiatus, Meriones crassus, and Sekeetamys calurus, in the dark lava
fields (harrat) of north-western Saudi Arabia. Additionally, it expands observations of melanism in the endemic
colubrid Rhynchocalamus hejazicus and provides the first documented records of brown-black melanistic Acomys
russatus for the region, consistent with earlier predictions. These observations suggest that colour polymorphism
may serve a cryptic function through background matching in both diurnal and nocturnal species, but other roles
of melanism should be further investigated. Despite their extent, lava fields in arid regions remain poorly studied
due to their remoteness and limited accessibility, yet they offer unique opportunities to investigate phenotypic
evolution in arid ecosystems.
Uller, T. & Feiner, N. & Sacchi, R. & Juffie, M. & Scali, S. & Pafilis, P. & Plavos, K. & Abalos, J. & Andrade, P. & Aguilar, P. & Salvi, D. & While, G.M. (2026) -
Adaptive spread of a sexually selected syndrome eliminates an ancient color polymorphism in wall lizards. - Science, 391 (6780): 64-68. 
×Genetically determined color morphs are found in many animals. Polymorphism can be maintained by social selection if competitive interactions allow each morph to increase in frequency when rare. This reliance on negative frequency–dependent selection should make color polymorphism vulnerable to the appearance of novel phenotypes that disrupt competitive interactions among morphs. We show that the origin and adaptive spread of a sexually selected syndrome in common wall lizards (Podarcis muralis) selectively eliminates alleles coding for alternative color morphs that have been maintained for millions of years. The results demonstrate how the arrival of a novel phenotype can disrupt balancing selection, providing a link between rapid phenotypic evolution and the loss of color polymorphisms.
1 new picture of Pedioplanis mayeri CHILDERS et al., 2021 from Namibia. (wild)