| Eremias brevirostris BOULENGER, 1887 Eremias bernoullii SCHENKEL, 1901 Mesalina brevirostris fieldi HAAS & WERNER, 1969 Mesalina bernoullii ŠMÍD et al., 2017 |
| Mesalina microlepis is morphologically very similar to M. bernoullii and, contrary to what ANGEL (1936) suggested it cannot be distinguished from it by the numbers of dorsal and gular scales, and subdigital lamellae. The only morphological character that discriminates the species is the structure of the lower eyelid window. All specimens of M. microlepis (including the holotype) possess a window consisting of more than three roughly equal semitransparent scales whereas the window of M. bernoullii, M. brevirostris s. s. and M. saudiarabica consists of 1–3 larger semitransparent scales (see Fig. 3 in MAYER et al. 2006). Mesalina microlepis and M. bernoullii have been confirmed to occur syntopically in western Syria (MAYER et al. 2006). The presence of M. microlepis in Jordan and Turkey is confirmed based on specimens with similar eyelid window structure (HAAS & WERNER 1969; KUMLUTAŞ et al. 2002).
Source: ŠMÍD et al. 2017. |
Schenkel, E. (1901) - Achter Nachtrag zum Katalog der herpetologischen Sammlung des Basler Museums. - Verhandlungen der Naturforschenden Gesellschaft in Basel, 13, 142-199.  Haas, G. & Werner, Y.L. (1969) - Description of Mesalina brevirostris fieldi. – In: “ Lizards and snakes from Southwestern Asia, collected by Henry Field”. - Bulletin of the Museum of Comparative Zoology at Harvard College, 138: 327-406. Pl. 1-21.  Mayer, W. & Moravec, J. & Pavlicev, M. (2006) - Differentiation within Syrian populatrions of the lizard Mesalina brevirostris. - In: Corti, C., Lo Cascio, P. & M. Biaggini (eds.): Mainland and insular lacertid lizards: a mediterranean perspective. 125-131.  × ree more or less different morphotypes of Mesalina brevirostris Blanford 1874 have
been distinguished within the territory of Syria: (1) Lowland form, (2) Western (interme-
diate) form and (3) Jabal al Arab form. We sequenced parts of the mitochondrial gene for
cytochrome b (836 bp) of M. brevirostris samples from four Syrian and two Jordan localities
and parts of the 12S rRNA and 16S rRNA genes of two selected Syrian samples to estimate
the phylogenetic relationships among the given morphotypes.
Two main clades with a divergence of about 10% in cyt-b were obtained. e first
one involves the representatives of all three morphotypes and is divided further into three
weakly divergent subclades: (i) Lowland form and partly also the Western form, (ii) J. al
Arab form and population from northern Jordan, (iii) population from the eastern Jordan
(area of Azraq). is situation indicates a high variability of haplotypes in a relatively small
area. e second main clade consists of the remaining representatives of the Western form
and reveals a cryptic undescribed taxon being hidden (syntopic occurrence) within the
Western form (s.l.).
e results suggest that the Syrian Lowland and J. al Arab forms might represent two
different subspecies of M. brevirostris which evolved in a comparatively short time. e
former form has been traditionally associated with the name M. b. brevirostris. e latter
can be assigned to the name M. b. microlepis Angel 1936. A problem rises from the position
of the holotype of microlepis, which morphologically fits rather the J. al Arab form than the
other morphotypes, although according to the molecular data the today’s topotypes belong
to the Lowland form. is can be explained by the changes in the distribution of the respec-
tive form due to current aridisation process. A particular question concerns the taxonomic
position of the Azraq population.
Finally, only the cryptic undescribed taxon in western Syria may be assigned to the in-
termediate western morphotype. e degree of morphological differentiation of this form
is discussed. Šmíd, J. & Moravec, J. & Gvoždík, V. & Štundl, J. & Frynta, D. & Lymberakis, P. & Kapli, P. & Wilms, T. & Schmitz, A. & Shobrak, M. & Hosseinian Yousefkhani, S. & Rastegar-Pouyani, E. & Castilla, A.M. & Els, J. & Mayer, W. (2017) - Cutting the Gordian Knot: Phylogenetic and ecological diversification of the Mesalina brevirostris species complex (Squamata, Lacertidae). - Zoologica Scripta, 46 (6): 649-664. × Mesalina are small lacertid lizards occurring in the Saharo-Sindian
deserts from North Africa to the east of the Iranian plateau. Earlier phylogenetic studies indicated that there are several species complexes within the genus and that thorough taxonomic revisions are needed. In this study, we aim at resolving the phylogeny and taxonomy of the M. brevirostris species complex distributed from the Middle East to the Arabian/Persian Gulf region and Pakistan. We sequenced three mitochondrial and three nuclear gene fragments, and in combination with species delimitation and species-tree
estimation, we infer a time-calibrated phylogeny of the complex. The
results of the genetic analyses support the presence of four clearly delimited species in the complex that diverged approximately between the middle Pliocene and the Pliocene/Pleistocene boundary. Species distribution models of the four species show that the areas of suitable habitat are geographically well delineated and nearly allopatric, and that most of the species have rather divergent environmental niches.
Morphological characters also confirm the differences between the species, although sometimes minute. As a result of all these lines of evidence, we revise the taxonomy of the Mesalina brevirostris species complex. We designate a lectotype for Mesalina brevirostris Blanford, 1874; resurrect the available name Eremias bernoullii Schenkel, 1901 from the synonymy of M. brevirostris; elevate M. brevirostris microlepis (Angel, 1936) to species status; and describe Mesalina saudiarabica, a new species from Saudi Arabia.
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