Underground cryptic speciation within the Maghreb: Multilocus phylogeography sheds light on the diversification of the checkerboard worm lizard Trogonophis wiegmanni

A Phylogenetic Assessment of Nematodes (Oxyuroidea: Pharyngodonidae) Infecting Moroccan Lizards

Molecular tools can be used to estimate the phylogeny of species and to identify cryptic diversity, but their use for parasites has lagged behind that of free-ranging organisms. As an example, in North Africa there is minimal molecular data available for helminth parasites of lizards. In this work we used two molecular markers (the nuclear 18S rRNA and the mitochondrial Cytochrome c Oxidase subunit 1) to investigate the diversity of nematodes of the family Pharyngodonidae parasitizing three genera of lizards from Morocco (Chalcides, Quedenfeldtia and Tarentola) and to explore their co-evolutionary history. Morphological assessments indicated that members of three genera were present: Spauligodon, Thelandros, and Parapharyngodon. Phylogenetic analysis of 18S rRNA sequences indicated the monophyly of the genus Spauligodon, and that some lineages could be distinguished, including Spauligodon auziensis from the host species Tarentola mauritanica, and another unnamed lineage from hosts of the genus Chalcides. However, with this slow-evolving marker some species could not be distinguished. The genus Thelandros was not monophyletic, although relationships were not strongly supported. Analysis of the faster evolving mitochondrial marker clearly separated various species of Spauligodon, as well as distinct unnamed lineages identified in the host genus Chalcides and the host Quedenfeldtia moerens.

New host and locality records of helminths' infection of seven lizards from Morocco

Morocco has a great diversity of reptiles; more than 26% of the herpetofauna species are considered to be endemic. Nevertheless, there is little information available on helminth parasites of Moroccan lizards. The purpose of this article is to establish a helminth list using non-invasive methods for natural populations of seven lizard species: Acanthodactylus maculatus, Chalcides mionecton, Chalcides montanus, Chalcides polylepis, Quedenfeldtia moerens, Quedenfeldtia trachyblepharus, and Tarentola mauritanica. For each species, prevalence and intensity of infection were given as well as their relationship to some determinant parameters (sex, age class, size, altitude, and seasons). Four species of nematodes, Parapharyngodon micipsae, Pharyngodon mamillatus, Spauligodon auziensis, Thelandros alatus, and unassigned Spauligodon were found. Mean helminth intensity for the seven lizard species was 7.3 ± 16.2 SD (range = 1-92 in infected lizards), with total infection prevalence of 5.6%. Mixed infections were observed in Chalcides montanus and Chalcides polylepis co-infected by Pharyngodon mamillatus and Spauligodon sp. Furthermore, the intensity of infection by nematodes were significantly different among the seven studied species. The nematode infection in Chalcides mionecton were related to sex, host size, and altitude; in Chalcides polylepis to the host age; in Quedenfeldtia trachyblepharus to elevation, age, and host size; and in Tarentola Mauritanica to age, body size, seasons, and altitude. In conclusion, our study provides data about nine new host and locality records and the effect of some determinant factors on host parasitism.

Reptile biodiversity in Souss-Massa National Park: an internationally important hotspot in the Mediterranean region

Souss-Massa National Park (SMNP) is Morocco’s first coastal national park, created to preserve the high diversity of its continental and marine environments. Reptiles play an essential role in balancing SMNP ecosystems, yet little work has been done to study this fauna. The present work aims at providing the first reptile inventory of SMNP since its establishment in 1991. During the period 2019 to 2020, several field surveys were carried out at 30 sites using time-constrained visual encounter surveys (TCVES), with a total sampling effort of 300 person-hours. An inventory of 23 reptile species (including four endemic species) was obtained by combining TCVES results with additional data recorded during random encounters or provided by SMNP researchers. Based on TCVES data, both sampling effort and inventory completeness were evaluated by constructing sample-based accumulation curves and calculating non-parametric estimators (Chao 1, Chao 2, Jackknife 1 and Jackknife 2). These species richness estimators suggest that the current inventory is likely to be complete. Despite its small surface area, SMNP contains nearly 20% of all known Moroccan reptile species and constitutes an important biodiversity hotspot for reptiles in the Mediterranean Region. In terms of reptile conservation concern, five species in SMNP are classified as “vulnerable”, while two species are classified as “near threatened” on the IUCN Red List, underscoring the importance of protected areas for those species.

Biogeographic and demographic history of the Mediterranean snakes Malpolon monspessulanus and Hemorrhois hippocrepis across the Strait of Gibraltar

BACKGROUND

The contribution of North Africa to the assembly of biodiversity within the Western Palaearctic is still poorly documented. Since the Miocene, multiple biotic exchanges occurred across the Strait of Gibraltar, underlying the high biogeographic affinity between the western European and African sides of the Mediterranean basin. We investigated the biogeographic and demographic dynamics of two large Mediterranean-adapted snakes across the Strait and assess their relevance to the origin and diversity patterns of current European and North African populations.

RESULTS

We inferred phylogeographic patterns and demographic history of M. monspessulanus and H. hippocrepis, based on range-wide multilocus data, combined with fossil data and species distribution modelling, under present and past bioclimatic envelopes. For both species we identified endemic lineages in the High Atlas Mountains (Morocco) and in eastern Iberia, suggesting their persistence in Europe during the Pleistocene. One lineage is shared between North Africa and southern Iberia and likely spread from the former to the latter during the sea-level low stand of the last glacial stage. During this period M. monspessulanus shows a sudden demographic expansion, associated with increased habitat suitability in North Africa. Lower habitat suitability is predicted for both species during interglacial stages, with suitable areas restricted to coastal and mountain ranges of Iberia and Morocco. Compiled fossil data for M. monspessulanus show a continuous fossil record in Iberia at least since the Pliocene and throughout the Pleistocene.

CONCLUSIONS

The previously proposed hypothesis of Pleistocene glacial extinction of both species in Europe is not supported based on genetic data, bioclimatic envelopes models, and the available fossil record. A model of range retraction to mountain refugia during arid periods and of glacial expansion (demographic and spatial) associated to an increase of Mediterranean habitats during glacial epochs emerges as a general pattern for mesic vertebrates in North Africa. Moreover, the phylogeographic pattern of H. hippocrepis conforms to a well-established biogeographic partition between western and eastern Maghreb.

Revision shock in Pacific oysters taxonomy: the genus Magallana (formerly Crassostrea in part) is well-founded and necessary

The description of the genus Magallana provoked taxonomic ‘revision shock’ among Bayne and colleagues, who criticised: (1) the supporting evidence for this taxonomic change, (2) the procedure used and (3) its impact on the nomenclatural stability of oysters. Here, we demonstrate that the description of the genus Magallana fulfils the norms of taxonomic and indexing revisions, and is well-founded on a scientific basis. The clade named Magallana is supported by a robust phylogeny based on comprehensive taxon sampling, independent datasets and varied analytical methods. A new maximum likelihood phylogenetic analysis of oysters, based on mitochondrial gene order data (representing molecular phenotypes above the sequence level), has provided additional support for this classification. These results are fully consistent with all previously published phylogenetic studies, thus providing an unambiguous indication of the stability of the clade that meets all the currently accepted criteria for naming clades as taxa. We show that, while the criterion of ‘morphological diagnosability’ is not applicable at any level of oyster classification, several striking molecular phenotypes are diagnostic of Magallana, both at the nuclear and the mitochondrial genome level. The classification with three genera Magallana, Crassostrea and Talonostrea reflects the evolutionary diversity of Crassostreinae and is consistent with taxonomic ranking criteria adopted for other oyster subfamilies.

Systematics, biogeography and evolution of the Saharo-Arabian naked-toed geckos genus Tropiocolotes

Plate tectonics constitute one of the main mechanisms of biological diversification on Earth, often being associated with cladogenetic events at different phylogenetic levels, as well as with exchange of faunas and floras across previously isolated biogeographic regions. North Africa and Arabia share a complex geological history that dates back to the break-up of the Arabian plate from the African plate ~30-25 Mya, followed by various geological events, such as the formation of the Red Sea or the connection between the African, Arabian and Eurasian plates. Species with Saharo-Arabian distributions have shown a close association between their evolutionary history and these geological events. In this study, we investigate the systematics, biogeography and evolution of the genus Tropiocolotes, a group of small ground-dwelling geckos, comprised by 12 species distributed from the Atlantic coast of North Africa to southwestern Iran. Species delimitation analyses uncovered the existence of high levels of undescribed diversity, with forms here considered at the species level including Tropiocolotes tripolitanus (Mauritania and southern Morocco), T. nattereri (southern Israel) and T. scorteccii (Yemen and Oman). Phylogenetic and biogeographic analyses recovered two main clades, an exclusively African clade and a Saharo-Arabian clade, that split ~25 Mya following the vicariant event mediated by the separation of the Arabian and African plates. The complex geological activity around the Red Sea is associated with the diversification within the Saharo-Arabian clade, including the colonization of North Africa from a second Tropiocolotes group. Results also provide new insights into the geographic distribution of Tropiocolotes nubicus, previously considered as exclusively associated to the Nile River valley, extending its known distribution further west, up to the Central Mountains of the Sahara. Accordingly, the Nile River seems to act as a major biogeographic barrier, separating Tropiocolotes nubicus and T. steudneri in their western and eastern margins, respectively.

Phylogeny and biogeography of the African Bathyergidae: a review of patterns and processes

Background

We review genealogical relationships, biogeographic patterns and broad historical drivers of speciation within the Bathyergidae, a group of endemic African rodents, as well as identify key taxa which need further research.

Methods

We sourced comparable cytochrome b sequence data (comparable data available for all members for the Family) and geographic information for all six genera of the African subterranean rodent. This information was combined into the most comprehensive and geographically representative evolutionary study for the Bathyergidae to date.

Results

Species richness within the Bathyergidae appears to be underestimated, with undescribed taxa in five of the six genera. Biogeographic patterns suggest large historical distributions, which were repeatedly fragmented by major landscape changes (especially rifting, uplift and drainage evolution) since the Miocene. Aside from vicariant events, other factors (ecological specialization, population-level responses and climatic change) may have been instrumental in driving divergences in the Bathyergidae. As such, adaptive differences may exist among both populations and species across their discrete ranges, driving independent evolutionary trajectories among taxa. In addition, highly fragmented distributions of divergent (and often relict) lineages indicates the possibility of narrow endemics restricted to diminishing suitable habitats. From this, it is clear that a systematic revision of the Bathyergidae is necessary; such a revision should include comprehensive sampling of all putative taxa, the addition of genomic information to assess adaptive differences, as well as ecological information.

Comparative phylogeography of amphibians and reptiles in Algeria suggests common causes for the east-west phylogeographic breaks in the Maghreb

A series of phylogeographic studies in the Maghreb identified a repeated pattern of deep genetic divergence between an eastern (Tunisia) and western (Morocco) lineage for several taxa but lack of sampling in Algeria made it difficult to know if the range limits between the eastern and western lineages were shared among taxa or not. To address this question, we designed a comparative phylogeographic study using 8 reptile and 3 amphibian species with wide distribution in the Maghreb as models. We selected species where previous studies had identified an East-West phylogeographic divide and collected sampled in Algeria to 1) examine whether the simple East-West divergence pattern still holds after filling the sampling gap in Algeria or if more complex diversity patterns emerge; 2) if the E-W pattern still holds, test whether the limits between the E and W clades are shared between species, suggesting that common historical process caused the E-W divergences; 3) if E-W limits are shared between species, use information on the age of the divergence to identify possible geological or climatic events that could have triggered these E-W differentiations. We found that the E-W pattern was generally maintained after additional sampling in Algeria and identified two common disjunction areas, one around the Algeria-Morocco border, the other one in Kabylia (central Algeria), suggesting that common historical mechanisms caused the E-W divergences in the Maghreb. Our estimates for the times to most common recent ancestors to the E and W clades span a wide range between the Messinian salinity crisis and the Plio-Pleistocene limit (except for one older split), suggesting different origins for the initial divergences and subsequent preservation of the E and W lineages in common climatic refugia in the west and the east of the Maghreb.