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[Oct 16, 2025] The Reinstated Genus Pitardia: Confirmation of Its Affiliation with the Subtribe Menthinae (Lamiaceae)

This study addresses the systematic position of Nepeta nepetoides within the family Lamiaceae. To clarify its phylogenetic placement, molecular analyses were performed using several markers representing different genomic compartments: four chloroplast DNA markers (ycf1, the spacers ycf1–rps15, trnL–trnF, and rpl32–trnL), two nuclear ribosomal DNA markers (ITS and ETS), and a low-copy nuclear gene (PPR-AT3G09060). These markers, commonly employed in phylogenetic investigations of vascular plants, are particularly informative for resolving relationships among closely related species and genera.

The results derived from the three datasets are fully congruent: the four analyzed populations of Nepeta nepetoides form a well-supported, distinct clade that is sister to other members of the subtribe Menthinae, rather than to those of the Nepetinae. Consequently, this species should no longer be retained within the genus Nepeta but must be transferred to the genus Pitardia.

Pitardia can be distinguished from Nepeta by several diagnostic morphological traits: the presence of two stamens and the absence of staminodes (four stamens in Nepeta), a calyx tube with 10 veins (typically 15 [13–17] in Nepeta), and a convex, entire median lobe of the lower corolla lip (usually crenate in Nepeta).

Pitardia nepetoides Batt. ex Pit. is hereby reinstated, its lectotype is designated, and Pitardia caerulescens Maire and Pitardia gracilis Andr. are treated as synonyms.

Ref. Homrani Bakali A., Dirmenci T., Celep F. & Drew B.T., 2025 - Pitardia resurrected: A new member of subtribe Menthinae (Lamiaceae). Taxon, https://doi.org/10.1002/tax.70053

Posted by Jean-Paul Peltier.

[Jul 8, 2025] Evolutionary History of Euphorbia balsamifera

From a phylogenetic perspective, Euphorbia balsamifera, found in the arid regions of northwestern Africa and the Canary Islands, is closely related to Euphorbia adenensis, which originates from the Eritrea-Arabia region. These two species share a common ancestor that likely emerged several million years ago.

Molecular data suggest that the divergence between E. balsamifera and E. adenensis occurred during the Pliocene, a period spanning approximately 5.3 to 2.6 million years ago. This era coincides with a major episode of climate aridification in the subtropical regions of the Old World, leading to the fragmentation of forest habitats in favor of more open and arid landscapes. These new environmental conditions likely facilitated a rapid adaptive radiation of the ancestral group, meaning the emergence of several lineages specialized for arid habitats.

In this context, E. balsamifera is thought to have colonized the Canary Islands from northwestern Africa. This colonization may be explained by the "surfing syngameon" mechanism—an evolutionary hypothesis in which a flexible gene pool (or syngameon) "surfs" waves of dispersal into new territories while maintaining sufficient genetic diversity to allow rapid adaptation to novel environments.

Computer models using convolutional neural networks (a form of artificial intelligence) suggest that E. balsamifera first settled on the eastern islands (Lanzarote, Fuerteventura), before migrating westward (Tenerife, Gran Canaria).

Contrary to what one might assume, the populations in North Africa are not remnants of an ancestral continental population. Instead, they result from migratory events originating from the islands of Lanzarote and Fuerteventura. These back-colonization events likely occurred during the Middle Pleistocene, although this still requires confirmation.

This finding challenges the notion that islands merely "receive" genetic diversity from the continent. In this case, the Canary Islands actually generated new genetic diversity that subsequently spread back to the African mainland.

Ref. : Rincón-Barrado M., Villaverde T., Perez M.F., Sanmartín I. & Riina R., 2024 - The sweet tabaiba or there and back again: phylogeographical history of the Macaronesian Euphorbia balsamifera. Annals of Botany 133 : 883–903. https://doi.org/10.1093/aob/mcae001, available online at www.academic.oup.com/aob

Posted by Jean-Paul Peltier.

[Jun 28, 2025] Multiplication of the Argan Tree: Systematic Review and Meta-Analysis Using the PRISMA Method

This publication presents a synthesis of research studies focusing on the various methods of argan tree (Sideroxylon spinosum L.) propagation. It is based on the PRISMA method (Preferred Reporting Items for Systematic Reviews and Meta-Analyses), which is recognized for structuring and enhancing the transparency of systematic reviews and meta-analyses.

The literature search was conducted using the same keywords in the Scopus and Web of Science databases, selecting publications in English and French published between 2000 and 2024. Using the PRISMA method, 55 articles were selected, the majority of which (36) originate from Morocco, the native country of the argan tree.

The bibliometric analysis, performed using the VOSviewer software, enabled the visualization of links between the main keywords related to argan tree research. This map highlights the central position of germination, around which micropropagation, seed sowing, in vitro culture, and vegetative propagation are organized.

The discussion compares the different techniques: seed germination, which has a low success rate, is contrasted with the advantages of cutting and grafting, which allow for rapid rooting and greater genetic stability. In vitro micropropagation also appears to be a promising method, although it requires strict acclimatization conditions.

In conclusion, the study emphasizes the importance of combining traditional methods with modern biotechnological approaches to ensure the reproduction and sustainable conservation of this emblematic species.

Ref. : Tesse R., Boutaleb F., Bahlaouan B., Brett-Crowther M., El Antri S., & Boutaleb N., 2025 - Micrografting and Other Regeneration Techniques for the Argan Tree (Argania spinosa): A PRISMA-Based Systematic Review and Meta-Analysis. Natural Built Social Environment Health 1(3). DOI :10.63095/NBSEH.25.180342

Posted by Jean-Paul Peltier.

[Jun 23, 2025] Non-native species diversity: Ten new species detected in a cumin field in southeastern Morocco

The article presents a list of ten non-native species recently identified in cumin crops in southeastern Morocco. These include Anthemis hyalina, Anthemis scariosa, Centaurea verutum, Carduus arabicus, Cota palaestina, Cota coelopoda, Hyoscyamus pusillus, Plantago exigua, Suchtelenia szovitsiana, and Silene coniflora. At this stage, most of these species are considered occasional exotics. However, Plantago exigua stands out due to its high invasive potential, spreading beyond cultivated areas. The article also provides essential data on the morphology, identification criteria, geographical distribution, and risk assessment associated with these newly detected species.

Ref. : Homrani Bakali H., Chatelain C. & Khamar H., 2025 - New non-native species recorded in cumin crop in southeastern region of Morocco. Botany Letters, DOI : 10.1080/23818107.2025.2506559 (18 Jun).

Posted by Jean-Paul Peltier.

[Mar 16, 2025] Santolina razaneae (Asteraceae), a new species for science and Morocco

Based on morphological characters, Santolina razaneae, a new Asteraceae species growing in the steppic habitats of eastern Morocco (Moulouya valley and High Plateaus), is described and illustrated. This species is distinguished from other Santolina species present in Morocco by its unique morphological traits, including elliptic leaflets and pinnate leaves with obtuse lobes, triangular, lacerate, and glabrous paleae, and florets with triangular, pale pinkish lobes. A key to the spontaneous Santolina species occurring in Morocco is provided.

Réf. : Homrani Bakali H., Chambouleyron M. & Leger J.-F., 2025 - Santolina razaneae (Asteraceae), a new steppic species from Morocco. Phytotaxa 693 (3) : 235–244. https://doi.org/10.11646/phytotaxa.693.3.4.

Posted by Jean-Paul Peltier.

Last modified on Thursday, October 16, 2025 at 16h33.