Bull 187 BULLETIN OF THE IRAQ NATURAL HISTORY MUSEUM Doostmohammadi et al. Bull. Iraq nat. Hist. Mus. (2024) 18 (1): 187-207. https://doi.org/10.26842/binhm.7.2024.18.1.0187 ORIGINAL ARTICLE RELICT SPECIES FROM AN AFRICAN ORIGIN IN SOUTHWEST ASIA: INSIGHTS INTO THEIR BIOGEOGRAPHY AND CONSERVATION Moslem Doostmohammadi*, Fatemeh Moein** and Firouzeh Bordbar* *Department of Biology, Faculty of Science, Shahid Bahonar University of Kerman, Kerman, Iran. **Plant and Animal Biology Department, Faculty of Science and Technology, University of Isfahan, Isfahan, Iran. Corresponding author: bordbar@uk.ac.ir Received: 11 Sept. 2023, Revised: 9 March 2024, Accepted: 10 Mar. 2024, Published: 20 June 2024 This work is licensed under a Creative Commons Attribution 4.0 International License ABSTRACT The Zagros Mountain range in western Iran is an area of species endemism within the Irano-Anatolian biodiversity hotspot. A couple of relict and morphologically isolated species have been reported for the Zagros Mountains, yet their distribution patterns in relation to the geological and climatic history of the region are not fully understood. Clinopodium kallaricum (Jamzad) Bordbar, 2019 (Lamiaceae), Hypericum dogonbadanicum Assadi, 1984 (Hypericaceae), and Iranoaster bachtiaricus (Mozaff.) Kaz. Osaloo, Farhani & Mozaff. 2018 (Asteraceae) are local endemic species restricted to Zagros with no clear affinities to the Irano-Turanian or other Northern Hemisphere temperate species. Previous studies suggested some afromontane relations for these species, beyond the Saharo-Sindian lowlands. Here, we provide dated phylogenies for these three species, to assess the most probable drivers behind this pattern of distribution. Our results represent that the split between these taxa and their relatives is not contemporaneous, implying different biogeographical histories. I. bachtiaricus originated in the Middle Miocene, while C. kallaricum and H. dogonbadanicum are relatively younger (late Miocene early Pliocene). The divergence of these taxa coincided with the major geological and climatic events of the Miocene, mainly the collision of the Afro-Arabia and Eurasia plates in 18-16 Mya and the aridification of the Sahara (started in 11-7 Mya), followed by a shift in the vegetation of the Sahara from subtropical/steppe to arid desert. The possible relict nature of these species is discussed, and the role of the Saharo-Sindian Region as a vicariant agent is highlighted, which could have subdivided formerly uniform populations and subsequently accelerated the allopatric speciation. Keywords: Clinopodium, Disjunctend distribution, Hypericum, Iranoaster, Relict species. INTRODUCTION The Irano-Turanian phytogeographical region is a vast area covering many highlands in south western Asia (Zohary, 1973). It is characterized by a high degree of continentality and a BULLETIN OF THE IRAQ NATURAL HISTORY MUSEUM Iraq Natural History Research Center & Museum, University of Baghdad https://jnhm.uobaghdad.edu.iq/index.php/BINHM/Home Copyright © Bulletin of the Iraq Natural History Museum Online ISSN: 2311-9799, Print ISSN: 1017-8678 https://doi.org/10.26842/binhm.7.2024.18.1.0187 https://orcid.org/0000-0003-1777-6676 https://orcid.org/0000-0003-1079-0707 https://orcid.org/0000-0002-0225-9812 mailto:bordbar@uk.ac.ir https://creativecommons.org/licenses/by/4.0/ https://jnhm.uobaghdad.edu.iq/index.php/BINHM/Home 188 Bull. Iraq nat. Hist. Mus. 18 (1): 187-207. Relict species from an African origin low amount of precipitation during the growing season (Djamali et al., 2011). This region harbors many species-rich plant lineages, such as Astragalus L., Cousinia Cass., Acantholimon Boiss., Eremurus M.Bieb., Silene L., and Nepeta L. Recent phylogeographical studies have confirmed that the Irano-Turanian Region was the center of origin and diversification of many plant lineages, which then radiated to other neighboring areas, including the Mediterranean region (some examples are: Font et al., 2009; Manafzadeh et al., 2014; Malik et al., 2017; Panahi, 2019; Žerdoner Calasan et al., 2021; Doostmohammadi et al., 2022). The Zagros Mountain range, which extends from the northeast of Iraq to the south of Iran, is situated in the central part of the Irano-Turanian Region. It is covered by the so-called “Kurdo-Zagrosian steppe-forest” composed of Quercus brantii Lindl. Woodlands mostly in the northern and western regions, Artemisia steppes in drier regions, and alpine vegetation in several high peaks (Zohary, 1973; Noroozi et al., 2020). The Zagros mountain is regarded as a separate unit (either in the form of a district, a sub-province, or a province) of the Irano- Turanian region, exhibiting strong and striking distribution patterns (Zohary, 1973; Takhtajan, 1986; Akhani, 2004, 2007) and is identified as an “area of endemism” having a high number of endemic species along with several endemic genera [such as Azilia Hedge & Lamond (Apiaceae), Ergocarpon C. C. Towns (Apiaceae), Haussknechtia Boiss. (Apiaceae), and Zeugandra P.H.Davis (Campanulaceae) (Noroozi et al., 2018, 2019)]. A high proportion of the Zagros plant species belong to the Irano-Turanian Region (Noroozi et al., 2020), while there are surprisingly some isolated and morphologically distinct species such as Hypericum dogonbadanicum Assadi (Hypericaceae), Clinopodium kallaricum (Jamzad) Bordbar (Lamiaceae), and Iranoaster bachtiaricus (Mozaff.) Kaz. Osaloo, Farhani & Mozaff. (Asteraceae), which are of high phytogeographical interest. These species have striking morphological differences with other Irano-Turanian species, and previous studies have proposed some African relations for them (Robson, 1987; Farhani et al., 2018; Bordbar and Mirtadzadini, 2019). Hypericum dogonbadanicum Assadi, 1984 (Hypericaceae) is a sub-shrubby chasmophyte species, described about 40 years ago from southwestern Zagros (Assadi, 1984). This species is clearly distinct from any other Hypericum species known from Iran, and Assadi (1984) suggested a relationship between H. dogonbadanicum and H. balearicum L. (sect. Psorophytom (Spach) Nyman) from the Balearic Islands in Spain, based on its habit, leaf margins, and stamen structure. Later, Robson (1987), criticized this idea, and based on several diagnostic morphological characters, demonstrated that H. dogonbadanicum belongs to sect. Campylosporus (Spach) R. Keller, with surprising close affinities to the Socotran endemic H. socotranum R. D. Good. Hypericum sect. Campylosporus is a group of about 10 shrubs and trees distributed in sub-tropical and tropical mountains of SW Arabia and eastern Africa [south of the Saharo-Sindian lowlands (Robson, 1985)], and the only species of this section growing above the Saharo-Sindian Region is H. dogonbadanicum. Clinopodium kallaricum (Jamzad) Bordbar 2019 (Lamiaceae) initially was introduced as a species of the genus Satureja L. (S. kallarica Jamzad, Jamzad, 1992), but was transferred to 189 BULLETIN OF THE IRAQ NATURAL HISTORY MUSEUM Doostmohammadi et al. Clinopodium simense group by Bordbar and Mirtadzadini (2019) based on morphological and molecular evidences. Members of C. simense group are morphologically very similar and apparently closely related to each other (Ryding, 2006). Clinopodium kallaricum is confined to the Zagros Mountains (north of the Saharo-Sindian region); while the other species of this group are distributed in the tropical high mountains of eastern Africa, south of the Saharo- Sindian regional zone. They are morphologically similar in a more or less creeping habit, with the sub-sessile glands only on the lower surface of the leaves and the diverging thecae (Bordbar and Mirtadzadini, 2019). The monotypic genus Iranoaster (Mozaff.) Kaz.Osaloo, Farhani & Mozaff., 2018 (Asteraceae), was recently established based on the enigmatic Aster bachtiaricus Mozaff., 1996 from western/central Zagros (Farhani et al., 2018). Farhani et al. (2018) argued that A. bachtiaricus is different from other Northern Hemisphere Aster species in “having thick woody rootstock, many heteromorphic leaves, solitary capitulum, 4-seriate phyllaries, reflexed ligulate flowers, and 1-seriate pappus” and their molecular phylogenetic analyses demonstrated that A. bachtiaricus is not closely related to the bulk of Aster and is placed between the basal lineages of the Southern Hemisphere and other Northern Hemisphere taxa of the tribe Astereae. Therefore, they treated this species as a separate, monospecific genus restricted to the Zagros Mountains. The co-occurrence of these isolated taxa in the Zagros Mountains brings up the question of whether they share a common evolutionary history. This research aimed to answer this question based on a dating analysis with addressing their phytogeographical aspects. Biogeographical analysis was also carried out for Clinopodium kallaricum (Jamzad) Bordbar, 2019 (Lamiaceae) as an example, to examine the hypothesis of the center of origin. Besides, the conservation importance of the Zagros Mountain in relation to save these remarkable species is highlighted. MATERIALS AND METHODS The geographical location of The Zagros Mountains within the Irano-Turanian Region in SW Asia is shown in Map (1). Data matrix preparation and node calibration: Three different sequence data sets were prepared for the three studied species and their allied species, which were then aligned and analyzed separately. All sequences were extracted from Genbank (Appendix). For combining different regions, they were concatenated together without partitioning. Hypericum dogonbadanicum Assadi, 1984 (Map 2): Sequences of ITS and trnL-trnF regions for 29 species of Hypericum and close genera were extracted from GenBank and concatenated. Our taxon sampling scheme covered all available sequences of members of H. sect. Campylosporus together with representatives from the major lineages of the genus Hypericum as recognized in recent molecular phylogenetic studies (Meseguer et al., 2013; Nurk et al., 2013). Two calibration points were used for Hypericum dogonbadanicum. A normal prior was assigned to the crown of Hypericaceae (the split between Eliea and the rest of the tree) with a 190 Bull. Iraq nat. Hist. Mus. 18 (1): 187-207. Relict species from an African origin mean of 65.2 Mya and a standard deviation of 11 obtained by Ruhfel (2011). To constrain the crown age of Hypericum, a lognormal prior was used with an offset of 33.9 Mya and a standard deviation of 0.7 based on Arbuzova (2005) and Meseguer et al. (2013). Iranoaster bachtiaricus (Mozaff.) Kaz.Osaloo, Farhani & Mozaff., 2018: A subset of sampling from previous studies (Brouillet et al., 2009; Farhani et al., 2018), including 23 species were extracted from Genbank for ITS and ETS regions and then combined for alignment. Our sampling strategy for dating analysis from among the huge tribe Astereae was based on covering major clades of the tribe (from both northern and southern Hemisphere lineages), according to previous phylogenetic studies (Brouillet et al., 2009; Farhani et al., 2018). Nodes were calibrated assigning a normal distribution with the mean of 38.68 million years as the secondary calibration and a standard deviation of 2.1 for the split between the tribes Astereae and Anthemideae according to Panero and Crozier (2016). Clinopodium kallaricum (Jamzad) Bordbar, 2019 (Map 3): A total of 68 species from Clinopodium and related genera were sampled from Genbank for dating analysis. DNA sequences of the nuclear region (ITS) and two chloroplast regions (matK and trnL-trnF) were combined for alignment. Clinopodium is a non-monophyletic group (Bräuchler et al., 2010; Bordbar and Mirtadzadini, 2019), and our sampling covered all main sub-clades and lineages of this genus together with other closely related genera. A node prior was calibrated for the most recent common ancestor (MRCA) of Acinos Mill. and Ziziphora L. (15.398 Mya with a SD of 2.8) (Rose et al., 2022), with a normal distribution. Sequence alignments and divergence time estimates: Each data set was aligned using MAFFT (Multiple Alignment using Fast Fourier Transform) v.6.0 (Katoh and Toh, 2008) with manual adjustment. The BEAST.XML input files were generated using BEAUTi v 1.10.4 and divergence times were estimated using BEAST v 1.10.4, (Suchard et al., 2018). Rate evolution was modeled in an uncorrelated lognormal relaxed clock framework (Drummond et al., 2006), and priors for the branch rate were assumed to be a Yule process under an HKY substitution model. The BEAST analyses were performed with two independent runs of Markov Chain Monte Carlo each for 10 million generations, sampling every 200 generations. The convergences of the chains and estimated sample sizes (ESSs) were confirmed to be sufficiently high (>200) in Tracer v 1.7.1 (Rambaut et al., 2014). Tree Annotator v 1.10.4 was used to find the maximum clade credibility reporting median node ages after discarding the first 10% of the generations as burn-in. Ancestral area reconstruction: The ancestral area of Clinopodium kallaricum was estimated based on the molecular dated tree generated in BEAST. The ancestral area of the tree species was estimated based on three models: the dispersal extinction-cladogenesis (DEC), the likelihood model (DIVA-LIKE) model, and the BAYAREA-LIKE model. For each model, we tested the additional parameter “j” as well (Matzke, 2014). The j parameter represents the relative pre_event weight of the founder event. The best model was selected based on the AIC scores. Considering the patterns of distribution and endemism, we categorized the seven geographical regions. A (East Asia), B (Euro-Siberian Region), C (Mediterranean Region), D 191 BULLETIN OF THE IRAQ NATURAL HISTORY MUSEUM Doostmohammadi et al. (South-west Asia), E (North Africa), F (Southern America), and G (East and Central Africa). The BioGeoBEARS package in R was used to conduct the analysis (Matzke, 2013). RESULTS The phylogenetic reconstructions by Beast analysis and based on limited sampling in the present study, are to a large extent, congruent with previous comprehensive phylogenetic studies on Hypericum (Meseguer et al., 2013; Nurk et al., 2013), Clinopodium (Bräuchler et al., 2010; Bordbar and Mirtadzadini, 2019), and the tribe Astereae (Brouillet et al., 2009; Farhani et al., 2018) and are therefore reliable. Molecular clock calculations indicated different divergence times for the three species. Based on the dating analysis, Iranoaster bachtiaricus diverged from its close species in about 17.1 Mya (95% HPD; 11.01–23.51) (Diag. 1). Our Beast analyses confirmed the previous studies, suggesting the intermediate position of I. bachtiaricus between Southern Hemisphere lineages and temperate Northern Hemisphere genera (Farhani et al., 2018; Jafari et al., 2015). Clinopodium kallaricum assembled in a monophyletic sub-clade together with other members of C. simense group, confirming previos studies (Bordbar and Mirtadzadini, 2019) (Diag. 2). The estimated divergence age of C. kallaricum is 4.9 Mya (95% HPD; 2.2–8.51). Hypericum dogonbadanicum represents a phylogenetic position between the African clade of H. revolutum Vahl and some northern Hemisphere (mostly East Asian) species, including H. ascyron L., H. monogynum L. and H. elatoides R.Keller (Diag. 3). It was diverged from the later three species in 8.03 Mya (95% HPD; 4.52–12.25), and the divergence age (stem age) of their clade (composed of H. dogonbadanicum and the three mentioned species) is about 10.48 Mya (95% HPD; 6.65–15.25). Our result of biogeographical analysis for Clinopodium kallaricum and related species showed that DEC (dispersal extinction cladogenesis) is the best model for explaining of Clinopodium biogeographical history. Based on the biogeographical result (Diag. 4). Clinopodium clade and allied species have had widespread distribution following the vicariance of East Asia and the Afrian clade about 8 Mya. Another vicariance event occurred about 5 Mya between Africa and Southwest Asian (Clinopodium kallaricum) species. 192 Bull. Iraq nat. Hist. Mus. 18 (1): 187-207. Relict species from an African origin Map (1): Phytogeographical subdivisions of SW Asia, according to Leonard (1988-1989) IT: Irano-Turanian Region with its sub-regions designated by numbers 1 to 4, ES: Euro-Siberian, M: Mediterranean, SS: Saharo-Sindian, AC: Central Asiatic. The dashed line outlines the Zagros Mountain range in the west of Iran. Map (2): General distribution of Hypericum sect. Campylosporus (based on Robson, 1985 and Assadi, 1984). Triangle and inset photo indicate H. dogonbadanicum. [Dashed line represents the Saharo-Sindian regional zone]. 193 BULLETIN OF THE IRAQ NATURAL HISTORY MUSEUM Doostmohammadi et al. Map (3): General distribution of Clinopodium simense species group (based on Ryding (2006) and Bordbar and Mirtadzadini (2019). Triangle and inset photo indicate C. kallaricum. Dashed line represents the Saharo-Sindian regional zone. Diagram (1): Dated phylogenetic tree of tribe Astereae retrieved from BEAST. Estimated divergence age values are represented for each node. 194 Bull. Iraq nat. Hist. Mus. 18 (1): 187-207. Relict species from an African origin Diagram (2): Chronogram of Clinopodium and related genera inferred from BEAST. Dating values are represented above nodes. Diagram (3): Dated phylogenetic tree of Hypericum inferred from BEAST analysis. Divergence ages are represented for each node. 195 BULLETIN OF THE IRAQ NATURAL HISTORY MUSEUM Doostmohammadi et al. Diagram (4): Ancestral area estimation of the Clinopodium kallaricum and allied species based on the DEC model. Single capital letters indicate the different biogeographic units used in this study. Mixed letters represent combinations of units. The units next to species names represent the current geographic range of each species. The black arrow shows the split node of Clinopodium kallaricum from the African Clinopodium species. DISCUSSION Phylogeography: Our dating results represent that the divergence times of these three taxa are not contemporaneous, suggesting that their distributions are ruled by at least two 196 Bull. Iraq nat. Hist. Mus. 18 (1): 187-207. Relict species from an African origin geological/climatic events. Tribe Astereae has been proposed to have originated in the southern hemisphere (most probably in South Africa), and then dispersed to other temperate areas of the northern hemisphere (Brouillet et al., 2009; Mandel et al., 2019). As mentioned before, I. bachtiaricus represents an intermediate position between the sothern and northern Hemisphere genera (Diag. 1). The divergence time of I. bachtiaricus from its relatives in the early Miocene (about 17 Mya) coincides with the age of the Gomphotherium land bridge, which was created following the first collision of the Afro-Arabia and Eurasia plates (Map 4a). This land bridge disappeared in the middle Miocene (16-14 Mya) following the re-opening of the seaway between the Mediterranean and Indian Ocean (Map 4b; Rögl, 1999). It is therefore likely, that the ancestors of I. bachtiaricus could have migrated to western Iran through the first connection between Afro-Arabia and Eurasia and were subsequently left isolated in the Zagros Mountains after the re-opening of the sea between the Mediterranean and Indian Ocean. In addition, the major uplift of the Zagros Mountains took place in 15-12 Mya (Mouthereau et al., 2012), which is another factor that could be responsible for the geographical isolation of this species. Map (4): Tectonic movements in the Miocene. A: first collision of Afro-Arabia to Eurasia plates and formation of the Gomphotherium land bridge, represented by the arrow, B: re-opening of a seaway between the Mediterranean and Indian Oceans. Triangles represent the Zagros Mountains. (Based on Rögl, 1999). Regarding Hypericum dogonbadanicum, our dated phylogenetic tree represents that it is assembled in a sub-clade with three Northern Hemisphere species. This sub-clade diverged from its African ancestor in about 10.4 Mya. Likewise, the split of Clinopodium kallaricum from its African relative dates back to about 4.9 Mya. It was inferred from the biogeographical analysis that the ancestor of Clinopodium kallaricum extended across eastern Africa to the late Miocene (Diag. 4). The divergence ages of both species in the late Miocene were probably governed by the same eco/geographical forces. It was formerly believed that the Sahara Desert is about 2-3 My old (Kroepelin, 2006). However, new findings suggest that the aridity of northern Africa and the creation of the Sahara Desert were triggered much earlier, in 11-7 Mya in the late Miocene, due to the shrinkage of Tethys Sea (Zhang et al., 2014). At the end of the Messinian salinity crisis (5.33 Mya), the aridity of the Sahara and the Arabian Peninsula intensified (Colin et al., 2008), which had a great impact on the diversification of plant species, acting as a vicariant agent that divided formerly widely 197 BULLETIN OF THE IRAQ NATURAL HISTORY MUSEUM Doostmohammadi et al. distributed populations north and south of this region (Zhang et al., 2014; Chen et al., 2014). Therefore, relict species of C. kallaricum and H. dogonbadanicum in the west of Iran are most probably the result of allopatric speciation in isolated populations above the Saharo-Sindian region. Another round of uplift of the Zagros Mountains has taken place about 5 Mya (Axen et al., 2001; Mouthereau et al., 2012), which could have intensified the isolation of these species. The role of the Saharo-Sindian region as a geographical barrier has been previously demonstrated in animals as well. It has been shown that the only species of elephant shrews north of the Sahara (Elephantulus rozeti) split from other species south of the Sahara due to the aridification and vegetation change in north Africa (Douady et al., 2003). In addition to this species, there is another surprising biological link between Africa and SW Iran in the genus Pteraulax (Afrotropical diptera), with all species restricted to southern Africa while P. oldroydi resides in the western foothills of the Zagros Mountains (Abbassian-Lintzen, 1966). On the opposite direction, the migration barrier of the Saharo-Sindian Region, also blocked plant species dispersal from the Irano-Turanian region into Africa. One example is the genus Pterocephalus (Caprifoliaceae), with a major distribution in the Mediterranean and Irano- Turanian regions, and one species, P. frutescens Hoscht, in the east African high mountains (Mayer and Ehrendorfer, 2000). In addition, expansion of the Saharo-Sindian lowlands pushed cold adapted Irano-Turanian species to higher elevations, which could lead to allopatric speciation in the sky islands of southern Iran (Doostmohammadi et al., 2018). The evidence from this study points towards the idea that the Saharo-Sindian region has had a major role in diversifying of life in mountainous areas around this region, both on its northern and southern sides. Conservation aspects: As an area of endemism within the Irano-Anatolian biodiversity hotspot, the Zagros mountain range harbors a rich diversity of plant species with a high rate of endemism (Noroozi et al., 2018). This diversity mostly belongs to some super diverse Irano- Turanian genera such as Astragalus, Acantholimon, Allium, Cousinia, Centaurea, and Dionysia, which diversified not only in the Zagros but also throughout the highlands of the Iranian plateau, with a higher endemicity in alpine elevations. The roles of the geological events of Zagros in the diversification of some of these genera are highlighted in recent studies (Bagheri et al., 2017; Moharrek et al., 2019; Doostmohammadi et al., 2022). Along with this recently diversified species (neo-endemics), there are also some relict, paleo- endemic species in the Zagros Mountains. All three studied species are local endemics in western/central Zagros with small population sizes and limited areas of occupancies, which rank them as threatened species. Clinopodium kallaricum and H. dogonbadanicum are assessed as Critically Endangered (CR), according to criterion B of the IUCN red list categories, representing 8 and 11.703 km2 of AOO’s and 2.589 and 14.382 km2 of EOO’s, respectively. Iranoaster bachtiaricus is assessed as data deficient (DD), since it is known only based on the type collection. Moreover, the Zagros Mountain was a refugia for some Euro- Siberian species (e.g. Pterocarya fraxinifolia (Poir.) Spach, Zelkova carpinifolia (Pall.) K. Koch and Quercus castaneifolia Pant (Zohary, 1973; Akhani and Salimian, 2003; Uzun and Khedir Galalaey, 2022), which, together with several endemic genera, highlights the need for 198 Bull. Iraq nat. Hist. Mus. 18 (1): 187-207. Relict species from an African origin a proper conservation strategy throughout this unique mountain range, harboring the largest oak forests in the Middle East. Table (1): Details of specimens of Hypericum and allies included in this study, including GenBank accession numbers. Taxa ITS trnL-trnF Eliea_articulata KC709409.1 KC709111.1 Vismia_glaziovii KC709410.1 KC709112.1 Harungana_madagascariensis KC709362.1 KC709062.1 Hypericum_elodes KC709393.1 KC709095.1 Hypericum_aegypticum KC709391.1 KC709091.1 Hypericum_scopulorum KC709395.1 KC709097.1 Hypericum_boreale KC709374.1 KC709074.1 Hypericum_crux-andreae KC709399.1 KC709101.1 Hypericum_hookerianum FJ694205.1 KC709148.1 Hypericum_hircinum KC709365.1 KC709065.1 Hypericum_coris KC709320.1 KC709011.1 Hypericum_reflexum KC709382.1 KC709081.1 Hypericum_quartinianum KC709428.1 KC709129.1 Hypericum_roeperianum KC709429.1 KC709131.1 Hypericum_revolutum KC709425.1 KC709046.1 Hypericum_bequaertii KC709426.1 KC709128.1 Hypericum_dogonbadanicum HE653454.1 KC709114.1 Hypericum_socotranum KC709394.1 KC709096.1 Hypericum_balfourii KC709397.1 KC709099.1 Hypericum_synstylum KC709304.1 KC708999.1 Hypericum_elatoides HE653456.1 KC709157.1 Hypericum_ascyron KC709330.1 KC709021.1 Hypericum_monogynum MH711394.1 KC709156.1 Hypericum_longistylum KC709445.1 KC709153.1 Hypericum_geminiflorum HM162838.1 KC709000.1 Hypericum_henryi KC709448.1 KC709159.1 Hypericum_forrestii FJ694202.1 KC709149.1 Hypericum_lancasteri KC709444.1 KC709161.1 Hypericum_wilsonii HE653658.1 - Table (2): Details of specimens of tribe Astereae included in this study, including GenBank accession numbers. Taxa ITS ETS Nardophyllum_bryoides DQ479114.1 DQ479137.1 Felicia_minima FJ457935.1 - Chrysocoma_ciliata FJ457941.1 - Psychrogeton_alexeenkoi LC027403.1 LC387698.1 Aster_tataricus FJ539125.1 JN543749.1 Psychrogeton_amorphoglossus LC027404.1 LC387702.1 Mairia_hirsuta FJ457929.1 - Llerasia_lindeni DQ479110.1 JQ042789.1 Pteronia_glomerata FJ457942.1 - Galatella_litvinovii LC027393.1 LC387684.1 199 BULLETIN OF THE IRAQ NATURAL HISTORY MUSEUM Doostmohammadi et al. Chrysopsis_mariana GQ892729.1 - Erigeron_acris ON527430.1 LC387676.1 Erigeron_hyrcanicus LC027390.1 LC387681.1 Neobrachyactis_roylei LC027400.1 LC387694.1 Heteropappus_altaicus KJ711876.1 LC387690.1 Aster_alpinus MH398798.1 LC387659.1 Symphyotrichum_novi-belgii EU781308.1 JN315950.1 Lessingia_virgata AF251624.1 AF251682.1 Kalimeris_longipetiolata JN315936.1 JN315960.1 Iranoaster_bachtiaricus LC027374.1 LC387661.1 Chrysanthemum_indicum EF577298.1 JN315964.1 Achillea_millefolium KR150185.1 - Chrysanthemoides_monilifera FJ861492.1 - Table (3): Details of specimens of Clinopodium and allies included in this study, including GenBank accession numbers. Taxa ITS trnl-trnf matK Acinos alpinus AY227141 AY506594 Blephila cilata MK585131 GU381580 GU381743 Bystropogon canariensis AY506634 - GU381726 Bystropogon origanifolius GU381409 GU381565 GU381727 Bystropogon plumosus AY704586 - - Bystropogon wildpretii AY704584 - - Bystropogon_puncatus AY704582 -- - Clinopodium aascendens - - AY840152 Clinopodium abyssinicum GU381403 GU381548 GU381710 Clinopodium alpinum - AY840180 AY840145 Clinopodium ashei DQ667237 - - Clinopodium atlanticum - GU381531 GU381697 Clinopodium axillare DQ017565 - - Clinopodium barosmum GU381393 - GU381683 Clinopodium betulifolium - GU381532 GU381698 Clinopodium brownei GU381426 GU381593 GU381593 Clinopodium caricum - KX38187 - Clinopodium caroliaunum - - GU381748 Clinopodium chinense - - KX526668 Clinopodium coccineum F369164 GU381585 AY840150 Clinopodium creticum - GU381533. AY840175 Clinopodium cylindristachys DQ0171562 - - Clinopodium dalmaticum JQ669340 - - Clinopodium darwini - GU381601 - Clinopodium debile - GU381530 GU381696. Clinopodium discolor - GU381539. - Clinopodium douglasii JQ669081 JQ669026 - Clinopodium grandiflorum GU012002 - KX526666 Clinopodium graveolens - - GU381667 Clinopodium hydaspidis GU381391 GU381515 GU381681 200 Bull. Iraq nat. Hist. Mus. 18 (1): 187-207. Relict species from an African origin Clinopodium kallaricum GU381539. MK680006 - Clinopodium klimandschari - GU381558 GU381721 Clinopodium macrostemum JQ669083 385720694 - Clinopodium molle - KX381819 - Clinopodium myrianthum GU381405 - - Clinopodium nanum GU381385 - GU381666 Clinopodium nepalense - - GU381680 Clinopodium nepeta - GU381534 AY840151 Clinopodium paradoxum GU381402 GU381543 GU381706 Clinopodium piperitum GU381388 GU381511 GU381677 Clinopodium polycephalum - - GU381701 Clinopodium revolutum GU381436 GU381609 AY840170 Clinopodium robustum GU381404 GU381553 GU381716 Clinopodium simense GU381407 GU381559 GU381722 Clinopodium suavelens - - GU381665. Clinopodium taxifolium JQ669084 385720695 - Clinopodium thymifolium JQ669121 62002162 AY840162 Clinopodium troodi - - GU381671 Clinopodium umbrosum - GU381537 GU381700 Clinopodium vimineum - - GU381760 Clinopodium vulgare JQ669085 MG225194 Clinopodium wardii GU381392 GU381516 - Clinopodiumum uhligi GU381406 GU381561 GU381724 Conradina grandiflora - AY943442 AY943512 Hedeoma martirensis GU381428 GU381596 Hoehnea epilobioides - - GU381731 Ziziphora clinopodioides GU381386 GU381508 GU381756 CONCLUSIONS The Saharo-Sindian region, as a major geographical feature of North Africa and the Arabia, and its ecological changes during that time, have had a considerable impact on plant diversification in the surrounding mountainous areas, both on its northern and southern sides. As shown here, the Saharo-Sindian region acted as a vicariant agent, which resulted in the allopatric speciation of several isolated species in the Zagros Mountains in the west of Iran. 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(2024) 18 (1): 187-207. من أصل أفريقي في جنوب غرب آسيا: رؤى حول جغرافيتها االحيائية االثريةاألنواع والحفاظ عليها *ردبارفيروزة ب فاطمة معين** و ،مسلم دوست محمدي* * .، كلية العلوم، جامعة الشهيد باهنر كرمان، كرمان، إيرانعلوم الحياةقسم * والتكنولوجيا، جامعة أصفهان، قسم بيولوجيا النبات والحيوان، كلية العلوم ** .إيران أصفهان، 20/6/2024، النشر: 3/10/2024القبول: ،9/3/2024املراجعة: ، 11/9/2023االستالم: الخالصة تعد سلسلة جبال زاغروس في غرب إيران منطقة توطن األنواع ضمن نقطة التنوع مظهريامن األنواع األثرية واملعزولة األناضولية. تم اإلبالغ عن اثنين-البيولوجي اإليرانية روس، إال أن أنماط توزيعها فيما يتعلق بالتاريخ الجيولوجي واملناخي كفي جبال زا و االنواع التالية: .للمنطقة ليست مفهومة بالكامل Clinopodium kallaricum (Jamzad) Bordbar, 2019 (Lamiaceae) Hypericum dogonbadanicum Assadi, 1984 (Hypericaceae) Iranoaster bachtiaricus (Mozaff.) Kaz. Osaloo, Farhani & Mozaff, 2018 (Asteraceae) مستوطنة محلًيا مقتصرة على وسط غرب زاكروس وال تظهر ارتباطات واضحة هي انواع الطورانية أو األنواع املعتدلة في نصف الكرة الشمالي. وقد أشارت -اإليرانية مع األنواع والجزيئية السابقة إلى وجود بعض العالقات األفريقية الجبلية لهذه املظهريةالدراسات في هذه الدراسة، تم تقديم األنواع، بعيًدا عن األراض ي املنخفضة الصحراوية السندية. واع الثالثة، لتقييم الدوافع األكثر احتماال وراء هذا النمط من سالالت مؤرخة لهذه األن أن االنقسام بين هذه هذه الدراسة الى إليها توزيع. وتمثل النتائج التي توصلتال مختلف يشير إلى ان التاريخ االحيائي و الجغرافي ، مماليس معاصرا و قريباتها االصنوفات 207 BULLETIN OF THE IRAQ NATURAL HISTORY MUSEUM Doostmohammadi et al. في العصر امليوسيني األوسط، في حين أن Iranoaster bachtiaricusاذ نشأ . لكل منها C. kallaricum و H. dogonbadanicum أوائل أصغر نسبًيا )أواخر العصر امليوسيني و قد تزامنت انقسامات هذه األجناس مع األحداث الجيولوجية و العصر البليوسيني(. -18مع أوراسيا قبل عربية -واملناخية الرئيسية في امليوسين، مثل تصادم صفيحتي أفرو 7-11الصحراء الكبرى بسبب انكماش بحر تيثس )بدأ قبل و قحلمليون سنة 16 مليون سنة( تاله تحول في الغطاء النباتي للصحراء الكبرى من شبه االستوائي/السبهي إلى الصحراء الجافة. تمت مناقشة الطبيعة األثرية املحتملة لهذه األنواع، وتم تسليط ور منطقة الصحراء السندية كعامل بديل، والذي كان من املمكن أن الضوء على د يقسم مجموعات سكانية موحدة سابًقا وبالتالي تسريع عملية االنتواع املتباين.