Microcnemum coralloides (Chenopodiaceae-Salicornioideae): un ejemplo de las disyunciones intraespecíficas Este-Oeste en la región mediterránea

Microcnemum is a monotypic genus of Salicornioideae comprising rare, annual, hygrohalophytic herbs growing in hypersaline inland lagoons and salt pans. Microcnemum coralloides shows an East-West disjunction in the Mediterranean region: M. coralloides subsp. coralloides occurs in central and eastern Spain while M. coralloides subsp. anatolicum grows in Turkey, Syria, Armenia and Iran. We studied the phylogeny, biogeography and morphological differentiation of M. coralloides. Molecular analyses, using five western and eight eastern accessions of the species, were based on three different markers (nuclear ITS and plastid atpB-rbcL spacer and trnT/F region) analysed with Maximum Parsimony and Maximum Likelihood. Estimates of divergence times were calculated using a Likelihood Ratio Test (LRT) and the Penalized Likelihood (PL) method. The two subspecies can be clearly distinguished by their different seed testa surface. Other diagnostic characters were not found. The molecular data (ITS and ML analysis of the trnT/F region) indicate that M. coralloides subsp. coralloides originated from within M. coralloides subsp. anatolicum which implies an East Mediterranean origin and subsequent westward dispersal. Age estimates for the split of the two subspecies range from 2.8–0.5 million years ago. Considering the relatively low genetic differentiation and the low crown group age (0.7–0.1 mya) of M. coralloides subsp. coralloides in comparison to M. coralloides subsp. anatolicum we favour the hypothesis that the Iberian part of the species range was established during cold periods of the Early Pleistocene and that the range of the species was fragmented during a warmer period soon after its arrival in Iberia.Microcnemum es un género monotípico de Salicornioideae que consiste en hierbas higrohalófilas, anuales, raras, que crecen en cuencas endorréicas hipersalinas del interior y salares. Microcnemum coralloides muestran una disyunción Este-Oeste en la región mediterránea: M. coralloides subsp. coralloides aparece en el centro y el levante español, mientras que M.coralloides subsp. anatolicum crece en Turquía, Siria, Armenia e Irán. Estudiamos la filogenia, la biogeografía y la diferenciación morfológica de M. coralloides. Los análisis moleculares, empleando cinco adquisiciones occidentales y ocho orientales de la especie, se basaron en tres marcadores distintos (ITS nuclear, espaciadores plástidos atpBrbcL y región trnT/F) analizados con Máxima Parsimonia y Máxima Verosimilitud. Las estimaciones de tiempos divergentes se calcularon empleando una Prueba de Verosimilitud (LRT) y el método de Verosimilitud Penalizada. Las dos subspecies se distinguen claramente por la diferencia en la superficie de su envoltura. No se encontraron otras características de diferenciación. Los datos moleculares (ITS y análisis ML de la región trnT/F) indican que M. coralloides subsp. coralloides originó de dentro de M. coralloides subsp. anatolicum, lo cual implica un origen en el este del Mediterráneo y su posterior dispersión hacia el oeste. Las estimaciones de edad para la separación de las dos subespecies data desde hace 2,8 a 0,5 millones de años. En vista de la diferenciación genética, relativamente baja y la reducida edad del grupo terminal (0,7-0,1 millones de años) de M. coralloides subsp. coralloides en comparación con M. coralloides subsp. anatolicum, favorecemos la hipótesis de que la parte ibérica de la gama de la especie se estableció durante periodos fríos del Bajo Pleistoceno y que la gama de la especie se fragmentó durante un periodo más cálido no mucho después de su llegada a la Península

Tradeoffs in the evolution of plant farming by ants

Diverse forms of cultivation have evolved across the tree of life. Efficient farming requires that the farmer deciphers and actively promotes conditions that increase crop yield. For plant cultivation, this can include evaluating tradeoffs among light, nutrients, and protection against herbivores. It is not understood if, or how, nonhuman farmers evaluate local conditions to increase payoffs. Here, we address this question using an obligate farming mutualism between the ant Philidris nagasau and epiphytic plants in the genus Squamellaria that are cultivated for their nesting sites and floral rewards. We focused on the ants’ active fertilization of their crops and their protection against herbivory. We found that ants benefited from cultivating plants in full sun, receiving 7.5-fold more floral food rewards compared to shade-cultivated plants. The higher reward levels correlated with higher levels of crop protection provided by the ants. However, while high-light planting yielded the greatest immediate food rewards, sun-grown crops contained less nitrogen compared to shade-grown crops. This was due to lower nitrogen input from ants feeding on floral rewards instead of insect protein gained from predation. Despite this tradeoff, farming ants optimize crop yield by selectively planting their crops in full sun. Ancestral state reconstructions across this ant–plant clade show that a full-sun farming strategy has existed for millions of years, suggesting that nonhuman farmers have evolved the means to evaluate and balance conflicting crop needs to their own benefit

Phylogeny, biogeography and systematics of Dysphanieae (Amaranthaceae)

After a rather turbulent taxonomic history, Dysphanieae (Chenopodioideae, Amaranthaceae) were established to contain five genera, four of which are monospecific (Cycloloma, Neomonolepis, Suckleya, Teloxys) and geographically restricted, and the fifth genus, Dysphania, having a nearly worldwide distribution and comprising ca. 50 species. This study investigates the phylogeny, biogeography and taxonomy of Dysphanieae. We studied specimens from 32 herbaria to infer morphological differences and distribution areas of the species and sampled 121 accessions representing 39 accepted species of the tribe for molecular phylogenetic analyses. The molecular phylogeny tested generic relationships of the tribe and infrageneric relationships of Dysphania on the basis of two plastid DNA markers (atpB-rbcL spacer, rpl16 intron) and two nuclear ribosomal markers (ETS, ITS) and was also used for an ancestral area reconstruction with BioGeoBEARS. Three of the monospecific genera (Neomonolepis, Suckleya, Teloxys) form a basal grade and appear to be relictual lineages of the tribe, while Cycloloma is nested within Dysphania. The ancestral area reconstruction favors a widespread ancestry for Dysphanieae, and the relictual lineages in Asia (Teloxys) and North America (Neomonolepis, Suckleya) might be explained by a wide distribution across Beringia during the Late Oligocene/Early Miocene. Dysphania likely originated in North America; however, the simultaneous diversification into three major clades, an Asian/African, an American and an Australian/African clade, indicates a widespread ancestor at the crown node of Dysphania. Our taxonomic revision results in four accepted genera in Dysphanieae, Dysphania, Neomonolepis, Suckleya and Teloxys. The sectional subdivision for Dysphania is revised. We subdivide the genus into five sections, D. sect. Adenois (13 spp.), D. sect. Botryoides (10 spp.), D. sect. Dysphania (17 spp.), D. sect. Incisa (2 spp.) and D. sect. Margaritaria (4 spp.); three strongly deviating species remain unplaced and need further attention.Peer reviewe

Nothodissotis (Melastomataceae), a new genus from Atlantic Central Africa, including the new species N. alenensis from Equatorial Guinea

Based on morphological and phylogenetic evidence, a new genus of Melastomataceae (Melastomateae), Nothodissotis Veranso-Libalah & G.Kadereit, gen. nov., is described from Atlantic Central Africa. Nothodissotis is distinguished from other African Melastomateae genera by its calyx-lobes that are notched at apex and asymmetrical (vs. entire and symmetrical). Nothodissotis includes two species: the type species N. barteri (Hook.f.) Veranso-Libalah & G.Kadereit, comb. nov. (syn. Dissotis barteri Hook.f.), and the new species N. alenensis Veranso-Libalah & O. Lachenaud, sp. nov., described and illustrated here. Both species are restricted to open vegetation on rock outcrops within the forested region of Atlantic Central Africa. Nothodissotis barteri has a scattered distribution in Cameroon, Equatorial Guinea, Gabon and Príncipe Island, while N. alenensis is endemic to the Monte Alén massif in Equatorial Guinea, an area where N. barteri does not occur. Nothodissotis alenensis differs from N. barteri by its hypanthium bearing sessile appendages with penicillate hairs (vs. stalked stellate appendages) and its staminal appendages that are much smaller in antepetalous than in antesepalous stamens (vs. subequal in all stamens). The conservation status of both N. barteri and N. alenensis is assessed as Vulnerable in accordance with IUCN criteria

Inter- and intra-island speciation and their morphological and ecological correlates in Aeonium (Crassulaceae), a species-rich Macaronesian radiation

Background and Aims The most species-rich and ecologically diverse plant radiation on the Canary Islands is the Aeonium alliance (Crassulaceae). In island radiations like this, speciation can take place either within islands or following dispersal between islands. Aiming at quantifying intra- and inter-island speciation events in the evolution of Aeonium, and exploring their consequences, we hypothesized that (1) intra-island diversification resulted in stronger ecological divergence of sister lineages, and that (2) taxa on islands with a longer history of habitation by Aeonium show stronger ecological differentiation and produce fewer natural hybrids. Methods We studied the biogeographical and ecological setting of diversification processes in Aeonium with a fully sampled and dated phylogeny inferred using a ddRADseq approach. Ancestral areas and biogeographical events were reconstructed in BioGeoBEARS. Eleven morphological characters and three habitat characteristics were taken into account to quantify the morphological and ecological divergence between sister lineages. A co-occurrence matrix of all Aeonium taxa is presented to assess the spatial separation of taxa on each island. Key Results We found intra- and inter-island diversification events in almost equal numbers. In lineages that diversified within single islands, morphological and ecological divergence was more pronounced than in lineages derived from inter-island diversification, but only the difference in morphological divergence was significant. Those islands with the longest history of habitation by Aeonium had the lowest percentages of co-occurring and hybridizing taxon pairs compared with islands where Aeonium arrived later. Conclusions Our findings illustrate the importance of both inter- and intra-island speciation, the latter of which is potentially sympatric speciation. Speciation on the same island entailed significantly higher levels of morphological divergence compared with inter-island speciation, but ecological divergence was not significantly different. Longer periods of shared island habitation resulted in the evolution of a higher degree of spatial separation and stronger reproductive barriers.info:eu-repo/semantics/publishedVersio

Biogeography of the xerophytic genus Anabasis L. (Chenopodiaceae)

Aim Using the extremophile genus Anabasis, which includes c. 28 succulent, xerophytic C4 species, and is widely distributed in arid regions of Northern Africa, Arabia, and Asia, we investigate biogeographical relationships between the Irano-Turanian floristic region (ITfr) and its neighboring regions. We test whether the spread of arid and semi-arid biomes in Eurasia coincides with the biogeography of this drought-adapted genus, and whether the ITfr acted as source area of floristic elements for adjacent regions. Location Deserts and semi-deserts of Northern Africa, Mediterranean, Arabia, West and Central Asia. Methods Four cpDNA markers (rpL16 intron, atpB-rbcL, trnQ-rps16, and ndhF-rpL32 spacers) were sequenced for 58 accessions representing 21 Anabasis species. Phylogenetic relationships and divergence times were inferred using maximum likelihood and a time-calibrated Bayesian approach. To document the extant distribution of Anabasis, material from 23 herbaria was surveyed resulting in 441 well-documented collections used for the coding of eight floristic regions. Using this coded data, ancestral range was estimated using "BioGeoBEARS" under the DEC model. Results Anabasis originated during the Late Miocene and the ancestral range was probably widespread and disjunct between Western Mediterranean and the Irano-Turanian regions. Diversification started with two divergence events at the Miocene/Pliocene boundary (5.1 and 4.5 mya) leading to Asian clade I with ITfr origin which is sister to a slightly younger Asian clade II, which originated in the Western ITfr, and a Mediterranean/North African clade with an origin in the Western Mediterranean. Main conclusions Anabasis did not follow aridification and continuously expanded its distribution area, in fact its probably wide ancestral distribution area seems to have been fragmented during the very Late Miocene and the remnant lineages then expanded into neighboring arid regions. This genus supports the role of the ITfr as source area for xerophytic elements in the Mediterranean and Central Asia

Plant growth forms dictate adaptations to the local climate

Adaptive radiation is a significant driver of biodiversity. Primarily studied in animal systems, mechanisms that trigger adaptive radiations remain poorly understood in plants. A frequently claimed indicator of adaptive radiation in plants is growth form diversity when tied to the occupation of different habitats. However, it remains obscure whether morphological adaptations manifest as growth form diversity per se or as its constituent traits. We use the classic Aeonium radiation from the Canary Islands to ask whether adaptation across climatic space is structured by growth form evolution. Using morphological sampling with site-associated climate in a phylogenetic context, we find that growth forms dictate adaptations to the local environment. Furthermore, we demonstrate that the response of specific traits to analogous environments is antagonistic when growth forms are different. This finding suggests for the first time that growth forms represent particular ecological functions, allowing the co-occurrence of closely related species, being a product of divergent selection during evolution in sympatry.info:eu-repo/semantics/publishedVersio

How challenging RADseq data turned out to favor coalescent-based species tree inference. A case study in Aichryson (Crassulaceae)

Analysing multiple genomic regions while incorporating detection and qualification of discordance among regions has become standard for understanding phylogenetic relationships. In plants, which usually have comparatively large genomes, this is feasible by the combination of reduced-representation library (RRL) methods and high-throughput sequencing enabling the cost effective acquisition of genomic data for thousands of loci from hundreds of samples. One popular RRL method is RADseq. A major disadvantage of established RADseq approaches is the rather short fragment and sequencing range, leading to loci of little individual phylogenetic information. This issue hampers the application of coalescent-based species tree inference. The modified RADseq protocol presented here targets ca. 5,000 loci of 300-600nt length, sequenced with the latest short-read-sequencing (SRS) technology, has the potential to overcome this drawback. To illustrate the advantages of this approach we use the study group Aichryson Webb & Berthelott (Crassulaceae), a plant genus that diversified on the Canary Islands. The data analysis approach used here aims at a careful quality control of the long loci dataset. It involves an informed selection of thresholds for accurate clustering, a thorough exploration of locus properties, such as locus length, coverage and variability, to identify potential biased data and a comparative phylogenetic inference of filtered datasets, accompanied by an evaluation of resulting BS support, gene and site concordance factor values, to improve overall resolution of the resulting phylogenetic trees. The final dataset contains variable loci with an average length of 373nt and facilitates species tree estimation using a coalescent-based summary approach. Additional improvements brought by the approach are critically discussed

From cacti to carnivores: Improved phylotranscriptomic sampling and hierarchical homology inference provide further insight into the evolution of Caryophyllales

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/143660/1/ajb21069.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/143660/2/ajb21069_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/143660/3/ajb21069-sup-0002-AppendixS2.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/143660/4/ajb21069-sup-0005-AppendixS5.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/143660/5/ajb21069-sup-0001-AppendixS1.pd

A taxonomic backbone for the global synthesis of species diversity in the angiosperm order Caryophyllales

The Caryophyllales constitute a major lineage of flowering plants with approximately 12500 species in 39 families. A taxonomic backbone at the genus level is provided that reflects the current state of knowledge and accepts 749 genera for the order. A detailed review of the literature of the past two decades shows that enormous progress has been made in understanding overall phylogenetic relationships in Caryophyllales. The process of re-circumscribing families in order to be monophyletic appears to be largely complete and has led to the recognition of eight new families (Anacampserotaceae, Kewaceae, Limeaceae, Lophiocarpaceae, Macarthuriaceae, Microteaceae, Montiaceae and Talinaceae), while the phylogenetic evaluation of generic concepts is still well underway. As a result of this, the number of genera has increased by more than ten percent in comparison to the last complete treatments in the Families and genera of vascular plants” series. A checklist with all currently accepted genus names in Caryophyllales, as well as nomenclatural references, type names and synonymy is presented. Notes indicate how extensively the respective genera have been studied in a phylogenetic context. The most diverse families at the generic level are Cactaceae and Aizoaceae, but 28 families comprise only one to six genera. This synopsis represents a first step towards the aim of creating a global synthesis of the species diversity in the angiosperm order Caryophyllales integrating the work of numerous specialists around the world