Plant Systematics and Evolution

Alban, Dorian M.; Biersma, Elisabeth M.; Kadereit, Joachim W.; Dillenberger, Markus S.

doi: 10.1007/s00606-021-01793-wpmid: N/A

Colobanthus (23 species) and Sagina (30–33 species) together are sister to Facchinia. Whereas Facchinia is distributed in western Eurasia, Colobanthus is almost exclusively distributed in the Southern Hemisphere, and Sagina is distributed in both hemispheres with the highest species diversity in western Eurasia. We examined: 1. Whether Sagina and Colobanthus are monophyletic sister genera, 2. Where the two genera originated and how many times dispersal between hemispheres occurred, and 3. Which colonization routes between hemispheres were taken. We reconstructed the phylogeny of Colobanthus and Sagina using nuclear ribosomal internal transcribed spacer (ITS) and two plastid spacers (cpDNA) of altogether 158 ingroup samples of 45 species, and performed molecular dating and ancestral area reconstructions. Sagina and Colobanthus were confirmed as monophyletic sister genera. Biogeographical reconstructions based on ITS and cpDNA showed that Sagina reached the Southern Hemisphere in Australasia or in Africa. For Colobanthus, patterns were less clear and less well-supported: ITS showed Australasia as the region of entry, but cpDNA implied that the Southern Hemisphere may have been entered in America. The extant distributions and the biogeographical histories of Colobanthus and Sagina show both similarities and dissimilarities. This illustrates that biogeographical histories, even of closely related and ecologically very similar lineages, can be highly idiosyncratic.

Contreras, Sergio; Landahur, Manlio; García, Karla; Latorre, Claudio; Reyers, Mark; Rethemeyer, Janet; Jaeschke, Andrea

doi: 10.1007/s00606-021-01800-0pmid: N/A

In the hyperarid Atacama Desert, water availability plays a crucial role in allowing plant survival. Along with scant rainfall, marine advective fog frequently occurs along the coastal escarpment fueling isolated mono-specific patches of Tillandsia vegetation. In this study, we investigate the lipid biomarker composition of the bromeliad Tillandsia landbeckii (CAM plant) to assess structural adaptations at the molecular level as a response to extremely arid conditions. We analyzed long-chain n-alkanes and fatty acids in living specimens (n = 59) collected from the main Tillandsia dune ecosystems across a 350 km coastal transect. We found that the leaf wax composition was dominated by n-alkanes with concentrations (total average 160.8 ± 91.4 µg/g) up to three times higher than fatty acids (66.7 ± 40.7 µg/g), likely as an adaptation to the hyperarid environment. Significant differences were found in leaf wax distribution (Average Chain Length [ACL] and Carbon Preference Index [CPI]) in the northern zone relative to the central and southern zones. We found strong negative correlations between fatty acid CPI and n-alkane ACL with precipitation and surface evaporation pointing at fine-scale adaptations to low moisture availability along the coastal transect. Moreover, our data indicate that the predominance of n-alkanes is reflecting the function of the wax in preventing water loss from the leaves. The hyperarid conditions and good preservation potential of both n-alkanes and fatty acids make them ideal tracers to study late Holocene climate change in the Atacama Desert.

Greimler, Josef; Temsch, Eva M.; Xue, Zhiqing; Weiss-Schneeweiss, Hanna; Volkova, Polina; Peintinger, Markus; Wasowicz, Pawel; Shang, Hui; Schanzer, Ivan; Chiapella, Jorge O.

doi: 10.1007/s00606-021-01796-7pmid: N/A

The grass Deschampsia cespitosa is a variable taxon out of which many varieties, subspecies and endemic species have been separated. In this paper, the variation in genome size (GS) and ploidy of this grass including several of its subspecies and two related species in Eurasia was investigated by flow cytometric (FCM) measurements. GS and ploidy data were also related to specific environments and reproduction mode. Ploidy levels found by FCM were confirmed by chromosome counts of diploid (2n = 26) and tetraploid (2n = 52) samples. Seminiferous (seed bearing) D. cespitosa was mainly diploid (GS between 3.754 and 5.438 pg/1C). GS variation in diploids showed a geographic pattern with a significant difference (H = 41,441, P < 0.001) between European (median = 4.377 pg) and Asian (median = 4.881 pg) accessions. Genome size (1C) in tetraploids ranged from 7.9426 to 9.0399 pg. Tetraploid seminiferous D. cespitosa was found mostly in disturbed habitats in western and southern Europe, while tetraploids in Asia were registered in wet Arctic habitats. Genome size (1C between 8.3278 and 8.8603 pg) of the pseudoviviparous plants (spikelets produce plantlets asexually) of wet habitats in central and northern Europe indicated tetraploidy. A putative triploid (GS 6.6817 pg) was detected in Iceland. Summing up, we found a high variation in GS on the geographic scale with significant regional differences in diploid D. cespitosa. Among the tetraploids, the asexually reproducing plants were bound to specific habitats, while the seminiferous plants showed a habitat preference similar to the diploids.

Mousavi, Sabereh S.; Mozaffarian, Valiollah; Mummenhoff, Klaus; Downie, Stephen R.; Zarre, Shahin

doi: 10.1007/s00606-021-01792-xpmid: N/A

Previous molecular phylogenetic investigations of Apiaceae tribe Pimpinelleae have focused primarily on its largest genus Pimpinella and its closest allies. The monophyly and phylogenetic placements of five Iranian genera of the tribe have not been addressed sufficiently (Aphanopleura, Demavendia, Haussknechtia, Psammogeton, and Zeravschania). To examine relationships, a nrDNA ITS matrix including 169 accessions representing 49 genera of Apiaceae (including 10 Iranian taxa not analyzed previously) and a cpDNA rps16 matrix containing 37 accessions representing 24 genera of the family, representing the greatest sampling to date of the aforementioned genera, were subjected to phylogenetic analyses using Bayesian inference and maximum parsimony methods. The trees obtained showed a close affinity among the examined species of Aphanopleura, Psammogeton and several species of Trachyspermum. Neither Aphanopleura nor Psammogeton resolved as monophyletic, and A. leptoclada allied with Pimpinella. The genera Demavendia, Haussknechtia and Zeravschania also comprised a well-supported clade, with Demavendia and Haussknechtia (in the ITS trees) arising from within a paraphyletic Zeravschania. To recognize monophyletic genera, one new combination is proposed in Pimpinella and six new combinations are proposed in Psammogeton. A broader circumscription of Zeravschania to include Demavendia and Haussknechtia may also be warranted, but must await further study.

Temraleeva, Anna; Krivina, Elena; Boldina, Olga

doi: 10.1007/s00606-021-01795-8pmid: N/A

Nannochloris-like green microalgae have evidently evolved by convergent evolution and are often unidentifiable by microscopy, including transmission electron microscopy (TEM). Their relatively simple morphology conceals an extremely high phylogenetic, physiological, and ecological diversity. The use of molecular tools has revolutionized algal diversity research, including the discovery of numerous new taxa. Strains ACSSI 104 and ACSSI 144 were isolated from solonetz and chestnut non-alkali soil, respectively (Volgograd region, Russia), in August 2014. Morphological and ultrastructural characteristics, a comparison of reproduction types and habitats, and the difference of the 18S rRNA gene and ITS2 secondary structure of the studied strains allowed us to propose a new genus—Edaphochloris A.Temraleeva, E.Krivina & O.Boldina, gen. nov. with type species—E. andreyevii A.Temraleeva, E.Krivina & O.Boldina, sp. nov. The new genus differed from the closely related Nannochloris-like genera through cell shape and size, chloroplast type, reproduction type, habitat, and value of genetic distances.

Bordbar, Firouzeh; Mirtadzadini, Mansour; Razafimandimbison, Sylvain G.

doi: 10.1007/s00606-021-01799-4pmid: N/A

The monospecific genus Aitchisonia (Rubiaceae), a suffrutescent plant endemic to Afghanistan, Iran, and Pakistan, was merged in the genus Plocama of the monogeneric tribe Putorieae sensu Backlund et al. (Spermacoceae alliance, subfamily Rubioideae). This decision was based on the phylogenetic placement of the specimen Rafei and Zangooei 25651 (FUMH) erroneously identified as Aitchisonia rosea in Plocama. This specimen was later correctly re-identified as Plocama dubia, rending the position of Plocama rosea (= Aitchisonia rosea) in Plocama (thus Putorieae) doubtful. We reconstructed a new phylogeny of Spermacoceae alliance based on trnL-F and nrITS sequence data and using the Bayesian method to: 1) assess the phylogenetic placement of P. rosea within Rubioideae, using new material from Iran; 2) pinpoint the phylogenetic positions of Plocama asperuliformis, P. crucianelloides, P. dezfulensis, P. ehrendorferi, P. kandaharensis, P. szowitsii, and P. vassilczenkoi; and 3) re-assess the monophyly of Plocama bruguieri and P. eriantha. The trnL-F and nrITS trees further support the monophyly of the Rubieae complex, but were not fully congruent. The trnL-F tree resolved Plocama rosea as sister to tribe Rubieae (including Kelloggia), while the nrITS tree was inconclusive. We described a new monogeneric tribe Aitchisonieae to accommodate P. rosea. Our nrITS analysis resolved Plocama crucianelloides in the Plocama Middle-Eastern clade and P. asperuliformis, P. dezfulensis, P. ehrendorferi, P. kandaharensis, P. szowitsii, and P. vassilczenkoi in the Plocama Central-Asian clade, both sensu Rincón-Barrado et al. The non-monophyly of P. bruguieri and P. eriantha is confirmed.

Ito, Yu; Yadav, Shrirang R.; Chang, Yuan Shiun; Tagane, Shuichiro; Li, Pan; Ohi-Toma, Tetsuo

doi: 10.1007/s00606-021-01797-6pmid: N/A

Nothapodytes (Icacinaceae) is a genus of seven to eleven evergreen or deciduous tree species distributed in tropical Asia from India to Japan. Nothapodytes nimmoniana sensu lato is the most widespread species of the genus, being reported sporadically throughout South Asia, Southeast Asia, Taiwan, and Japan’s southwest islands. Nothapodytes amamianus was recently described from Amami-oshima, Japan, the northeastern edge of this widespread species’ range. However, the phylogenetic distinction between these two species has yet to be explored. Here we present an analysis of molecular species delimitation to test the morphology-based taxonomic hypothesis currently used to differentiate the two species. The results clearly show that N. nimmoniana sensu lato comprises two species, one in India and the other in Taiwan and Japan, including N. amamianus, requiring a reassessment of the morphological traits hitherto used to define the former and distinguish it from the latter in East Asia. Based on the taxonomic history of the taxa and rules of nomenclature, the name N. nimmoniana is retained for the former. We propose a new combination, N. insularis, for the latter. Longitudinal intraspecific geographic structure is highlighted as an apparent indicator of further hidden diversity in India’s Western Ghats.

Butler, Hannah C.; Cozien, Ruth J.; Johnson, Steven D.

doi: 10.1007/s00606-021-01798-5pmid: N/A

Adaptation to pollinators can include the spatial arrangement of flowers on inflorescences. A brush-like arrangement of flowers has evolved in multiple plant families. The accessible rewards in these “brush flowers” are often utilized by both birds and insects, making it challenging to assess which are the main contributors to pollination. We investigated two such species, Scadoxus puniceus and S. membranaceus, by means of camera trapping, direct observations, and selective exclusion and controlled pollination experiments in order to determine the extent to which sunbirds contribute to their pollination. We found that flowers of S. puniceus are frequently visited by sunbirds, butterflies and honeybees, whereas those of S. membranaceus are rarely visited. Birds typically perch directly on the densely packed flowers of S. puniceus and pick up large, visible pollen loads on their beaks, heads and feet as they feed on nectar. The flowers of this species match the bills of the sunbirds in length, and the floral nectar properties are also consistent with specialisation for pollination by sunbirds. Butterflies feed on the nectar of S. puniceus, but seldom contact the reproductive structures, likely limiting their effectiveness for pollen transfer. Selective exclusion of larger visitors, including birds and butterflies, negatively affected fruit and seed set for both species. Controlled pollination experiments revealed that S. puniceus is self-incompatible, whereas S. membranaceus is self-compatible and can set fruit autonomously. This study reveals that these two paintbrush lilies which are considered to be closely related have divergent pollination and breeding systems despite sharing similar inflorescence architecture.

Sangvirotjanapat, Sunisa; Fér, Tomáš; Denduangboripant, Jessada; Newman, Mark F.

doi: 10.1007/s00606-021-01789-6pmid: N/A

A molecular systematic study of Globba section Nudae (Zingiberaceae) using ITS and matK sequences identifies three major clades, Globba subsection Nudae, G. subsection Mediocalcaratae and a new subsection, Globba subsection Pelecantherae, which is described here. The two species belonging in this subsection, Globba pelecanthera and Globba securifer, which are both new, are described. Rectangular anther appendages are reported in Globba for the first time. Evidence of hybridisation is given. The morphological characters of the flowers, which are likely to be important in pollination, are discussed.

Vasquez, Susana I.; Welker, Cassiano A. D.; Solís Neffa, Viviana G.; Peichoto, Myriam C.

doi: 10.1007/s00606-021-01801-zpmid: N/A

Saccharum s.l. comprises 35–40 species, including sugarcane (S. officinarum), and is distributed in the tropics and subtropics. The term “Saccharum complex” refers to four related genera: Saccharum, Erianthus s.l. (including E. sect. Ripidium, or Tripidium), Narenga, and Sclerostachya. Miscanthus and Miscanthidium are also closely related to this group. The delimitation of these genera is contentious and largely unresolved, with most species recognized under Saccharum. This study aimed to assess the morphological variation of the Saccharum complex, especially Saccharum s.s. and Erianthus s.l., and contribute to clarifying their generic circumscriptions. To accomplish this purpose, 31 exomorphological characters (17 qualitative and 14 quantitative) were analyzed using cluster (UPGMA) and discriminant analyses. The existence of significant differences among groups was analyzed by a one-way MANOVA. The morphological evidence clearly indicated three groups: (1) Saccharum s.s. from the Old World, (2) Tripidium + some species of Saccharum s.l. sometimes recognized as Narenga, Miscanthus, or Miscanthidium (all taxa from the Old World), and (3) Erianthus s.s. from the New World. The results support that the native species from the New World (Erianthus s.s.) are morphologically different from the species of Saccharum s.s. often cultivated, suggesting that Erianthus should be accepted as a genus distinct from Saccharum. For the species of Tripidium, we provide the morphological traits that distinguish them from Saccharum s.s. and Erianthus s.s. and revalidate the recent differential recognition postulated by molecular works.