Botany Letters, 2017, 164 (2)

Sommaire
:: A. S. BARFOD
Letter to the twenty-first century botanist – what is a flower? 4. Heterochrony – still an overlooked source of rapid morphological change in flowers?
Paru dans Botany Letters, 2017, 164 (2), pp. 105-109. Anglais
Abstract

This letter is meant to resume our series on the apparently simple question « What is a flower? », initiated in 2016. We have explored successively the general evo-devo debate (Nadot et Dodinet 2016), the multiple perceptions of the flower through the ages and society with an ethnobotanical viewpoint (Dodinet 2016), the flower as an evolutionary arms race (Selosse 2016) and the flower as a scent factory (Caissard and Baudino 2016). Here we visit the developmental phenomenon of heterochrony and discuss its putative evolutionary consequences for the diversification of the flower.

 
:: B. PUJOL, J. ARCHAMBEAU, A. BONTEMPS, M. LASCOSTE, S. MARIN & A. MEUNIER
Mountain landscape connectivity and subspecies appurtenance shape genetic differentiation in natural plant populations of the snapdragon (Antirrhinum majus L.)
Paru dans Botany Letters, 2017, 164 (2), pp. 111-119. Anglais
Abstract

We carried out a population genetic study of 14 populations (692 plants characterised at 23 microsatellite loci) of the plant species Antirrhinum majus L. (Plantaginaceae) across its geographic range. Our results showed that populations of A. majus are genetically differentiated and genetically diverse. We also found a small but statistically significant genetic differentiation between A. majus subspecies pseudomajus and striatum. Genetic diversity was higher in A. majus subspecies pseudomajus. Geographic distance and both latitudinal and longitudinal coordinates had no impact on genetic differentiation and diversity. We therefore did not find any signature of geographical range expansion. Mountains were found to play a role by affecting a small but statistically significant amount of genetic differentiation between populations. Our findings thereby suggest that most A. majus populations are reproductively isolated, and that the landscape and the evolutionary history of species affected their genetic variation.

 
:: N. M. G. ARDENGHI, W. P. ARMSTRONG & D. PAGANELLI
Wolffia columbiana (Araceae, Lemnoideae): first record of the smallest alien flowering plant in southern Europe and Italy
Paru dans Botany Letters, 2017, 164 (2), pp. 121-127. Anglais
Abstract

Wolffia columbiana (Colombia watermeal), a naturalized American neophyte, is recorded for the first time from southern Europe. Identification, distribution, invasion status, ecology, and pathways of introduction are presented. Furthermore, the potential invasive behaviour and impacts in the new growing site have been assessed with the EPPO prioritization process scheme for invasive alien plants.

 
:: M. E. UZUNHISARCIKLI, E. DOĞAN GÜNER, M. EKICI & F. ÖZBEK
Scrophularia clematidifolia: an enigmatic species from Turkey and its comparison with Scrophularia scopolii var. nusairiensis (Scrophulariaceae)
Paru dans Botany Letters, 2017, 164 (2), pp. 129-134. Anglais
Abstract

Scrophularia clematidifolia (Scrophulariaceae) has been rediscovered in Hatay, Turkey. It is closely related to Scrophularia scopolii var. nusairiensis, but it clearly differs from the other species in terms of leaves, inflorescence and fruit features. A taxonomic description, some photographs of the species, geographical distribution and habitat features are given. Additionally, seed macromicromorphology and pollen characteristics of S. clematidifolia are compared with the close relative species using light microscopy (LM) and scanning electron microscopy (SEM).

 
:: A. P. SUKHORUKOV, F. VERLOOVE, M. Á. ALONSO, I. V. BELYAEVA, C. CHAPANO, M. B. CRESPO, M. H. EL AOUNI, R. EL MOKNI, A. MAROYI, M. D. SHEKEDE, A. VICENTE, A. DREYER & M. KUSHUNINA.
Chorological and taxonomic notes on African plants, 2
Paru dans Botany Letters, 2017, 164 (2), pp. 135-153. Anglais
Abstract

The taxonomy of complicated native African taxa, Biscutella maritima (Brassicaceae) and annual species of Sesuvium (Aizoaceae) is discussed. The distribution of B. maritima is widened to the most of the coastal areas of NE Algeria and N Tunisia. Morphological differences with regard to other North African members of Biscutella ser. Biscutella are reported to facilitate the identification of B. maritima. We propose to accept four annual Sesuvium species (instead of the one previously accepted species, S. sesuvioides sensu amplissimo) with different distributions in Africa: S. digynum, S. hydaspicum, S. sesuvioides s.str. and S. nyasicum. A delimitation key based on morphological and carpological characters is provided. Lectotypes of S. digynum, S. digynum var. angustifolium, S. hydaspicum, S. nyasicum, Diplochonium sesuvioides (Sesuvium sesuvioides) and Trianthema polysperma (synonym of Sesuvium hydaspicum) are selected. Other discussed taxa belong to the alien elements of the flora. Atriplex semibaccata (Amaranthaceae-Chenopodiaceae) is reported as a new species for Cape Verde. Gaillardia × grandiflora (Asteraceae) is discovered as a new species for Africa found in Morocco. Prosopis velutina (Fabaceae) is collected for the first time in Northern Africa (Morocco). Mollugo verticillata (Molluginaceae) is recorded as a new species for DR Congo. Its morphology, including seed ornamentation, is discussed in reference to other similar-looking Molluginaceae. Incidence of American species Heterotheca subaxillaris (Asteraceae) in North Africa is discussed. Vernonanthura polyanthes (Asteraceae) is recorded as a naturalized invasive species in eastern Zimbabwe. It seems to be the first documented discovery of this ergasiophyte in Africa.

 
:: D. L. SZLACHETKO, M. KOLANOWSKA, R. MEDINA TREJO & M. LIPIŃSKA
New species of Maxillaria (Orchidaceae) from the Sibundoy valley, Colombia
Paru dans Botany Letters, 2017, 164 (2), pp. 159-170. Anglais
Abstract

Six new species of Maxillaria are described and illustrated based on material collected in southern Colombia. The taxonomic affinities of the new entities are discussed and information about their habitat and ecology is provided. Additionally, photographs of all new species are presented.

 
:: S. DEEPU, M. P. GEETHAKUMARY & A. G. PANDURANGAN
Typification of five names of Cinnamomum (Lauraceae)
Paru dans Botany Letters, 2017, 164 (2), pp. 171-176. Anglais
Abstract

This paper deals with the typification of five names of Cinnamomum Schaeffer: C. dubium Nees, C. gracile Hook.f. (non Miquel), C. perrottetii Meissner, C. travancoricum Gamble and C. wightii Meissner.

 
:: P. KUMAR, V. K. SINGHAL, A. R. ANDRADA & P. V. DE LOS A
Chromosome count and karyotype of two species of Clematis (Ranunculaceae)
Paru dans Botany Letters, 2017, 164 (2), pp. 177-181. Anglais
Abstract

Karyotype morphometric data of two species of the genus Clematis L., a cosmopolitan and diverse genus, were studied. Clematis flammula is a diploid with 2n = 16 chromosomes. It exhibits a gradual decrease in size of chromosomes from 14.83 (±3.6) μm to 7.58 (±3.65) μm. Its karyotype formula (2n = 2x = 16 = 10m + 6sm) differs from those of Clematis orientalis (2n = 4x = 32 = 18m + 8sm + 6st), which is in addition a tetraploid species. The intrachromosomal asymmetry (A1) indicates that C. flammula had the most symmetric karyotype A1 = 0.39 in comparison to C. orientalis (A1 = 0.96). The karyological data available in the literature for the genus have also been discussed against the backdrop of the present analysis. This is the first attempt to present the karyotype morphometric data for the tetraploid cytotype of C. orientalis from India.

 
:: B. VENTO, E. M. CARRETERO, G. MORENO & A. DUPLANCIC
Mineral contents in leaves of Morus alba L. (Moraceae) and Platanus hispanica Miller (Platanaceae) from the urban forests of centralwestern area of Argentina.
Paru dans Botany Letters, 2017, 164 (2), pp. 183-192. Anglais
Abstract

The returning of mineral contents and organic matter to the soil as litterfall is one of the most essential ecological process that contributes to the nutrient cycles and provides enough nutrients to plants for a healthy growth. The fallen leaves from urban forests of the cities of San Juan and Mendoza, Argentina are frequently collected especially during the autumn season with a loss of great quantity of litterfall every year. High amounts of nutrients and organic matter are exported from the urban ecosystem without completing the mineral nutrient cycle. The aim of this work is to evaluate the variation in foliar mineral and organic matter contents along seasons (spring, summer and autumn) for the two most abundant non-native species: Morus alba and Platanus hispanica located in the urban forests of the central-western part of Argentina, and the effect of the periodical leaf removal in urban areas. Differences in mineral and organic matter contents were found along the seasons. Foliar concentration losses follow the order of magnitude: N > Mg > P>K > Na. This research is a contribution to a more adequate understanding of the urban ecosystem patterns and dynamics, and it means to be helpful in the management and conservation practices of urban ecosystems.