¿Qué es Astragalus wiesneri? Delimitando una nueva especie en la sección Anthylloidei

Here, we describe and illustrate a new alpine species of Astragalus sect. Anthylloidei from Iran. Astragalus wiesneri sp. nov., an interesting and rare species, is only known from the type locality in the Bul Mountain (near Eghlid city) in the southern Zagros Mountains. The new species is compared with close relatives, including A. nigrohirsutus and A. lalesarensis, which are also endemic to Iran. In addition, we assembled a dataset of nrDNA ITS sequences of 21 species (22 accessions) representing A. sect. Anthylloidei and ten species of other related spiny-cushion forming sections. Maximum likelihood methods and Bayesian Inference retrieved A. wiesneri sister to A. nigrohirsutus, a species growing in the same area as the new species. The description of A. wiesneri is presented along with a distribution map, some ecological information, field images, conservation status, and pertinent notes.Se describe e ilustra una nueva especie alpina de Irán, perteneciente a Astragalus sect. Anthylloidei. Astragalus wiesneri sp. nov., una especie hasta ahora desconocida, crece en las zonas altas del Monte Bul al sur de los Montes Zagros. La nueva especie se comparó con especies afines incluyendo A. nigrohirsutus y A. lalesarensis, también endémicas de Irán. Además del examen morfológico, se construyó una matriz de datos moleculares representando 21 especies (22 especímenes) de A. sect. Anthylloidei y 10 especies de otras secciones del género que incluyen arbustos almohadillados espinosos. Se realizaron análisis filogenéticos de secuencias de la región ITS del ADN ribosómico nuclear. Los análisis moleculares indican que A. wiesneri es hermana de A. nigrohirsutus, una especie con la que vive en simpatría. La descripción morfológica de A. wiesneri va acompañada de un mapa de distribución, información ecológica, imágenes de campo, estado de conservación y comentarios relevantes

Trade-off or coordination? Correlations between ballochorous and myrmecochorous phases of diplochory

The combination of two dispersal syndromes (diplochory) brings additional benefits to seeds, yet the relative costs and benefits of the two phases are poorly understood. Our goal is to provide the first quantification to test the long-standing assumption that there are trade-offs between the two phases in ballistic–ant diplochory. Dispersal investment data were empirically measured for 91 Euphorbiaceae species across different regions of the world. Dispersal distance data of ballochory (seed dispersal by explosion), myrmecochory (seed dispersal by ants) and diplochory was collated from the literature for 210 records (148 species from 44 families). The data were analysed using Model II regression, Kolmogorov–Smirnov test and t test, complemented by phylogenetic comparative approaches. Across diaspores of diplochorous species, the relative investment in myrmecochory increased more than that in ballochory. Fruit coat mass and elaiosome mass covaried in an allometric manner, regardless of seed mass. Diplochorous diaspores were significantly heavier than diaspores dispersed solely by ballochory. Dispersal distances of the two diplochorous phases were independent and comparable to that of sole ballochory or sole myrmecochory. Our results do not support a trade-off, but a coordinated dispersal strategy between the two diplochorous phases. Large diaspores may evolve diplochory to overcome dispersal difficulties in term of dispersal distance. As the most comprehensive study of ballistic–ant diplochory, our findings advance the understanding of the relative importance of the two phases in diplochory. A plain language summary is available for this article