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Ruthie Abeliovich and Edwin Seroussi

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Mehrshid Riahi and Farrokh Ghahremaninejad

Abstract

Molecular data have been increasingly used to study the phylogenetic relationships among many taxa, including scrophs. Sometimes they have provided phylogenetic reconstructions that are in conflict with morphological data leading to a re-evaluation of long-standing evolutionary hypotheses. In this paper, we review reports of the recent knowledge of the phylogenetic relationships within Scrophularieae (2011–2017). The results of these analyses led to the following conclusions. (1) Species of Scrophularia have undergone one or more Miocene migration events occurred from eastern Asia to the North America with subsequent long dispersal and diversification in three main directions. (2) Allopolyploid and aneuploid hybrid speciation between Scrophularia species can occur, so hybridization and polyploidy have an important role for history of diversification. (3) The ancestral staminode type for the genus Scrophularia seems to be a large staminode. (4) Monophyly of the genus Verbascum with respect to the genus Scrophularia is strongly supported. (5) Oreosolen, is not monophyletic, because all accessions of Oreosolen were nested within Scrophularia. We discuss methods of data collection and analysis, and we describe the areas of conflict and agreement between molecular phylogenies.

Open access

Nina Polchaninova, Galina Savchenko, Vladimir Ronkin, Aleksandr Drogvalenko and Alexandr Putchkov

Abstract

Being an essential driving factor in dry grassland ecosystems, uncontrolled fires can cause damage to isolated natural areas. We investigated a case of a small-scale mid-summer fire in an abandoned steppe pasture in northeastern Ukraine and focused on the post-fire recovery of arthropod assemblages (mainly spiders and beetles) and vegetation pattern. The living cover of vascular plants recovered in a year, while the cover of mosses and litter remained sparse for four years. The burnt site was colonised by mobile arthropods occurring in surrounding grasslands. The fire had no significant impact on arthropod diversity or abundance, but changed their assemblage structure, namely dominant complexes and trophic guild ratio. The proportion of phytophages reduced, while that of omnivores increased. The fire destroyed the variety of the arthropod assemblages created by the patchiness of vegetation cover. In the post-fire stage they were more similar to each other than at the burnt plot in the pre- and post-fire period. Spider assemblages tended to recover their pre-fire state, while beetle assemblages retained significant differences during the entire study period.