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Aim: Understanding the historical biogeography of the Earth's oldest terrestrial lineages provides insights into lineage diversification in relation to plate tectonics, climate change and biome shifts at maximum timescales. We investigate the biogeography of an ancient arachnid family, dragon pseudoscorpions, which are found today in mesic (mostly temperate) forests on all continents except Antarctica and Europe, have potential origins on Pangea and comprise species with extremely limited dispersal capacities. We evaluate the respective role of continental vicariance (abiotic) and biome shifts (biotic) deep in time and unravel the evolutionary history of this ancient group. Location: Global. Taxon: Pseudotyrannochthoniidae (Arachnida: Pseudoscorpiones). Methods: Five loci were sequenced for 75 Pseudotyrannochthoniidae samples collected across the globe. A matrix was compiled comprising 106 terminals and ~8800 bp, and phylogenetic analyses were performed to uncover relationships. Divergence time and ancestral range estimation analyses were used to reconstruct historical biogeography. Results: Pseudotyrannochthoniidae was monophyletic with high support but relationships among genera did not reflect current taxonomy and instead showed geographical structuring. Pseudotyrannochthoniidae originated in East Asia during the Middle Triassic and began diversifying in the Early Cretaceous. Main Conclusions: Diversity and distributional patterns of dragon pseudoscorpions can be explained by the interplay of continental vicariance through Pangaean breakup, and biome shifts via the spread of temperate habitats in the Cretaceous and their ongoing distributional fluctuations. Pseudotyrannochthoniidae diversification began in the Early Cretaceous as they dispersed with temperate forests across the Northern Hemisphere. Cretaceous vicariance, followed by widespread Holarctic extinction in the Late Tertiary–Quaternary, created their disjunct distribution at northern latitudes. Northern and Southern Hemisphere lineages diverged as Gondwana and Laurasia rifted, and Gondwanan breakup resulted in Afrotropical/Indomalayan and Austral clades. Austral lineages spread with temperate forests, however, cooling caused their disappearance from Antarctica and led to disjunct distributions at low latitudes. [ABSTRACT FROM AUTHOR]

Abstract: Aim: To infer divergence times and historical biogeography of the cosmopolitan lycophyte family Lycopodiaceae. Location: Worldwide. Methods: We generated time‐calibrated phylogenies of the Lycopodiaceae based on six regions of chloroplast DNA using a node‐dating approach implemented in beast with eight fossil calibrations. To investigate effects of among‐lineage substitution rate heterogeneity on divergence time estimation, we compared the performance of two relaxed clock models: an uncorrelated lognormal clock model and a random local clock (RLC) model. The historical biogeography of the family was inferred using two Bayesian models implemented in BioGeoBEARS. Results: Divergence time estimates for major groups of the Lycopodiaceae obtained using the two substitution clock models differed substantially, and the RLC model was a better fit. The Lycopodiaceae crown group age is estimated to be late Devonian, and most deep divergence events date to the Carboniferous, with most extant species diversity accumulating during the Cenozoic. The timing of divergences of major clades in the Lycopodiaceae corresponds to the breakup of the Pangaean and Gondwanan supercontinents. Long‐distance dispersal events are relatively common, but generally do not appear to be followed by subsequent radiations. Main conclusions: Accounting for among‐lineage substitution rate heterogeneity improves divergence time estimates for the Lycopodiaceae. The family has a deep evolutionary history, and continent‐scale vicariance events in the Mesozoic appear to have been associated with major cladogenesis events, with long‐distance dispersal playing a relatively minor role. [ABSTRACT FROM AUTHOR]

Aim To explore the phylogenetics and historical biogeography of the dragonfly family Petaluridae (known as 'petaltails'), a relict dragonfly group with unique habitat and life history attributes. Location Australia, New Zealand, Japan, Chile and North America. Methods Using five mitochondrial and three nuclear gene fragments we recovered garli- part maximum likelihood and Bayesian phylogenetic hypotheses for 10 of the 11 extant petaltail species. Biogeographical patterns were analysed using Lagrange and interpreted through beast relaxed clock dating analysis. Results Petaluridae is monophyletic with an origin in the mid-Jurassic, c. 157 Ma. The family consists of two major clades: one with a Laurasian distribution containing the genera Tachopteryx and Tanypteryx, and another containing the genera Petalura, Phenes and Uropetala, distributed in Gondwanan remnants. Based on our beast molecular clock, these two clades separated c. 146 Ma. Species ages in Petaluridae range from c. 100 to c. 30 million years, with the majority of the species persisting for 70-75 million years. Analysis with Lagrange points to an origin for the family associated with New Zealand, with subsequent dispersal to other Gondwanan remnants (Australia and Chile) as well as Laurasia (eastern and western North America) and subsequent dispersal from western North America to Japan. Main conclusions The extant species of Petaluridae are extremely old, with most species persisting as independent lineages since the Jurassic. Our results suggest that New Zealand was close to the origin point in the Jurassic; one possibility is that Antarctica was at the centre of the petalurid distribution, based on Permian fossil evidence. Such long persistence for species is surprising, especially considering the specialized habitat required by petalurid larvae; unlike the majority of modern dragonflies, which spend their larval stage in ponds or streams, petaltails live in fen habitats. Petaltails also take multiple years to develop from egg to adult, another trait uncommon in modern dragonflies. Specialization in a species is normally associated with higher extinction rates; the petaltails appear to be an exception to this rule. [ABSTRACT FROM AUTHOR]