DOI: 10.3897/asp.83.e138238

Authors: Mattia Ragazzini, Roy M. J. C. Kleukers, Luc Willemse, Baudewijn Ode, Lara-Sophie Dey, Oliver Hawlitschek

Abstract: The Mediterranean Basin, recognized as a global biodiversity hotspot, harbors a remarkable diversity of grasshoppers, katydids, and crickets, many of which are endemic and potentially contain cryptic lineages. In this study, we generated a comprehensive dataset comprising 1,441 barcodes from 270 identified species within the Ensifera and Caelifera suborders. These were combined with existing data to form a dataset of 2,606 barcodes representing 351 species. We employed Maximum Likelihood (ML) topology reconstruction and applied five species delimitation methods (BIN, ABGD, ASAP, GMYC, and PTP) to detect potential incongruences between Operational Taxonomic Units (OTUs) and existing taxonomic classifications. Our analysis revealed that OTUs delimited by these methods corresponded to 71.39% of the evaluated species, with a notably higher congruence in Ensifera (88.53%) compared to Caelifera (52.15%). Across the dataset, we identified 54 lineages comprising cryptic species, indicating significant unrecognized diversity within these groups. Additionally, 21 instances of species being merged into consensus OTUs were observed, suggesting either the need for taxonomic revision or highlighting the limitations of current genetic markers. Among the methods tested, ABGD, particularly with the Kimura two-parameter model, was the most consistent with traditional taxonomy, yielding the highest consensus rates. In contrast, the PTP method exhibited the lowest consensus, often leading to an oversplitting of lineages. These findings underscore the complexity of species delimitation in recently radiated taxa and emphasize the importance of using multiple methodologies to accurately capture biodiversity, especially in regions characterized by a high prevalence of cryptic species.

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DOI: 10.3897/asp.83.e136516

Authors: Onur Uluar, Dragan P. Chobanov, Battal Çıplak

Abstract: A taxonomical practice without integration of systematics remains incomplete or produces incorrect definitions. To address this, we linked the taxonomy of the Poecilimon zonatus group to its systematics by examining its phylogeny and phylogeography. We used both mitochondrial and nuclear genes representing all species except P. varicornis. The mitochondrial matrix was subjected to phylogenetic analyses and species delimitation tests while phylogenetic signals in the nuclear data were assessed via haplotype network. Species delimitation tests suggested 12–16 species and the genetically divergent lineages were examined for phenotypic disparity. The results led to the following conclusions. (i) after the nomenclatural changes made here, P. zonatus group consists of 13 species, two of which are polytypic; P. salmani Sevgili syn. nov. is synonymized with P. ciplaki; the subspecies P. ciplaki denizliensis Kaya and P. zonatus datca Sevgili, Sirin, Heller & Lemonnier-Darcemont are elevated to species level as P. denizliensis Kaya stat. nov. and P. datca Sevgili, Sirin, Heller & Lemonnier-Darcemont stat. nov., respectively; P. boncukdagensis sp. nov., P. parazonatus sp. nov. and P. anisozonatus sp. nov., are described as new species, and P. datca montana subsp. nov. and P. denizliensis kizildagi subsp. nov. as new subspecies, (ii) the common ancestor of species corresponds to Mid Pleistocene Transition, suggesting the major climatic turnovers as the main evolutionary driver, (iii) the isolated relict ancestors on highlands evolved under similar selection pressures leading to a conserved phenotype, consequently, to limited morphological divergence despite their genetic differences; (iv) although morphological diagnosability is poor, each species meets the criteria of several species concepts.

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DOI: 10.3897/asp.82.e116541

Authors: Zoltán Kenyeres, Norbert Bauer, Maciej Kociński, Beata Grzywacz

Abstract: Steppes form large zonal habitats in Asia but only consist of localised outposts in Europe. An ideal subject for the study of differences within species between the main steppe zone and the localized more western outposts is the Orthopteran Stenobothrus eurasius, widespread across the Siberian and Central Asian steppes but present only in isolated relic populations at the western edge of its area. We used genetic and morphological analyses to detect possible differences among these relic populations. We carried out a study on morphological parameters of wings in parallel with the comparison of four DNA fragments (cytochrome c oxidase subunit I, 12S rRNA and the mtDNA control region, cytochrome B, nuclear internal transcribed spacers plus the 5.8S rRNA region) involving 15 extrazonal populations of the species. St. nigromaculatus was used as an outgroup taxon in the genetic analyses. Variability of the morphological characters of St. eurasius individuals was higher within the regions than amongst the regions. The two Stenobothrus species were not separated based on the CR gene. Samples of both Stenobothrus species were separated on the COI, cytB and ITS1-5.8S-ITS2 phylogenetic trees with high support (PP = 1) in Bayesian analyses but clear genetic lineages were not revealed, and populations of the focal species were not grouped according to their geographic locations. The similarity of this species in different steppe outposts supports the hypothesis that St. eurasius was widespread in the more extensive steppe areas that were once present, but the extension of agricultural landuse reduced the steppe habitats resulting in the current patchy distribution of St. eurasius limited to the remaining habitats.

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DOI: 10.3897/asp.80.e82447

Authors: Maciej Kociński, Dragan Chobanov, Beata Grzywacz

Abstract: The Balkan Peninsula is treated as a hotspot of biodiversity with over 40% of European bush-crickets occurring there. Poecilimon Fischer, 1853 is one of the largest Palaearctic orthopteran genera containing several species groups. One of them is the Poecilimon ornatus group (Schmidt, 1850) with 13 species and 5 subspecies. Among the group, the Poecilimon affinis complex is designated as consisting of P. pseudornatus Ingrisch & Pavićević, 2010, P. nonveilleri Ingrisch & Pavićević, 2010, and five subspecies of P. affinis (Frivaldszky, 1868). The aim of this study is to reconstruct the phylogenetic relationships among taxa of the P. ornatus group and to elucidate the position of taxa related to the P. affinis complex. Molecular phylogeny supported the monophyly of the P. ornatus group and showed that their ancestor probably originated in the southern Balkans. The underlying processes are thought to be six dispersals and five vicariance events linked to geological events and climate changes in the Pleistocene. The species delimitation analysis showed mostly nine hypothetical species among the group.

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DOI: 10.3897/asp.79.e66319

Authors: Simeon Borislavov Borissov, Georgi Hristov Hristov, Dragan Petrov Chobanov

Abstract: Abstract Parthenogenetic lineages are known to rapidly colonize large areas that become available after glacial periods as parthenogenetic reproduction is beneficial over mating when the favorable season is very short. The only obligatory parthenogenetic species of the largest bush-cricket subfamily Phaneropterinae is Poecilimon intermedius. It belongs to the Anatolio-Balkan lineage Poecilimon ampliatus species group and in contrast has a remarkably broad distribution from Central Europe to China, following the pattern of geographical parthenogenesis. In this study we provide a systematic revision of the P. ampliatus group based on mitochondrial (ND2) and nuclear (ITS) phylogeny. We estimate divergence times by applying secondary calibration on the ND2 tree to test for congruence between recent splits in the group and the Pleistocene climatic oscillations. We use ecological niche modelling to analyze the ecological requirements of the parthenogenetic P. intermedius and its sexually reproducing sister species P. ampliatus. By projecting on the conditions during the Last Glacial Maximum we outline the suitable areas for both species during the glacial cycles and discuss range shifts in response to climate change. Based on all results we hypothesize that the drought-tolerant P. intermedius originated during the recent glaciations in the southwestern part of its current range and rapidly radiated in a northeastern direction. Its sister species P. ampliatus, which is adapted to higher levels of precipitation, remained in the western Balkans, where populations retreated to higher altitudes during warming.

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