Steppe Species Research Articles

Monitoring of avifaune rare representatives of the akhtarsk salt lakes

Actively involving soil resources in economic activity, humanity didn’t notice how vast steppe expanses turned into fragmentary refugium for steppe species. So, regional flora and fauna are now preserved in inconveniences. One of such refugium of the Krasnodar Territory is the Akhtarsk salt lakes being the main ornithological places of the region. Monitoring studies of the ornithological composition of the biocenoses of the Akhtarsk salt lakes were conducted in 2018–2021. The composition and number of bird species of the Akhtarsk salt lakes have been revealed in the present article.

Monitoring of vegetation in the coastal zone of Lake Vshivoe

The article presents the results of the current state of flora of the coastal zone of Vshivoe Lake. This is a natural drainless water body at the watershed of the Grachevka and Egorlyk rivers. The composition and structure of plant biodiversity were identified and GPS coordinates for rare and endangered plant species were established. In the course of expeditionary studies of the coastal zone 30 m wide, we observed the disappearance of the water mirror and the increase of steppe vegetation species, the appearance of trees, shrubs. Throughout the entire coastline in the association Phragmites australis + Typha latifolia with a dense projective coverage of 81 to 98% grows 125 species of higher vascular plants belonging to 37 families and 95 genera. The species composition of coastal-water vegetation in 2022, compared to 2014, has decreased by one species, the species composition has changed in favour of weeds, there is afforestation of the territory at the expense of shrubs, they become more to 3-5 pcs per 100 m². Anthropogenic and climatic factors led to an increase in the number of steppe species from 24 to 32 and ruderal species from 17 to 32 species in 2022 compared to 2014. Four species of sedges, Carex riparia, C. melanostachya, C. hordeistichos, C. vulpina, were found and determined from 8 previously discovered rare species of the Red Books of the Russian Federation and Stavropol Krai, were found and determined: Tulipa biebershteiniana, Bellevalia sarmatica, Iris halophila, Iris taurica, Paeonia tenuifolia, Adonis vernalis, Dactylorhiza incarnata, Anemone sylvestris, which is 6.78 % of the floristic composition of the area. It was established that the majority of rare and endangered species populations in natural habitats are growing with a predominance of vegetative and juvenile individuals.

Carabus (Tomocarabus) bessarabicus Fischer von Waldheim, 1823 (Coleoptera: Carabidae)—New Steppe Element for the Bulgarian Fauna from the Karst Refugium of the Chepan Planina Mt.

During a study of the distribution and status of Carabus hungaricus Fabricius, 1792 (Coleoptera: Carabidae), with pitfall traps exposed between November 2021 and April 2022, immediately south of Petrovski Krast Peak (1206 m a.s.l.) in the Chepan Planina Mt., at 1188 m a.s.l., the rare and stenotopic steppe species Carabus bessarabicus Fischer von Waldheim, 1823, was found for the first time in Bulgaria and the European Union. In October 2022, elytra of both species were also found by handpicking in the same area. The coexistence of these two specific and rare steppe species has been recorded only in few localities in Ukraine and Russia and in no EU country. This finding is also very interesting given the high conservation status of Carabus bessarabicus, the significant remoteness of its newly established locality (more than 1200 km) from its previously known range, and its strong south-westward drift. The species is used as a bioindicator for the anthropogenically uninfluenced steppe environment, which can also probably be applied in Bulgaria. The establishment of this first record for the EU also implies an increase in the conservation status of the species through its inclusion in the Union-wide conservation documents and ecological networks.

МЛЕКОПИТАЮЩИЕ ПОЗДНЕГО НЕОПЛЕЙСТОЦЕНА ПРЕДАЛТАЙСКОЙ РАВНИНЫ ПО МАТЕРИАЛАМ РАЗРЕЗА НОВОСУРТАЕВКА

The paper deals with a performed study of geological structure and gathering of mammals remains in the Novosurtaevka section. New data showed the presence of two locations of fossil mammals in this section. One location is associated with a channel sand deposited in the Middle Kargian time (MIS 3) about 40550±650 y.a. By the end of the Kargian time (MIS 3) about 30300±350 y.a., the river began to meander, resulting in the replacement of the channel sedimentation by flood-plain one. During this period, the location of Novosurtaevka 2 was formed. The fauna of the Novosurtaevka 1 location is typical for the Middle and Late Pleistocene of the Pre-Altai Plain. The fauna is characterized by the co-existence of species of steppe and forest-steppe biotopes. The presence of remains of red-backed mices in the location is most likely determined by development of floodplain forests in steppe zone and proximity to the mountainous region. Data on malacofauna and vegetation confirm the development of spruce forests and floodplain vegetation in the surrounding areas.

Origin of the central European steppe flora: insights from palaeodistribution modelling and migration simulations

The biogeographic origin of the species‐rich steppe grasslands in central Europe has long been debated. The alternative hypotheses are long‐term species persistence in situ versus immigration from the south‐east, either after the last glacial maximum (LGM) or after the Neolithic landscape deforestation. We ask whether macroclimate‐based models of habitat suitability support either of these hypotheses and search for macroclimatically suitable ‘source areas' from which species could colonise the areas occupied in Europe today. We modelled habitat suitability for 104 species of the central European steppes and projected these models to 10 periods between the LGM and the present using downscaled CCSM3 simulations. By simulating postglacial migration, we identified potential source areas for each species in the LGM and mid‐Holocene and examined whether their location differed among three ecological and five chorological species groups.The central European macroclimate during the cold phases of the Late Pleistocene was suitable for species now typical of Asian desert steppes, whereas the warmer Bølling–Allerød and Holocene macroclimates supported the occurrence of present‐day central European steppe flora. The models suggest that the LGM source areas of these species ranged from south‐eastern France through the Adriatic region and the Balkan Peninsula to the Black‐Sea region but extended to central Europe in the mid‐Holocene. Their locations differed considerably among ecological and chorological groups in both periods. Therefore, our models support the hypothesis that during the Pleistocene cold periods, the largest populations of these species occurred in southern and south‐eastern Europe and some of them may have later colonised central Europe. If some populations occurred in central Europe during the LGM, as suggested by recent genetic analyses, they were likely restricted to microrefugia embedded in the landscape matrix of species‐poor cold steppe. The precipitation‐rich mid‐Holocene climate had no direct negative impact on the central European steppe flora.

Floristic diversity and vegetation of communities associated with two endemic Dianthus species in the montane steppes of northeastern Iran

The study aimed to analyze vegetation data using a phytosociological method and to identify species composition and relationships between vegetation and environmental data in communities that include two threatened species (Dianthus pseudocrinitus Behrooz. & Joharchi and D. polylepis Bien. ex Boiss.) endemic to the montane steppes of Khorassan‐Kopet Dagh floristic province in northeastern Iran. We sampled 75 vegetation plots in 15 sites where the endemic Dianthus species occur. In order to evaluate community characterization of the species, we investigated floristic composition, life‐form spectrum and the phytogeography of the study sites. In all, 370 plant species were recorded, belonging to 184 genera in 45 families. Floristic analysis revealed that Hemicryptophytes are the dominant life‐form in these habitats, and Iran‐Turanian floristic elements contributed 74.5% of the total number of species. Classification analysis based on TWINSPAN showed a clear separation of the study sites based on Dianthus taxa, which was confirmed by detrended correspondence analysis (DCA). The results reflected the highly diverse flora at all Dianthus sites. Species composition and the distribution of vegetation groups were influenced by some environmental factors. Habitats for both species could be managed by a community ecological approach; our study provided a better knowledge of these communities' ecological and floristic composition to enhance effective management and conservation of the threatened species.

Trends in soil microclimate and modeled impacts on germination timing in the sagebrush steppe

AbstractPast and projected changes in climate affect soil microclimate, impacting seeds that use soil moisture and soil temperature as cues for germination. Seed germination and plant establishment are among the most important processes regulating plant community assembly in response to climate change. Changes in germination timing expose seedlings to new abiotic and biotic risk factors that can affect recruitment success. Species with seed dormancy strategies to avoid harsh winter conditions could experience more mortality if changes in germination timing cause early germination and subsequent exposure to freezing conditions. We analyzed soil microclimate trends in the sagebrush steppe from 1979 to 2017 using a soil physics model (SHAW) and calculated the germination timing of native species used in restoration efforts with wet‐thermal response curves from lab trials. We applied the germination curves to modeled soil microclimate at 10 sites in the sagebrush steppe. Our results indicate that warmer and wetter fall seasons have become more prevalent and will likely lead to accelerated germination of several native restoration species in the sagebrush steppe. Changes to spring soil conditions favor slightly more germination in early spring, but strong trends of earlier onset of spring soil conditions were not evident. Trends in climate have created drier and warmer summer seedbed conditions, likely to increase stress on seedlings. Historic cycles of alternating slow or fast germination appeared less frequently during the last 12 years of the study (2004–2016). Seedbed microclimate trends will likely impact seedling establishment by altering germination timing and exposing seeds to more harsh abiotic conditions, likely resulting in decreased recruitment of native species and increased abundance of invasive annual grasses.

Effects of deficit irrigation on seed production performance and water use efficiency of two native plant species in arid areas

Scientific irrigation is of great significance to plant seed production. With two excellent native plant species in desert steppe, Agropyron mongolicum and Lespedeza potaninii, as the objects, and full irrigation as the control, we explored the effects of deficit irrigation in different growth stages on the seed production and water use efficiency (WUE) of those two species. The results showed that, compared with the control, soil water content of both species decreased under deficit irrigation. The decrease of soil water content of A. mongolicum mainly occurred in the 0-60 cm soil layer, while there was no obvious stratification for the reduction of soil water content of L. potaninii. There were significant differences in the yield components of A. mongolica under deficit irrigation. The seed yield of deficit irrigation at the flowering stage was the highest. There were significant differences in the numbers of fertile tillers, florets and pods of L. potaninii among treatments, but no significant difference in seed yield. There were positive correlations between seed yield of A. mongolicum and the numbers of fertile tillers (r=0.776) and spikelets (r=0.717). The racemes of L. potaninii was significantly negatively correlated with the number of fertile tillers (r=-0.685), and positively correlated with the number of florets (r=0.412). Compared with full irrigation, water consumption of seed production of the two native plant species was reduced under deficit irrigation, but water use efficiency was improved, with the strongest improvement at the flowering stage of A. mongolicum (32.9%) and at the branching stage of L. potaninii (27.4%). Therefore, proper deficit irrigation could improve water use efficiency of both plant species. From the perspective of water use efficiency and seed yield, deficit irrigation could be used for artificial breeding of A. mongolicum and L. potaninii seeds in arid area, with the suitable growth stage for deficit being the flowering and the branching stages, respectively.

Evaluation of the Toxicity of Chemical and Biogenic Insecticides to Three Outbreaking Insects in Desert Steppes of Northern China.

The locusts Oedales asiaticus (Bey-Bienko) and Myrmeleotettix palpalis (Zubovski) (Orthoptera Acrididae) and the leaf beetle Galeruca daurica (Joannis) (Coleoptera, Chrysomelidae) are economically devastating insect species in the desert steppes of Northern China. Control is mainly and frequently dependent on highly toxic chemicals. To date, there have been no complete and comprehensive reports of insecticide applications to these key pests. In this study, laboratory bioassays were carried out to determine and compare the toxicity of twelve insecticides to three outbreaking insects, O. asiaticus, M. palpalis, and G. daurica, from three typical desert steppe regions, SZWQ, XHQ and WLTQQ, respectively. The responses of the two locust species and the leaf beetle were evaluated by topical application and leaf dip bioassay techniques across a range of concentrations to develop dosage–mortality regressions. The insecticides tested included six chemical insecticides (β-cypermethrin, imidacloprid, phoxim, λ-cyhalothrin, methomyl, chlorantraniliprole) and six biogenic insecticides (spinosad, avermectin, rotenone, matrine, azadiracthin, and methoxyfenozide). The results showed that phoxim, λ-cyhalothrin, β-cypermethrin and spinosad showed highly toxic activity to O.asiaticus, M. palpalis, and G. daurica, while methonyl, chlorantraniliprole, and rotenone were moderately toxic to both locust species and the leaf beetle. The LC50 values of matrine, azadiractin, and avermectin were more than 1 μg a.i./adult for O. asiaticus and M. palpalis, the LC50 values of which were higher 2 g/L for G. daurica. Our findings complement information from previous similar studies and will inform future studies relating to the control of outbreaking insects, such as O.asiaticus, M. palpalis, and G. daurica in desert steppes of northern China. This study is also expected to provide basic data on the use of chemical and biogenic insecticides for application in desert steppes.

Combining phylogeography and landscape genetics reveals genetic variation and distribution patterns of Stipa breviflora populations

• Stipa. breviflora originated on the northeastern QTP and the eastern Helan mountains. • S. breviflora originated in the late Miocene. • The genetic differentiation of S. breviflora was mainly caused by IBD. Historical and contemporary microevolutionary processes influence the extent and structure of genetic variation. Combining phylogeography and landscape genetics is an important approach for delineating the formation mechanisms about the patterns of genetic structures. Grassland ecosystems comprise approximately one-third of Earth's vegetative cover. The spatial distribution of genetic variations derived from dominant plant species in steppes is helpful to understand the origin and evolution of this kind of vegetation. In this paper, we took Stipa breviflora , a dominant species of desert steppe, as an example, and conducted the research on both chloroplast DNA sequences and microsatellite loci of populations. The results of analyzing haplotype and microsatellite diversity revealed that S. breviflora most probably originated from the region in eastern Helan Mountains and northeast of Qinghai-Tibet Plateau (QTP) during the late Miocene. The genetic variation distribution of the species was in accordance with the core-periphery hypothesis (CPH), i.e., populations located at the periphery of a species’ range should have lower levels of genetic variation than those at the center of the range. Paleoclimatic fluctuations contributed to haplotype evolution, while geographical distance played an important role in driving contemporary genetic differentiation. Our findings highlight the complexity of intraspecific evolution and clarify the biogeographical history of desert steppes based on molecular signals.

Prediction of plant diversity under different stocking rates based on functional traits of constructive species in a desert steppe, northern China

Excessive grazing causes a decrease in plant diversity of grassland and also leads to changes in the functional traits of grassland plants. Based on the relationship between plant diversity and the functional traits of constructive species, the patterns of change in plant diversity can be predicted based on change in plant functional traits under different stocking rates. For the present study, Stipa breviflora desert steppe in Inner Mongolia was studied to characterize the plant community and population characteristics and plant functional traits of S. breviflora in grazing areas with different stocking rates [without grazing, light grazing (LG, 0.93 sheep unit hm–2half yr–1), moderate grazing (MG, 1.82 sheep unit hm–2half yr–1), heavy grazing (HG, 2.71 sheep unit hm–2 half yr–1)]. The results showed that: (1) LG significantly weakened the competitive advantage of the constructive species (S. breviflora) (P < 0.05), while HG significantly strengthened its competitive advantage in the community (P < 0.05); (2) Changes in plant diversity were generally significantly related to changes in S. breviflora root traits. The competitive advantage of S. breviflora in the community and the change in root traits could be used to predict the change in plant diversity in the desert steppe under different stocking rates. This research can provide a theoretical basis for maintaining plant diversity and sustainability in the desert steppe.

Rhizosphere soil microbial community and its response to different utilization patterns in the semi-arid alpine grassland of northern Tibet

As the link between plants and soils, rhizosphere soil microorganisms play an important role in the element cycle. This study aimed to understand the response of the rhizosphere soil microbial community structure and interaction network to grassland utilization in the alpine steppe of the northern Tibet Plateau. High-throughput sequencing was employed to study the composition, diversity, and species interaction network of rhizosphere soil microbial communities under grazing, mowing, and enclosing treatments. Proteobacteria (47.19%) and Actinobacteria (42.20%) were the dominant bacteria in the rhizosphere soil. There was no significant difference in relative abundance among rhizosphere soil microorganisms at phylum and genus levels, but differences were found in Chlorobi, Ignavibacteriae, and Micromonospora. The alpha diversity index based on Shannon, Chao1, and Simpson indices revealed that except for a significant difference in the Shannon index of the Artemisia nanschanica group, the richness and evenness of rhizosphere soil microbial communities among all groups were similar. Non-metric multidimensional scaling (NMDS) and multi-response permutation procedure (MRPP) analyses showed that the inter-group differences of three plants (Stipa purpurea, Carex moorcroftii, and Artemisia nanschanica) were greater than the differences within the groups; however, only the inter-group difference with the Stipa purpurea group was significant. The microbial interaction network showed that the network complexity of the Artemisia nanschanica group and the enclosing treatment, which were not easily influenced by external factors, were higher than those of the other groups and treatments; this again demonstrated that Proteobacteria and Actinobacteria were the network core microbial species in alpine steppe of the northern Tibet Plateau and were crucial for maintaining stability of the microbial communities. Findings from this study provide a theoretical basis for the restoration of degraded alpine grassland and the development of microbial functions.

Examination of Forest Steppe Species in the Case of Areas Where Traditional Cultivation Was Abandoned

The thousands of kilometers of forest steppes in Eurasia belong to the most threatened ecosystems thanks to habitat loss. We have limited knowledge on the recolonization ability of forest steppe species to date, which is the reason we examined the textural and structural changes in these species during secondary succession in areas of different former land use. The species number, cover, and diversity of forest steppe species, especially those of the Festuco-Brometea group, became significant for all three types in the oldest fallows. The number and proportion of forest steppe species have been steadily increasing in abandoned vineyards and arable land, indicating that forest steppe species are able to rapidly recolonize. The increase in the number and cover of forest steppe species in abandoned grasslands reveals that the replacement of the species pool of these grasslands is not necessarily accompanied by degradation, but also by the appearance and spread of valuable natural species if the habitat is sufficiently patchy. The proportions of habitat categories level off in abandoned vineyards and arable land as abandonment progresses. The cover rates of disturbed habitats species were negligible for all three types for the third decade after abandonment, indicating a change in the quality of the species pool.

Precipitation variations, rather than N deposition, determine plant ecophysiological traits in a desert steppe in Northern China

Understanding how plant ecophysiological traits of coexisting species within a community respond to environmental changes could help to predict the shift in plant community structure and function, but it remains limited in the scenarios of co-occurring precipitation variations and N deposition. A two-year field experiment was conducted to explore the effects of large precipitation changes (reduced and increased precipitation amount by 25% and 50% relative to ambient control) and high N deposition (10 g N m−2 yr−1) on a series of leaf ecophysiological traits of three dominant species (Stipa tianschanica, a C3 grass; Cleistogenes squarrosa, a C4 grass; and Artemisia capillaris, a C3 forb) in a desert steppe in Northern China. Increasing precipitation significantly linearly promoted the leaf light-saturated photosynthesis rate (Asat) and N use efficiency of the two C3 species, irrespective of N addition. The rises in Asat of both C3 species were mainly caused by increased soil moisture, which strongly induced increases in leaf stomatal conductance (gs) and declines in quantum yield of photosystem II (ΦPSII). However, the Asat of the two C3 species was weakly correlated with their specific leaf area and leaf N concentration, whereas the Asat of the C4 grass was negatively related to its leaf N. Moreover, the Asat, height, and aboveground biomass of the forbs were much more water-sensitive than those of both grass species, with a consequence of the most dominant species turning from grass to forbs as precipitation increased. Our findings highlight that water limitation, rather than N deficit, is the largest factor controlling plant growth in drylands, and plant species-specific ecophysiological responses to precipitation fluctuations will cause a substantial shift in the production and composition of plant community.

Numbers matter: Predatory ability increases with forager group size in omnivorous ant species with similar predatory traits

Abstract Predation is an important force structuring ecological communities. However, it is still controversial whether larger predator groups are more efficient at exploiting abundant resources. Here, we explored the association between the number of foragers and predation ability in generalist ant species that differ in forager numbers when exploiting resources. We conducted a field experiment by increasing caterpillar density around nests of two abundant Dorymyrmex ant species in the semiarid Patagonian steppe, where D. tener allocates a higher number of foragers to resource exploitation than D. antarcticus. We (1) compared the association between predation effectiveness (success to complete a task) and efficiency (speed of task performance and economy of foragers) with the number of foragers involved between species, and (2) studied how they responded numerically to increasing prey densities, by sequentially adding 3, 6 and 12 larvae in the same foraging arena. Finally, (3) we compared behavioural and morphological traits related to predation between these ant species. Although D. tener discovered a similar number of arenas with larvae than D. antarcticus, it was more effective as it recruited more and removed more larvae. This species was also more efficient than D. antarcticus in all predation subtasks, and the time used to remove one larva depended on prey density, being faster for the high‐larvae density. Besides the number of foragers, ant species did not differ in other behavioural traits, and D. tener's foragers were slightly larger than those of D. antarcticus. This study illustrates how, in social predators, the predator group size and individual behavioural characteristics may act in conjunction, with relevant consequences at ecological, evolutionary, and applied levels, including potential implications for pest control.

Ecosystem engineering influence of Mongolian marmots (Marmota sibirica) on small mammal communities in Mongolia

Mongolian marmots (Marmota sibirica) live in colonies that consist of numerous burrows and are considered ecosystem engineers. Although once a common steppe species, marmots are now endangered due to overharvesting, which has led to concerns over the impacts of their loss on other species. The decline of marmots likely affected other species given their importance to the ecosystems they inhabit. To examine the role of marmots on small mammal, we established Sherman traps and drift fence arrays with associated pitfall and funnel traps on active marmot colonies, inactive colonies, and control sites in the forest-steppe and semi-desert zones of Mongolia. Overall, we identified 385 individuals representing 11 species of rodents and 1 species of bat in Ikh Nart and 149 individuals representing 2 species of rodents and 1 species of insectivore from Hustai. We found mixed results between diversity indices and abundance of small mammals on treatment and control sites, complicating the picture. During periods of greater precipitation and resulting higher vegetation cover, species abundance and the Shannon-Wiener, Simpson's, and evenness indices all changed significantly, suggesting that the effect of marmots on other species varies based on environmental conditions.

Allium pallasii and A. caricifolium-Surprisingly Diverse Old Steppe Species, Showing a Clear Geographical Barrier in the Area of Lake Zaysan.

Polymorph Allium pallasii s.l. from monotypic A. sect. Pallasia was studied using a wide spectrum of methods and divided into two clearly morphologically, geographically, cytologically and genetically isolated species: A. pallasii s. str.—North-East Kazakhstan, Western Siberia, and the Altai Mountains; A. caricifolium—Kyrgyzstan, Northwest China, South-East Kazakhstan until Zaysan Lake in the east. Despite serious genetic differences, both species are sisters and are related to species of the A. sect. Codonoprasum (Subg. Allium). Allium caricifolium differs from A. pallasii s. str. by taller stems, dense inflorescence, and with filaments longer than perianth. The possible phylogenetic reasons for the separation of these species are discussed. A nomenclature analysis of synonyms was carried out.

The Effect of Soil Water Deficiency on Water Use Strategies and Response Mechanisms of Glycyrrhiza uralensis Fisch.

We aimed to investigate the water use strategies and the responses to water shortages in Glycyrrhiza uralensis, which is a dominant species in the desert steppe. Water stress gradients included control, mild, moderate, and severe. The time intervals were 15, 30, 45, and 60 d. Our study suggested that with the aggravation of water stress intensity, the total biomass of Glycyrrhiza uralensis gradually decreased and allometric growth was preferred to underground biomass accumulation. From 30 d and mild to moderate water stress, the water potential (WP) of leaves decreased considerably compared to the CK. The relative water content (EWC) decreased over time and had a narrow range of variation. Proline (PR) was continuously increased, then declined at 45–60 d under severe and more severe water stress. The δ13C values increased in all organs, showed roots > stems > leaves. The net photosynthetic rate (Pn) and transpiration rate (Tr) decreased to varying degrees. The instantaneous water use efficiency (WUEi) and limiting value of stomata (Ls) increased continuously at first and decreased under severe water stress. Meanwhile, severe water stress triggered the most significant changes in chloroplast and guard cell morphology. In summary, Glycyrrhiza uralensis could maintain water content and turgor pressure under water stress, promote root biomass accumulation, and improve water use efficiency, a water-conservation strategy indicating a mechanism both avoidable dehydration and tolerable drought.

A new Nalassus Mulsant, 1854 (Coleoptera: Tenebrionidae) from Transcaucasia with a key to species from the Greater Caucasus and notes on the taxonomy, distribution, bionomics and trophic relations

A brief well-illustrated review of the tenebrionid genus Nalassus Mulsant, 1854 from the Greater Caucasus is presented. A new species, N. (Caucasonotus) negrobovi Nabozhenko, sp. n. is described from the alpine zone of Abkhazia. This species is similar to N. dombaicus (Nabozhenko, 2000), N. adriani (Reitter, 1922) and N. alanicus (Nabozhenko, 2000), but differs in the structure of eyes, antennae, pronotum and elytral interstriae. The following new synonyms are proposed after examination of a series of beetles and type specimens: Nalas­sus dissonus Nabozhenko, 2001 = Nalassus lutshniki Nabozhenko, 2001, syn. n.; Nalassus colchicus madlenae Nabozhenko, 2013 = Nalassus kartvelius Nabozhenko, 2013, syn. n.; Helops cambyses Seidlitz, 1895 = Cylindronotus ahngeri Medvedev, 1998, syn. n. Keys to species from the Greater Caucasus on males and females are given. New data on bionomics, landscape and habitat distribution and trophic relations are given. Interesting patterns are observed at the level of ecological groups: forest species feed mainly on corticolous foliose lichens from the family Physciaceae Zahlbr., while alpine Nalassus use saxicolous foliose lichens from the family Parmeliaceae Zenker; steppe species feed on terricolous foliose lichens at least from the family Cladoniaceae Zenker.

Exploring Cold Hardiness within a Butterfly Clade: Supercooling Ability and Polyol Profiles in European Satyrinae.

Simple SummaryIn insects distributed in temperate and cold zones, cold hardiness during overwintering crucially affects the distribution, including range shifts due to climate change. Our previous work on the genus Erebia, a cold-adapted and species-rich group of the sub-family Satyrinae (Nymphalidae), disclosed unexpected diversity of cold hardiness strategies, with closely related species surviving or not surviving freezing of larval body fluids. Asking whether this diversity is peculiar to this genus, or may be common in the Satyrinae clade, we investigated supercooling ability, contents of sugars and polyols in overwintering larvae tissues, and evolutionary signal of these traits of eight European Satyrinae species (from seven genera) and compared them with the Erebia representatives investigated earlier. We show that cold hardiness strategies are indeed diverse in the group and that high mountain and continental steppe species employ similar cryoprotection mechanisms, differing from those employed by species of more mesic environments. The cold hardiness of overwintering stages affects the distribution of temperate and cold-zone insects. Studies on Erebia, a species-rich cold-zone butterfly genus, detected unexpected diversity of cold hardiness traits. We expanded our investigation to eight Satyrinae species of seven genera. We assessed Autumn and Winter supercooling points (SCPs) and concentrations of putatively cryoprotective sugars and polyols via gas chromatography–mass spectrometry. Aphantopus hyperantus and Hipparchia semele survived freezing of body fluids; Coenonympha arcania, C. gardetta, and Melanargia galathea died prior to freezing; Maniola jurtina, Chazara briseis, and Minois dryas displayed a mixed response. SCP varied from −22 to −9 °C among species. Total sugar and polyol concentrations (TSPC) varied sixfold (2 to 12 μg × mg−1) and eightfold including the Erebia spp. results. SCP and TSPC did not correlate. Alpine Erebia spp. contained high trehalose, threitol, and erythritol; C. briseis and C. gardetta contained high ribitol and trehalose; lowland species contained high saccharose, maltose, fructose, and sorbitol. SCP, TSPC, and glycerol concentrations were affected by phylogeny. Species of mountains or steppes tend to be freeze-avoidant, overwinter as young larvae, and contain high concentrations of trehalose, while those of mesic environments tend to be freeze-tolerant, overwinter as later instars, and rely on compounds such as maltose, saccharose, and fructose.