The invasive lilac leafhopper, Igutettix oculatus (Lindberg, 1929), continues to spread in Europe: new host plant and new findings: (Hemiptera: Cicadellidae, Typhlocybinae)

Die invasive Fliederblattzikade Igutettix oculatus (Lindberg, 1929) breitet sich weiter in Europa aus: Neue Wirtspflanze und neue Befunde. – Die ersten Funde der aus Ostasien stammenden Fliederblattzikade, Igutettix oculatus (Lindberg,1929), in Lettland und Litauen werden vorgestellt. Die Art wurde in den Regionen Kurzeme, Vidzeme und Zemgale (Lettland) und im Nordosten von Litauen nachgewiesen und lebt dort auf Wirtspflanzen der Gattungen Syringa (Flieder), Fraxinus (Esche) und Ligustrum (Liguster), alle der Familie Oleaceae zugehörig. Die gravierendsten Schäden wurden auf manchen Flieder-Arten und Liguster beobachtet. Schäden auf Esche wurden besonders auf jungen Bäumen an schattigen Standorten festgestellt. Derzeit ist die Fliederblattzikade aus 6 europäischen Ländern bekannt – Weißrussland, Estland, Finnland, Lettland, Litauen und Russland. In warmen und trockenen Sommern kann sie zu einem ernsthaften Pflanzenschädling werden. Liguster wurde als neue Wirtspflanze nachgewiesen. Da auf Esche auch in naturnahen Lebensräumen hohe Dichten und beachtliche Schäden auftreten können, kann die Art als invasiv im engeren Sinne bezeichnet werden.This paper reports the first records of the alien lilac leafhopper, Igutettix oculatus (Lindberg, 1929), in Latvia and Lithuania. The species was found on plants belonging to three genera – Fraxinus, Ligustrum and Syringa (all members of the family Oleaceae) in Kurzeme, Vidzeme and Zemgale regions of Latvia and in north-eastern parts of Lithuania. The most serious damage was observed on some lilacs (Syringa spp.) and on Ligustrum vulgare. Injuries on Fraxinus excelsior were observed mainly on young trees, especially in shaded habitats. To date, this East Asian leafhopper is known from six European countries – Belarus, Estonia, Finland, Latvia, Lithuania and the Russian Federation (European part) and can be a serious plant pest during warm and dry summers. Ligustrum vulgare is recorded as a new host plant. As lilac leafhopper produces highly dense populations on Fraxinus excelsior and causes notable injuries on young trees, it can be treated as an invasive species in Europe

Cepaea vindobonensis (C. Pfeiff er, 1828) in Latvia

Abstract Cepaea vindobonensis (C. Pfeiff er, 1828) is reported from one site from Riga city (Latvia). Th is is its only known population in Latvia. We briefl y discuss information about this record and we provide historical review of the oldest collection data on this species for Latvia

EVALUATION OF LATVIAN FLAX VARIETIES BY SEED YIELD AND QUALITY

Flax cultures give dual-purpose production – flax fibre and seeds. Flax varieties adapted to local climate conditions have breeded but up to now the profound research of its quality was not carried out. In our investigation we analysed flax varieties of Latvia selection for seed yield and quality in comparison with standard varieties ‘Vega 2’ and ‘Lirina’. In Latgale Agricultural Scientific Centre 10 Latvian flax varieties are cultivated and seed yield, 1000-seed weight, seed oil content (extracted by hot pressing method) and fatty acid content in flax seed oil (detected with gas chromatography method) have evaluated. Seed yields of fibre flax Latvian varieties are significantly higher in comparison with standard variety ‘Vega’. All analysed seed samples have high oil content (27- 47%) and there is high percentage of polyunsaturated fatty acids in oil (linoleic acid 10,6-16,9%, linolenic acid 54,7-62,1%). There is little difference in 1000-seed weight, content of oil in seeds, percentage of linoleic, linolenic, oleic, palmitic and stearic acid in oil between fibre flax and oil seed flax varieties. The difference between the varieties is more influential. Flaxes seeds from Latvian varieties are in high quality and can be used for food, medical and technical purposes

Citizen Science Reveals Unexpected Continental-Scale Evolutionary Change in a Model Organism

Organisms provide some of the most sensitive indicators of climate change and evolutionary responses are becoming apparent in species with short generation times. Large datasets on genetic polymorphism that can provide an historical benchmark against which to test for recent evolutionary responses are very rare, but an exception is found in the brown-lipped banded snail (Cepaea nemoralis). This species is sensitive to its thermal environment and exhibits several polymorphisms of shell colour and banding pattern affecting shell albedo in the majority of populations within its native range in Europe. We tested for evolutionary changes in shell albedo that might have been driven by the warming of the climate in Europe over the last half century by compiling an historical dataset for 6,515 native populations of C. nemoralis and comparing this with new data on nearly 3,000 populations. The new data were sampled mainly in 2009 through the Evolution MegaLab, a citizen science project that engaged thousands of volunteers in 15 countries throughout Europe in the biggest such exercise ever undertaken. A known geographic cline in the frequency of the colour phenotype with the highest albedo (yellow) was shown to have persisted and a difference in colour frequency between woodland and more open habitats was confirmed, but there was no general increase in the frequency of yellow shells. This may have been because snails adapted to a warming climate through behavioural thermoregulation. By contrast, we detected an unexpected decrease in the frequency of Unbanded shells and an increase in the Mid-banded morph. Neither of these evolutionary changes appears to be a direct response to climate change, indicating that the influence of other selective agents, possibly related to changing predation pressure and habitat change with effects on micro-climate

Eriophyoid mites (Acari: Prostigmata: Eriophyoidea) of Latvia: an annotated checklist

Stalažs, Arturs, Turka, Ināra (2019): Eriophyoid mites (Acari: Prostigmata: Eriophyoidea) of Latvia: an annotated checklist. Zootaxa 4629 (2): 211-236, DOI: https://doi.org/10.11646/zootaxa.4629.2.

Snail fauna of the oldest cemeteries from Riga (Latvia)

We report on the snail fauna from one of the oldest cemeteries from Riga city (Latvia), viz. Lielie kapi and Pokrova kapi. A list of all the snail species recorded from both cemeteries and limited information on the biotope conditions are given. Cecilioides acicula (O.F. Müller, 1774) is first recorded from Latvia and was found at a grassland within the tomb area of the Pokrova kapi cemetery

Summary of the results of General Additive Modeling of shell polymorphism in <i>Cepaea nemoralis</i> in the combined dataset of historical and 2009 samples collected throughout Europe.

<p>Statistics shown are coefficients (α) and t-values for unsmoothed terms and F-values for smoothed terms. P-values are approximate. n = sample size (number of populations), Dev% is the percent deviance accounted for by the model. Mid-banded frequency is calculated as a percentage of banded. Coefficient values are not given for the terms entered as smooth functions, because such function cannot be described by a single coefficient.</p>†<p>In this case the model omitting Habitat as an independent variable fits slightly better in terms of deviance than the model including Habitat, so no test statistic or p value can be calculated.</p