Shell Color Research Articles

The Variability of Quality Traits of Table Eggs and Eggshell Mineral Composition Depending on Hens' Breed and Eggshell Color.

Simple SummaryThe quality of the bird’s eggshell is extremely important because it constitutes a barrier that protects the developing embryo from external conditions. The shell color is a characteristic for a specific breed and its intensity is one of the basic selection criteria, especially among ornamental breeds of hens. The presence or absence of a specific dye is genetically determined, and environmental conditions or nutrition affect it only to a negligible degree. The shell is an inorganic part of the egg. Differences in the mineral composition are determined mainly by the feeding system and the age of birds, although differences are also observed between the lines or breeds, so probably also due to the color. The content of given elements affects the shell quality, determining its strength, thickness, or preventing the appearance of defects that affect the hatching results. In case of table eggs the variability of colors is attractive for consumers, particularly if the differences are extreme (white, green, brown). Based on the study, it was clearly visible that genetically determined eggshell color affects not only the quality of shell itself but also the whole egg parameters.The aim of the study was to evaluate the relationship between the eggshell color parameters and its mineral composition as well as the internal quality of eggs derived from various breeds of hens, varied by eggshell color: seledine from Araucana, brown from Marans, and white from Leghorn. The sample consisted of 180 eggs (60/group) The eggshell color was measured using CIE L*a*b* system. The quality evaluation included traits of whole egg (weight, specific gravity, proportions of elements, shape index), yolk (weight, color, index, pH), albumen (weight, height, pH), and shell (color, strength, weight, thickness, density). The mineral composition of eggshells was analyzed. The eggs origin affected the quality characteristics of particular egg elements (p < 0.001). However, the impact of analyzed colors on the egg quality traits varied, and in the case of whole egg and albumen traits the most favorable was the white color (p ≤ 0.05), while in the case of the strength of shell or its thickness it was the dark brown color (p ≤ 0.05). The eggshell color influenced variations in its mineral composition (p < 0.001) except potassium and sodium content, while the proportion of particular mineral elements in shell was correlated with the L*a*b* color space coordinates (p ≤ 0.05).

Comparative Egg Production, Quality and Hatchability in Three Chicken Genotypes under Humid Tropical Conditions

Comparative study on egg production and hatchability characteristics in Nigerian local (NL; n=24), FUNAAB-α (F-α; n=24) and Transylvanian naked neck (TNN; n=24) chickens aged 25 weeks old was carried out for 4 weeks. Three hundred and sixty hatchable eggs each were used for quality characteristics determination and for incubation. F-α had significantly (P&lt;0.001) higher egg production (90.3%) than TNN (76.9%) while TNN was higher than NL (58.3%). Egg weight (EWT), length, width and surface area, albumen height, weight, percentage and index, shell weight, color and internal quality unit (IQU) were significantly (P&lt;0.001) affected by genotype. These followed the pattern: NL&lt;F-α&lt;TNN. F-α and TNN had significantly (P&lt;0.001) higher values than NL in egg shape index, yolk weight, height and diameter. Yolk colour index was significantly (P&lt;0.01) higher in TNN than in F-α. Yolk percentage and yolk-albumen ratio followed the pattern: NL&gt;F-α&gt;TNN. NL had (P&lt;0.001) thicker and higher shell percentage (SP) than F-α and TNN. Higher Haugh unit (HU) was recorded in TNN than in NL and F-α. Fertility was significantly (P&lt;0.05) higher in F-α than in TNN. Hatchability was not (P&gt;0.05) affected by genotype. Chick weight and chick: egg ratio were significantly (P&lt;0.001) by genotype. TNN had higher chick weight and yield than F-α and NL chicks. In conclusion, F-α laid more eggs than others, exhibited higher fertility with longer chicks at hatch. TNN is superior in EWT, HU, IQU and chick yield. NL had higher SP than others.&#x0D; Keywords: Egg production, Egg quality, FUNAAB alpha chicken, Hatchability, Transylvanian naked neck chicken.

A new species of cone snail, Conus laccadivensis sp. nov.: (Gastropoda: Conidae) from the Islands of Lakshadweep Archipelago

The present paper describes the cone snail, Conus laccadivensis sp. nov., based on the morphological and molecular characters of the materials collected from Kalpeni and Androth Islands of Lakshadweep Archipelago. The species closely resembles the tropical species Conus distans (Hwass in Bruguière (1792) which is widely distributed throughout the Indo-Pacific regions. Morphologically C laccadivensis sp. nov., differs from C. distans in shell colour and spire characteristics. Conus laccadivensis sp. nov., possess distinct colour patterns with large and closely spaced coronations. The maximum likelihood clustering approaches using the mitochondrial genes such as COI, 16S rRNA and 12S rRNA revealed a separate genetic cluster confirming the newly identified species.

Identification of shell-color-related microRNAs in the Manila clam Ruditapes philippinarum using high-throughput sequencing of small RNA transcriptomes

Shell-color polymorphism is a common phenomenon in several mollusk species and has been associated with thermal capacity, developmental stability, shell strength, and immunity. Shell-color polymorphism has been related to the differential expression of genes in several signal transduction pathways; however, the functions of micro-RNAs (miRNAs) in shell-color formation remain unclear. In the present study, we compared high-quality, small-RNA transcriptomes in three strains of the Manila clam Ruditapes philippinarum with specific shell-color patterns, artificially selected for six generations. Totals of 114 known and 208 novel miRNAs were identified by high-throughput sequencing, of which nine known and one novel miRNA were verified by stem-loop quantitative real time-polymerase chain reaction. Predicted miRNA targets were subjected to Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses. miR-137 and miR-216b and the Hedgehog signaling pathway and Wnt signaling pathway were identified as being potentially involved in pigment formation and regulation in R. philippinarum. These results may help to clarify the role of miRNAs in shell coloration and shed light on the mechanisms regulating color formation in bivalve shells.

Shell banding and colour polymorphism of introduced snailCepaea hortensis (Gastropoda, Pulmonata, Helicidae)from some parts of Eastern Europe

The phenotypic composition of C. hortensis colonies was studied in Western Ukraine (more than 30 thousand adults from 23 settlements and 5 administrative regions) and the Moscow region of Russia (more than 500 adults and juveniles from two colonies in Moscow and Vidnoe). Most Western Ukrainian colonies were characterized by the absence of pink shells, the high frequencies of unbanded shells (70% or more), as well as the white ground colour in all banded shells. It is supposed that the latter feature makes it possible to reliably identify the colonies formed by the descendants of the primary introduction of C. hortensis into Western Ukraine, which occurred in the 20th century, from later and independent repeated introductions of this species. Unlike Western Ukraine, snails with yellow banded and pink shells were found in both colonies from the Moscow region. Pink banded shells were registered only in Moscow as well as in two colonies from Lviv. In two of the three colonies mentioned, part of the pink unbanded (Moscow) or all pink shells (Lviv) had a dark lip.

Qualitative and quantitative methods show stability in patterns of Cepaea nemoralis shell polymorphism in the Pyrenees over five decades.

Over the past century, the study of animal color has been critical in establishing some of the founding principles of biology, especially in genetics and evolution. In this regard, one of the emerging strengths of working with the land snail genus Cepaea is that historical collections can be compared against modern‐day samples, for instance, to understand the impact of changing climate and habitat upon shell morph frequencies. However, one potential limitation is that prior studies scored shell ground color by eye into three discrete colours yellow, pink, or brown. This incurs both potential error and bias in comparative surveys. In this study, we therefore aimed to use a quantitative method to score shell color and evaluated it by comparing patterns of C. nemoralis shell color polymorphism in the Pyrenees, using both methods on present‐day samples, and against historical data gathered in the 1960s using the traditional method. The main finding was that while quantitative measures of shell color reduced the possibility of error and standardized the procedure, the same altitudinal trends were recovered, irrespective of the method. The results also showed that there was a general stability in the local shell patterns over five decades, including altitudinal clines, with just some exceptions. Therefore, although subject to potential error human scoring of snail color data remains valuable, especially if persons have appropriate training. In comparison, while there are benefits in taking quantitative measures of color in the laboratory, there are also several practical disadvantages, mainly in terms of throughput and accessibility. In the future, we anticipate that genomic methods may be used to understand the potential role of selection in maintaining shell morph clines. In addition, photographs generated by citizen scientists conducting field surveys may be used with deep learning‐based methods to survey color patterns.

Environmentally Driven Color Variation in the Pearl Oyster Pinctada margaritifera var. cumingii (Linnaeus, 1758) Is Associated With Differential Methylation of CpGs in Pigment- and Biomineralization-Related Genes.

Today, it is common knowledge that environmental factors can change the color of many animals. Studies have shown that the molecular mechanisms underlying such modifications could involve epigenetic factors. Since 2013, the pearl oyster Pinctada margaritifera var. cumingii has become a biological model for questions on color expression and variation in Mollusca. A previous study reported color plasticity in response to water depth variation, specifically a general darkening of the nacre color at greater depth. However, the molecular mechanisms behind this plasticity are still unknown. In this paper, we investigate the possible implication of epigenetic factors controlling shell color variation through a depth variation experiment associated with a DNA methylation study performed at the whole genome level with a constant genetic background. Our results revealed six genes presenting differentially methylated CpGs in response to the environmental change, among which four are linked to pigmentation processes or regulations (GART, ABCC1, MAPKAP1, and GRL101), especially those leading to darker phenotypes. Interestingly, the genes perlucin and MGAT1, both involved in the biomineralization process (deposition of aragonite and calcite crystals), also showed differential methylation, suggesting that a possible difference in the physical/spatial organization of the crystals could cause darkening (iridescence or transparency modification of the biomineral). These findings are of great interest for the pearl production industry, since wholly black pearls and their opposite, the palest pearls, command a higher value on several markets. They also open the route of epigenetic improvement as a new means for pearl production improvement.

Angiotensin I-Converting Enzyme (ACE) Inhibitory Activity of Peptides Isolated from Carabao Mango (Mangifera indica) Flesh

Hypertension has been reported as the second major cause of morbidity in the Philippines. One of the mechanisms to control blood pressure is through the inhibition of the angiotensin I-converting enzyme (ACE). This study specifically focused on the determination of ACE inhibitory activities of peptides from ‘Carabao’ mango flesh of three shell colors (SC1, SC3, SC5). The bioactive peptides were obtained upon a series of extraction, purification, and enzymatic hydrolysis steps. Among the undigested and digested crude and purified samples, the highest in vitro ACE inhibition was exhibited by the three-hour digest of SC3 (83.28 ± 0.83%). The most prominent peak from the fractionation of the mixture of peptides in SC3 digest was evaluated for ACE inhibition, and the decrease in activity inferred the synergistic effect of the peptides in exhibiting the inhibitory function. This selected bioactive peptide was revealed to have alanine and phenylalanine as the components, which can possibly be AF – an ACE inhibitory peptide determined from in silico analyses. Meanwhile, assessment of the in vivo antihypertensive activity showed no significant results due to insufficiently administered doses of the samples. Overall, the measured activity of the ACE inhibitory peptides inferred the potential of mango as a functional food in dealing with hypertension.&#x0D;

Pineapple crown and slip removal on fruit quality and translucency

The removal of pineapple crowns and slips during the final stage of fruit development can alter source-sink relationships and fruit quality. Published results have reported both positive and negative effects of both crown removal and slip removal on fruit size and quality. In this study, four treatments: control (no treatment), slips removed by hand, crown removed with a knife, and both crowns and slips removed were evaluated to clarify the effect of crown removal and slip removal on fruit quality. Crowns and slips were removed one to two months before expected harvest date, soon after slip development began. The trial was repeated three times throughout the year. Crown and slip removal had minimal effect on fruit weight, shell color and titratable acidity at harvest. Removal of the crown or removal of the crown and slips did increase total soluble solids about 1%. Removal of the crown increased translucency, though in the warm season translucency severity was low. Fruit with larger crowns had less translucency. Slip removal increased translucency slightly, but when both the crowns and slips were removed the effect on translucency severity was not additive. The results support published conclusions that crowns and artificial shade reduce translucency. A negative correlation was found between the air temperature four months before harvest at the beginning of crown growth and final crown weight. Rainfall two to four months before harvest had a significant effect on slip weight. The results suggested that crown removal can impact fruit quality and the occurrence of the fruit translucency disorder with a significant seasonal response.

Effects of oregano (Lippia origanoides) essential oil supplementation on the performance, egg quality, and intestinal morphometry of Isa Brown laying hens.

Background and Aim:The use of antibiotics as growth promoters in the feed of poultry, has contributed to an increase in the antimicrobial resistance of foodborne pathogens worldwide. Hence, the development of new effective alternatives to antibiotics that do not hinder productivity is imperative. For this, the aim of the present study was to determine whether oregano essential oil (OEO) extracted from Lippia origanoides is a suitable alternative to growth-promoting antibiotics (GPAs) for improving the performance, egg quality, and intestinal morphometry of ISA Brown laying hens.Materials and Methods:A total of ninety-six 70-week-old ISA Brown laying hens were randomly assigned to four treatment groups with four replicates per treatment and six hens per replicate. The treatments consisted of four different diets that were formulated according to the nutritional requirements of the genetic line and the production phase with and without the addition of GPA and OEO: NC, which did not contain OEO or GPA; GPA, which included 50 ppm zinc bacitracin as a GPA; 80OEO, which included 80 ppm OEO and no GPA; and 150OEO, which included 150 ppm OEO and no GPA.Results:All of the OEO and GPA treatment groups had a better feed conversion ratio than the NC group. However, the addition of 150 ppm OEO to the diet improved the percentage egg production and egg mass, as well as the external and internal quality of the egg compared with the other treatments. In addition, both the 80OEO and 150OEO treatments improved the yolk color, shell thickness, and shell color, as well as parameters related to the intestinal morphometry compared with the NC group.Conclusion:The findings of this study indicate that 150 ppm OEO can be used as a substitute for GPA to improve the performance, egg quality, and parameters related to the intestinal morphometry of ISA Brown laying hens.

Egg quality and production constraints in smallholder egg value chain of Greater Port Harcourt City, Nigeria

The study evaluated the quality of eggs and constraints facing smallholder egg producers (≤10,000 layers) in Greater Port Harcourt City, Nigeria. Desk study, survey of 47 farmers, Focused Group Discussion with eight farmers and weighing of eggs were done at Obio-Akpor, Oyigbo and Etche Municipal Councils out of the eight in Greater Port Harcourt City. Farmers were administered pre-structured questionnaires. Open questions from a checklist were used for in-depth interviews with 22 stakeholders. Thirty eggs per grade were weighed using a digital scale. Numerical data were evaluated using the SPSS statistical package, while qualitative information was assessed using matrices and content analysis. Results indicate that most farmers (56%) sort and grade their eggs for better prices but time constraint discourages others from doing so. The size was the only egg grading criterion used. A five-grade system (jumbo, extra-large, large, small, and bullet) was used. The most important quality parameters were size (41%), shell colour (29%), cleanliness (28%) and weight (2%). Customers prefer brown-shelled (82%) eggs to white (15%). Significant constraints faced by farmers were input-based (high cost and low quality feed, drug breeds, veterinary services, lack of loans); management (staff misbehaviour) and infrastructure (bad roads and poor electricity supply) related. Other stakeholders face quality challenges (small size, dirty eggs, rotting of eggs, no uniformity, low or no grading, high returns rate), financing, egg handling and marketing challenges. Proffered solutions include better chain coordination, local sourcing of eggs, improved quality control, establishment of egg aggregation centres, and introduction of machine-based grading, grade-based pricing and reduction in local production costs. Others include formation of cooperatives and bulk input purchases, improved staff motivation and better quality control. Smallholders’ access to the egg market can be improved by producing brown-shelled eggs of large, extra-large and jumbo sizes.

RAD sequencing of common whelk, Buccinum undatum, reveals fine-scale population structuring in Europe and cryptic speciation within the North Atlantic.

Buccinum undatum is a subtidal gastropod that exhibits clear spatial variation in several phenotypic shell traits (color, shape, and thickness) across its North Atlantic distribution. Studies of spatial phenotypic variation exist for the species; however, population genetic studies have thus far relied on a limited set of mitochondrial and microsatellite markers. Here, we greatly expand on previous work by characterizing population genetic structure in B. undatum across the North Atlantic from SNP variation obtained by RAD sequencing. There was a high degree of genetic differentiation between Canadian and European populations (Iceland, Faroe Islands, and England) consistent with the divergence of populations in allopatry (F ST > 0.57 for all pairwise comparisons). In addition, B. undatum populations within Iceland, the Faroe Islands, and England are typified by weak but significant genetic structuring following an isolation‐by‐distance model. Finally, we established a significant correlation between genetic structuring in Iceland and two phenotypic traits: shell shape and color frequency. The works detailed here enhance our understanding of genetic structuring in B. undatum and establish the species as an intriguing model for future genome‐wide association studies.

Phenotypic characteristics of native edible snails Achatina fulica and Archachatina marginata in equatorial region of Cameroon

Between February and May 2019, in the equatorial forest urbanized area of Cameroon (Mfoundi), a study was conducted and aimed to contribute on a better understanding of the biodiversity of edible snails for their genetic improvement and conservation. A total of 693 adult snails of two species: Archachatina marginata and Achatina fulica were collected in the various localities (Odza, Mbankolo, Biyem-assi, Nyom, Nkolbisson and Simbok). Information about biometric morpho characters was collected using a survey sheet, an electronic scale of 7000g capacity with accuracy of plus or minus 1g, a sliding foot with an accuracy of plus or minus 0.01 millimeter. A digital camera will be used for the subsequent morphological assessment of the animals. Results revealed significant influence of locality on all the morphobiometric characteristics. The shell color of A. marginata was black with yellowish stripes and the red tip was the most frequent (62.85%); while for the species A. fulica it was brown with white stripes and white tip (76.09%). The most common color of the foot in A. marginata was brown with white traces (41.70%) and in A. fulica, it was black (82.50%). The number of shell turns in A. marginata was higher in the localities of Mbankolo (5.36±0.12) and Odza (5.38±0.05) while in A. fulica it was higher in the locality of Simbok (7.41±0.49). Concerning body measurements (in mm), the total body length of A. marginata was higher in Nkolbisson (88.10±1.30) and that of A. fulica was greater in Simbok (112.25±12.16). The live weight (g) of A. marginata was higher in Mbankolo (70±0.00) on the other hand, that of A. fulica was higher in Simbok (80±0.02) and Nyom (80±0.12). The diversity observed suggests that edible snails constitutes rich natural genetic resources enough variability to envisage genetic improvement and develop preservation schemes for these snails mostly collected from wild

Experimental simulation of environmental warming selects against pigmented morphs of land snails.

In terrestrial snails, thermal selection acts on shell coloration. However, the biological relevance of small differences in the intensity of shell pigmentation and the associated thermodynamic, physiological, and evolutionary consequences for snail diversity within the course of environmental warming are still insufficiently understood. To relate temperature‐driven internal heating, protein and membrane integrity impairment, escape behavior, place of residence selection, water loss, and mortality, we used experimentally warmed open‐top chambers and field observations with a total of >11,000 naturally or experimentally colored individuals of the highly polymorphic species Theba pisana (O.F. MÜller, 1774). We show that solar radiation in their natural Mediterranean habitat in Southern France poses intensifying thermal stress on increasingly pigmented snails that cannot be compensated for by behavioral responses. Individuals of all morphs acted neither jointly nor actively competed in climbing behavior, but acted similarly regardless of neighbor pigmentation intensity. Consequently, dark morphs progressively suffered from high internal temperatures, oxidative stress, and a breakdown of the chaperone system. Concomitant with increasing water loss, mortality increased with more intense pigmentation under simulated global warming conditions. In parallel with an increase in mean ambient temperature of 1.34°C over the past 30 years, the mortality rate of pigmented individuals in the field is, currently, about 50% higher than that of white morphs. A further increase of 1.12°C, as experimentally simulated in our study, would elevate this rate by another 26%. For 34 T. pisana populations from locations that are up to 2.7°C warmer than our experimental site, we show that both the frequency of pigmented morphs and overall pigmentation intensity decrease with an increase in average summer temperatures. We therefore predict a continuing strong decline in the frequency of pigmented morphs and a decrease in overall pigmentation intensity with ongoing global change in areas with strong solar radiation.

The Structure of Causal Explanations in Population Biology.

The scope of this paper can be clarified by means of a well-known phenomenon that is usually called 'industrial melanism': the fact that the melanic form of the peppered moth became dominant in industrial areas in England in the second half of the nineteenth century. Such changes in relative phenotype frequencies are important explananda for population biologists. Apart from trying to explain such changes over time, population biologists also often try to explain differences between populations, e.g. why yellow shell colour is dominant in certain colonies of land snails and almost absent in other colonies. The causal explanations that are given to address such explananda are the objects of analysis in this paper. Our primary aim is to explicate their structure: we want to capture the typical ingredients of causal explanations in population biology, and their organisation. Based on this explication, we discuss how natural selection fits into recent mechanical philosophy of science, and engage in the debate on the nature of evolutionary theory.

The draft genome sequence of the grove snail Cepaea nemoralis

Studies on the shell color and banding polymorphism of the grove snail Cepaea nemoralis and the sister taxon Cepaea hortensis have provided compelling evidence for the fundamental role of natural selection in promoting and maintaining intraspecific variation. More recently, Cepaea has been the focus of citizen science projects on shell color evolution in relation to climate change and urbanization. C. nemoralis is particularly useful for studies on the genetics of shell polymorphism and the evolution of “supergenes,” as well as evo-devo studies of shell biomineralization, because it is relatively easily maintained in captivity. However, an absence of genomic resources for C. nemoralis has generally hindered detailed genetic and molecular investigations. We therefore generated ∼23× coverage long-read data for the ∼3.5 Gb genome, and produced a draft assembly composed of 28,537 contigs with the N50 length of 333 kb. Genome completeness, estimated by BUSCO using the metazoa dataset, was 91%. Repetitive regions cover over 77% of the genome. A total of 43,519 protein-coding genes were predicted in the assembled genome, and 97.3% of these were functionally annotated from either sequence homology or protein signature searches. This first assembled and annotated genome sequence for a helicoid snail, a large group that includes edible species, agricultural pests, and parasite hosts, will be a core resource for identifying the loci that determine the shell polymorphism, as well as in a wide range of analyses in evolutionary and developmental biology, and snail biology in general.

PERFORMANCE AND EGG QUALITY OF HENS FED COCOA HUSK BASED DIETS

Lowman Brown hens, 37 – week – old were used to study the effect of dietary inclusion of 10 and 20% cocoa husk meal (CHM) at the expense of maize on hen performance and egg quality. The trial was conducted for 10 weeks. Egg production (EP), egg weight (EW), egg mass (EM), feed consumption (FC), and feed efficiency (FC) were cost/kg egg, shell weight, percentage shell and yolk colour index. Inclusion of 10 and 20% CHM in laying hen diets had no significant effect (P &lt;0.05) on EP, EM and FE. However, FC was high appeared to be compensated for by increased egg weight. Shell weight and percent shell were not affected by dietary treatment while the 20% CHM diet increased yolk colour index. Feed cost/kg egg was lowered by feeding the test diets. The present study has shown that laying hens can tolerate and produce eggs economically on diets incorporating up to 20% CHM.

Genome-wide identification and expression profiling of TYR gene family in Ruditapes philippinarum under the challenge of Vibrio anguillarum

Tyrosinase (EC1.14.18.1, TYR) is also called phenol oxidase, is not only involved in pigmentation but also plays an important role in modulating innate immunity in invertebrates. Tyrosinase is a copper containing metalloenzyme. The tyrosinase protein has two copper binding sites and three conserved histidines. In this study, 21 tyrosinase genes (RpTYR) were obtained from the whole genome of Ruditapes philippinarum. Their open reading frames were from 951 to 5424 aa, the range of predicted relative molecular weight from 36.72 to 203.81 kDa, and the range of isoelectric point from 4.72 to 9.88. Transcriptome analysis showed that RpTYR gene was expressed specifically in different developmental stages, adult tissues, four strains and two groups with different shell colors. Besides, the expression profiles of 21 RpTYRs were investigated against the immune response of R. philippinarum to a Vibrio challenge. The qPCR results showed that RpTYRs were involved in the immune response of R. philippinarum after Vibrio anguillarum challenge. This study provides preliminary evidence that the tyrosinases genes are involved in the immune defense and the potential immune function of R. philippinarum. Overall, these findings suggested that the expansion of TYR genes may play vital roles in larval development, the formation of shell color pattern, and immune response in R. philippinarum.

Shell colour and banding polymorphism in &lt;i&gt;Cepaea nemoralis&lt;/i&gt;(Gastropoda, Pulmonata, Helicidae) from the Moscow region

The shell colour and banding were analyzed in more than 2000 specimens of Cepaea nemoralis collected in 11 localities in Moscow and the Moscow region. In the colonies studied, snails with pink shells usually predominate, most often represented by the phenotype 00000 (complete absence of the spiral bands). In most cases, yellow unbanded shells were absent or represented by single specimens. Brown shells, almost exclusively unbanded, were found only in 5 sites. On the example of colonies from Zagoryanski and Buch (Berlin), as well as Sheremetievski and Dolgoprudnyi, the phenotypic composition of newly formed colonies and colonies that could have been their origins was compared. A decrease in phenotypic diversity of newly formed colonies was noted.

Shell Banding and Color Polymorphism of the Introduced Snail Cepaea nemoralis (Gastropoda, Helicidae) in Lviv, Western Ukraine

Th e shell coloration was studied in more than three thousand adults of the grove snail, Cepaea nemoralis (Linnaeus, 1758), from 15 colonies discovered in 2019–2020 in Lviv City and in the immediate vicinity of its south-ern administrative border (Zubra village). In most colonies, relatively light phenotypes prevailed: most oft en P00000, less oft en Y00000 or Y00300. In total, more than a third of the collected specimens had the phenotype P00000. Great variability of the phenotypic and genetic structure of this introduced species in the study area was demonstrated, which usually does not have a clear connection with the locations of colonies or with the shading of habitats. Th is may be due to both random factors (founder eff ect, gene drift in recently formed colonies), and the relative youth of the colonies. In the future, the obtained data can be used to monitor possible long-term changes in the phenotypic composition of the investigated colonies to assess the potential eff ect of selective factors on this composition, fi rst of all, climatic selection outside the natural range of C. nemoralis.