Coccinellid Species Research Articles

Aphids-induced plant volatiles affect diel foraging behavior of a ladybird beetle Coccinella septempunctata.

The ladybird beetle Coccinella septempunctata (L.) is an important biocontrol agent of pests such as various aphid species. Despite being one of the most studied coccinellid species, many aspects of its foraging behavior are still not completely understood. This study focuses on the diel foraging behavior of C. septempunctata, investigating their olfactory orientation toward aphid‐infested plants, walking activity on plants and on the soil, and feeding rates. In the scotophase the ladybird beetles were significantly more attracted to the odor of aphid‐infested plants, on which they also showed considerably higher walking activity then on uninfested controls. Females were more prone to utilize olfactory cues when searching for prey and fed at higher rates than males; this shows that they are better adapted to nocturnal activity, as they require higher food intake. Coccinella septempunctata have the same feeding rate during the scotophase as in the photophase. Our study shows that C. septempunctata has the potential to forage in the scotophase if prey is abundant. The results support the hypothesis that volatiles of aphid‐infested plants can attract or arrest foraging adult ladybird beetles, even in the darkness, which makes a considerable contribution to efficient prey search and enhances feeding capacity.

Biological Management of Aphids by Coccinellid Species

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Intraguild predation is independent of landscape context and does not affect the temporal dynamics of aphids in cereal fields

Abundance and diversity of natural enemies increases with higher landscape complexity. However, more species can also increase negative interactions such as intraguild predation (IGP), which could be detrimental to pest control. Direct observations of these trophic interactions are still lacking. In the present study, we employed DNA-based gut content analyses of coccinellid beetles to assess IGP (direct and coincidental) and aphid consumption. Species-specific and group-specific primer pairs were used to unveil the interactions of the most abundant coccinellid species, three cereal aphids and their associated parasitoids. In order to determine whether the landscape complexity promotes these interactions, we used replicated wheat fields in two contrasting landscape contexts over the season in central Chile. With higher abundance of coccinellids, we observed greater aphid consumption in complex contexts. The consumption of parasitized aphids was mostly detected early in complex contexts, suggesting a detrimental effect on the parasitoid population. Following molecular analysis, we can state that the aphids are important feeding resources for the coccinellid assemblage and are actively foraging on this important pest. Finally, this study demonstrates that direct IGP is a common interaction in this system, independently of the landscape context during the complete season. Nevertheless, the native Eriopis chilensis was found to be the most frequently consumed intraguild prey. In contrast with expected predictions, we found little evidence that the landscape context increased negative interactions, such as IGP and IGP-C and in turn that these decrease the control of Sitobion avenae.

Survey and surveillance of natural enemies in mango ecosystem

Abundance of natural enemies in mango ecosystem was studied through survey and surveillance. In order to record the natural enemies associated with mango ecosystem surveys were conducted in mango orchards in and around Malihabad block of Lucknow for two years. During the study period ten species of coccinellids and two species of chrysopid predators were recorded. The activity of lady bird beetles was noticed in mango orchard during first week of March to last week of March (10 to 13 th Standard Meteorological Week (SMW) of 2016). Lady bird beetles, Coccinella septempunctata , C. transversalis , and Menochilus sexmaculata, were found in abundance and their population counts were taken. Peak populations of coccinellids were observed during 12 th SMW with 3.3 adult beetles/panicle. Six species of parasitoids were collected from the mango ecosystem, among them; the most abundant parasitoid was Brachymeria lasus , parasitizing mango leaf webber. It was evident that wherever indiscriminate use of insecticides was undertaken, natural enemy population was very low. In unprotected orchards abundant natural enemies were recorded. In order to achieve natural control of the pest it is advised that the orchardists adopt minimal spray may be taken up.

Sublethal Effects of Four Insecticides on the Seven-Spotted Lady Beetle (Coleoptera: Coccinellidae).

To further develop integrated pest management (IPM) strategies against two sucking insect pests, Aleurocanthus spiniferus (Quaintanca) (Hemiptera: Aleyrodidae) and Toxoptera aurantii Boyer (Hemiptera: Aphididae), in Chinese tea plantations, it is important to evaluate the effects of insecticides on biological control agents, such as the seven-spot lady beetle, Coccinella septempunctata L. (Coleoptera: Coccinellidae). Therefore, we tested the toxicity and sublethal effects of spirotetramat, clothianidin, lambda-cyhalothrin, and bifenthrin on C. septempunctata. The side effects of the active ingredients of the insecticides were evaluated with residual contact tests on the larvae of C. septempunctata in the laboratory. Spirotetramat and clothianidin exhibited lower lethality to C. septempunctata as shown by the higher LC50 values and had higher selectivity for A. spiniferus and T. aurantii based on the selective toxicity ratios being superior to other tested insecticides. Spirotetramat also did not affect survival, longevity, fecundity, and egg hatching of C. septempunctata. Clothianidin and bifenthrin prolonged the duration of larval development stages of C. septempunctata obviously. Clothianidin at >2.5 mg/liter, lambda-cyhalothrin at >0.03 mg/liter, and bifenthrin at >0.125 mg/liter significantly reduced the survival and pupation rates of C. septempunctata larvae. Furthermore, spirotetramat at 3.125 mg/liter was harmless (IOBC class 1) to larvae of this coccinellid species. Based on the results, spirotetramat was innocuous to C. septempunctata larvae compared with clothianidin, lambda-cyhalothrin, and bifenthrin. Therefore, spirotetramat might be incorporated into IPM programs in combination with C. septempunctata for control of A. spiniferus and T. aurantii in the tea plantations.

Prey selection behaviour in the multicoloured Asian ladybird, Harmonia axyridis (Coleoptera: Coccinellidae)

The multicoloured Asian ladybird, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) is a generalist predator of aphids and other soft-bodied insects. Its diet leads to negative impacts on non-target species, despite its beneficial effects offered as biocontrol agent. Herein, we evaluated prey preferences and predation success of H. axyridis adults and 4th instar larvae exposed to binary prey combinations of insects commonly found in Italian vineyards. These binary combinations included a classic prey, Aphis craccivora (Hemiptera: Aphididae) and an alternative prey, i.e., first instar larvae of the European grapevine moth Lobesia botrana (Lepidoptera: Tortricidae), second instar larvae of H. axyridis, to evaluate cannibalistic behaviour of H. axyridis, fourth instar larvae of the non-target ladybird Scymnus apetzi (Coleoptera: Coccinellidae), to evaluate intra-guild predation. Results showed that H. axyridis larvae and adults can act as potential predators of the moth pest L. botrana. They were also able to predate the non-target coccinellid species S. apetzi, thus adversely affecting aphidophagous guilds. Harmonia axyridis larvae did not significantly prefer to predate A. craccivora over the other tested preys. Harmonia axyridis adults did not show significant preferences on A. craccivora over S. apetzi larvae, whereas they prefer A. craccivora over L. botrana and H. axyridis larvae. As a general trend, the prey selection time was shorter in H. axyridis larvae, if compared to adults. Overall, our study adds basic knowledge to the prey location behaviour of H. axyridis larvae and adults, showing main differences in predation parameters of larvae and adults of this species evaluating selected binary combinations of potential preys.

A Floral Diet Increases the Longevity of the Coccinellid Adalia bipunctata but Does Not Allow Molting or Reproduction

Adalia bipunctata L. (Coleoptera: Coccinellidae) is a generalist aphidophagous coccinellid and an important natural enemy in many agroecosystems including orchards. Coccinellid species have been observed to consume non-prey food like nectar and pollen, but the value of these foods for A. bipunctata is poorly known. The objective of this study was to determine the effect of different prey and non-prey diets on A. bipunctata larval development and adult longevity and fecundity. Larval development was studied on three prey diets: The aphids Dysaphis plantaginea and Myzus persicae and Lepidopteran eggs of Ephestia kuehniella; five flower diets: Matricaria chamomilla, Daucus carota, Fagopyrum esculentum, Anethum graveolens and Sinapis alba; four pollen diets from three plant species: Typha angustifolia, Malus pumila (two varieties) and A. graveolens; and 1 M solutions of three sugars: glucose, fructose and sucrose. Adult longevity and fecundity were tested on one prey diet (E. kuhniella eggs), three flower diets (F. esculentum, A. graveolens and S. alba); the same four pollen diets and three sugar diets with larvae; and finally a mixed diet of sucrose and A. graveolens pollen. A water-only (starvation) control was used for both larval development and adult longevity and fecundity. Adult lipid content was assessed as a measure of how non-prey food affects the ladybeetles’ nutritional status. Larvae did not develop beyond the first instar on any of the non-prey diets, but they lived more than twice as long as on F. esculentum and sugar diets than on water. Sugar and flower diets improved A. bipunctata adult longevity (71-92 d and 10-66d, respectively) over a pure pollen diet (6-7d). Fecundity was nil on all non-prey diets, and within a normal range on E. kuhniella eggs. The results suggest that pure floral diets do not support A. bipunctata molting or reproduction, but flowering plants can prolong A. bipunctata larval survival and adults longevity considerably when prey are absent. Adults on sugar diets had high lipid content, indicating that sugar feeding can improve overwintering survival. The findings could be used in agroecosystem design, such as the composition of flower strips for optimal functional diversity.

Big Aggregations of the Ladybird Beetles at the Mediterranean Sea Shore, Baltim, Kafr El-Sheikh, Egypt

The phenomenon of ladybird beetle (Coleoptera: Coccinellidae) aggregation was noticed during April, May and June, 2013 at the Mediterranean sea shore of Baltim city, Kafr El-Sheikh Governorate, Northern Delta, Egypt. The occurring coccinellid species were surveyed. The survey included the sandy sea shore and the adjacent vegetations; wheat, clover and weeds. Massive aggregations of the coccinellids were found along the sea coast for about 110 km, extending from Baltim city (Kafr El-Sheikh Governorate) up to Rasheed city (Beheira Governorate). Ten coccinellid species were recorded; Coccinella undecimpunctata L., C. novemnotata Herbst., C. septempunctata L.,Cydonia vicina isis Mul.,Hippodamia convergens Guerin- Meneville, H. tredecimpunctata L., H. variegata (Goeze), Hippodamia sp., Rodalia cardinalis Mul., and Scymnus spp. The phenomenon didn’t occur in year 2014 but re-occurred in year 2015 and again disappeared in 2016. The most dominant species was C. undecimpunctata (90.55 and 86.84%), followed by C. novemnotata (6.30 and 12.39%) in 2013 and 2015, respectively. All other coccinellid species were collected in little numbers. In 2013, the majority of coccinellids (46.30and 18.74%) were recorded by late April and3rd week of May, respectively. In the same year, the wheat plantations harbored 75.15%. C. septempunctata, followed by C. undecimpunctata (17.52%) and H. tredecimpunctata (6.53%). In clover, the most dominant species was C. undecimpunctata (51.71%), followed by H. tredecimpunctata (17.11%), and then Hippodamia spp. (12.63%). In weeds, C. undecimpunctata was the most occurring (42.73%), followed by Scymnus spp. (29%). In 2015, C. undecimpunctata was the most dominant in wheat, clover and weeds, with values of 90.49, 80.71 and 49.92%, respectively. C. vicina isis and Scymnus spp.were detected only in weeds

New Record and Predatory Activity of Hyperaspis campestris (Herbst 1783) (Coleoptera: Coccinellidae) on Dactylopius opuntiae (Hemiptera: Dactylopiidae) in Morocco

The Opuntia cochineal scale Dactylopius opuntiae (Cockerell) (Hemiptera: Dactylopiidae) causes severe damage to prickly pear (Opuntia sp.). This cochineal was first detected in Morocco in fall 2014 during sampling in the cactus crop in the Sidi Bennour region. In an attempt to find natural enemies that have a potential to be used as biological control agents, a team of researchers have conducted surveys in cactus production areas. In July of 2017, an unidentified coccinellid species was observed feeding actively on D. opuntiae in the Zemamra locality (Sidi Bennour, Morocco). The aim of this paper is to report the identification of this coccinellid and to confirm that D. opuntiae can be a prey of this newly recorded species. The coccinellid was identified as Hyperaspis campestris (Herbst, 1783). Under laboratory conditions, feeding habits were studied, and it was confirmed that adults of H. campestris can feed on both first and second instar of D. opuntiae. Preliminary trials showed that one adult of H. campestris consumed an average of 10 and 7.5 larvae of first and second larval instars of D. opuntiae in 24h, respectively. This is the first record of H. campestris as a biological control agent of D. opuntiae. This finding can be considered as part of an IPM program to control the wild cochineal cactus scale and reduce the pesticides used on this crop.

Differences in the Phenology of Harmonia axyridis (Coleoptera: Coccinellidae) and Native Coccinellids in Central Europe.

Harmonia axyridis (Pallas), an invasive non-native species in central Europe, can outcompete other aphidophagous species. The distribution and abundance of H. axyridis vary depending on different host plants, and its effects on native coccinellid communities may change accordingly. The distribution and abundance of coccinellids in central Europe (50°N, 14°E) were investigated from 2010 to 2016. Coccinellids were counted at regular intervals on cereals (Avena, Hordeum, and Triticum), herbaceous plants (Matricaria and Urtica) and trees (Acer, Betula, and Tilia). Additionally, the occurrence over time of each species on these plants was assessed and used as an index of persistence. Across all years, the adults and larvae of H. axyridis were the dominant species of coccinellid on trees. However, H. axyridis was less abundant on herbaceous plants and cereals than on trees. Populations of native coccinellids and H. axyridis co-occurred on trees and persisted for the same length of time, while native coccinellids persisted longer than H. axyridis on herbaceous plants and cereals. Compared to 1976-1986, in the 2010s, the abundance of native species decreased on all plants by 50-70%. The presence of H. axyridis could be considered as a factor driving changes in the assemblages of native coccinellids.

Efficacy of Two Species of Coccinellid Predators Against Four Different Aphid Pest Species at Khumaltar, Nepal

An experiment was conducted in completely randomized design (CRD) to study the efficacy and biology of two coccinellid species with four aphid species at the mass-rearing laboratory of Entomology Division, Nepal Agricultural Research Council (NARC), Khumaltar from February to May 2016. Two coccinellid species, i.e. Coccinella septumpunctata Linn. and Adonia variegate (Goeze) were given four aphid species viz; Myzus persicae (Sulzer), Lipaphis erysimi (Kaltenbach), Aphis craccivora (Koch) and Brevicorynae brassicae Linn. separately to compare the efficacy of two beetle species as effective bio-control agent. Predatory activity of C. septumpunctata was the highest on L. erysimi(feeding 183 aphids) and the lowest on A. craccivora (feeding on 126 aphids), while, that of A. variegate (Goeze) was the highest on L. erysimi (feeding 155.4 aphids) and the lowest on B. brassicae (feeding 112 aphids) during their larval stages. Fourth instar individual larval weight of C. septumpunctata was recorded the highest (26.82 mg) when fed on A. craccivora and the lowest (13.9 mg) when fed on B. brassicae, while the 4th instar larval weight of A. variegate was only 12.82 mg and 11.34mg when fed on same aphid species. Pupal and adult weight was also recorded the highest for C. septumpunctata as compared to A. variegata. Similar result was obtained for weights of adult when larvae fed on A. craccivora. The weight of female was observed relatively higher than that of male from this study for both beetle species. There was a positive correlation between predation and weight gained by larvae with respect to all aphid species. From this study, it can be concluded that C. septumpunctata seems better promising species of predators of aphids, especially beneficial in biological control of aphid species.

Conspecific and heterospecific interactions modify the functional response of Harmonia axyridis and Propylea japonica to Aphis citricola

AbstractHarmonia axyridis (Pallas) and Propylea japonica (Thunberg) (both Coleoptera: Coccinellidae) are two common aphidophagous predators that overlap in their natural niche; therefore, interactions between these two predator species could affect their overall prey consumption. The consequences of intraguild interactions on the foraging efficiency of the two coccinellid species were investigated by evaluating the functional responses of single beetles and intra‐ and interspecific combinations to densities of the spirea aphid, Aphis citricola van der Goot (Hemiptera: Aphididae), on apple seedlings, during 2 and 12 h under laboratory conditions. A type II functional response was observed in all the bioassays. Solitary H. axyridis consumed significantly more aphids than single P. japonica in both exposure periods. However, at intermediate prey densities the prey consumption of P. japonica was slightly greater than that of H. axyridis. The 95% confidence intervals of the functional response curves of conspecific and heterospecific pairs overlapped at 2 h. In contrast, conspecific pairs of H. axyridis showed a higher functional response curve at 12 h compared to a combination of H. axyridis and P. japonica. Prey's predation risk reduction was only detected for paired H. axyridis and mixed predators compared to their estimated functional responses at the 2‐h foraging period. By comparing functional responses between intraguild predatory lady beetle combinations, we could further predict the potential ecosystem service provided by these natural enemies.

Touching the Sky: Coccinellids (Coleoptera: Coccinellidae) at High Altitudes in South America.

Records of extreme altitudes where several coccinellid species from South America inhabit the Andes of Argentina, Bolivia, Chile, Colombia, Ecuador, and Peru are provided. After an intensive review of several entomological collections and literature, records for 35 species with at least one location over 3500-m elevation were obtained, including the genera Cycloneda (ten species), Eriopis (15 species and one subspecies), Harmonia (one species), Hippodamia (two species), Mimoscymnus (two species), Psyllobora (one species), and Stenadalia (four species). In total, 184 location records are listed, of which 119 were from between 3000 and 4000m, 57 between 4000 and 4900m and eight above 4900m, with the highest altitude record at 5250m for Eriopis minima Hofmann. All records above 4000m were obtained in the Puna biogeographic province within the Paramo Puneña biogeographic subregion. These records are the highest altitudes observed for the American continent and by far surpass others known for coccinellids worldwide. Several species of coccinellids living in sympatry at these high altitudes were verified, and in some cases, in situ development was inferred by the presence of immature stages. These findings are important to foresee the future effects of global warming that will affect especially the biological communities of extreme altitudes.

Factors influencing the introduction and spread of Harmonia axyridis in the Iberian Peninsula

Harmonia axyridis is a global invasive alien species and its ecological effects are well documented. However, in some regions where it was deliberately introduced, it never became fully established. Until recently, Southern Europe was one such region, although, recently several overwintering populations were found in northeast Spain, which may indicate that the species can potentially spread to the rest of the Iberian Peninsula. Besides the negative impacts for native coccinellid species, the establishment of H. axyridis in the Iberian Peninsula could have an important impact on the wine industry, which is very significant in this region. To predict if H. axyridis will be able to spread across western southern Europe, with an emphasis on vine-growing regions, we used the Mahalanobis distance presence-only species distribution model, which was constructed based on 16 bioclimatic and environmental variables to characterize the occupied niche and predict the distribution of this invasive alien species. Our model revealed that H. axyridis can find suitable conditions mostly in northern regions of the Iberian Peninsula, as well as in punctual locations, in coastal regions of this territory, including important vine-growing regions, which will constitute a challenge to producers. Until recently, the spread of H. axyridis was constrained by climatic factors such as high summer temperatures, however, the overwintering individuals found in Spain seem to be able to deal with such limitations, which apparently indicate the ability to adapt to these conditions. To prevent future negative impacts of H. axyridis in the Iberian Peninsula, we recommend the implementation of an active monitoring programme, together with local stakeholders (farmers and advisers) and citizens, to record and track the dispersion of seminal propagules, which could be more easily contained, with fewer resources.

Diversity and abundance of coccinellids (Coleoptera: Coccinellidae) on trees in parks and tree rows of Belgrade

Harmonia axyridis is an invasive coccinellid species that was first recorded in Serbia in 2008. In order to establish whether after its arrival it became the dominant coccinellid species, we investigated the diversity and abundance of coccinelids on trees in parks and tree rows of Belgrade during 2015 and 2016. Thirteen coccinellid species were recorded in these investigations. Frequently occurring among them were Adalia bipunctata, A. decempunctata, Coccinella septempunctata, Exochomus quadripustulatus, Harmonia axyridis, H. quadripunctata, Oenopia conglobata, and Popylea quatuordecimpunctata. All of them had different dynamics of appearance during the vegetation. As a result of this, the values of their dominance in the coccinellid community constantly changed. However, only in the cases of H. axyridis, O. conglobata, and C. septempunctata were those values high enough for us to be able to say that they were dominant in terms of abundance during a certain period. Although the amounts of summer precipitation in Serbia were very different during 2015 and 2016, the trends of changes in the diversity of coccinellids throughout the growing season in these two years were similar.

Flora surrounding rice fields as a source of alternative prey for coccinellids feeding on the pests of rice

Coccinellids are effective predators and a key component of the predator guild in rice ecosystems. In order to enhance their efficacy, a study was undertaken to assess the seasonal movement of coccinellids into rice fields and the role of the surrounding flora on their colonization. The seasonal abundance of coccinellids and their prey was recorded on the rice crop and the surrounding flora at fortnightly intervals from 2012 to 2015. Coccinellid prey range was assessed using PAGE electrophoresis. The herbivorous insects associated with weeds were Aphis gossypii Glover, Aphis craccivora (Koch), Cicadulina bipunctata (Melichar), Schizaphis graminum (Rondani), Sitobion sp., Thaia oryzivora Ghauri and Zygina maculifrons Matsumura. Of the species of coccinellids recorded in rice fields, Harmonia octomaculata (Fabricius), Micraspis discolor (F.), Propylea dissecta (Mulsant), Coccinella transversalis Fabricius, Cheilomenes sexmaculata (Fabricius), Scymnus nubilus Mulsant and Brumoides suturalis (Fabricius) were also recorded on weeds. The esterase profiles indicated that the leafhoppers and aphids on the weeds were the prey of the coccinellids before they colonized the rice fields. The coccinellids recorded on the weeds showed bands corresponding to the insects present on the weeds. Beetles collected from rice fields had different bands, some of which corresponded to the green leafhopper (GLH) Nephotettix virescens Distant, the brown planthopper (BPH) Nilaparvata lugens Stal and white backed planthopper (WBPH) Sogatella furcifera Hovarth infesting rice. In addition, some bands corresponded to hoppers and aphids that were present on the surrounding flora. The results indicate the importance of surrounding flora in the conservation and colonization of rice fields by coccinellids.

Biodiversity and predatory potential of coccinellids of rice ecosystems

Coccinellid species belonging to fifteen genera, under five tribes of the family Coccinellidae were collected and identified in this study. Harmonia (Fab.) was the most predominant in southern regions and Coccinella septumpunctata L. was more abundant in the northern and hill regions. Margalef richness index ranged from 9.07 to 14.00 while the species richness directly measured by Hills number H0 ranged from 5-10, with highest species richness present at Malan, Himachal Pradesh. The highest predation was observed in female H. octomaculata which fed on a maximum of 8.00, 7.42 and 6.59 brown planthopper (BPH), WBPH white backed planthopper (WBPH) and green leafhopper (GLH) respectively per day, while the lowest was observed in Propylea dissecta which fed on 3.18 to 4.50 hoppers per day. Coccinellids like H. octomaculata can be utilized in biological control programmes as a part of Integrated Pest Management to reduce pest outbreaks.

Molecular Characterization of Eye Pigmentation-Related ABC Transporter Genes in the Ladybird Beetle Harmonia axyridis Reveals Striking Gene Duplication of the white Gene.

Many species of ladybird beetles (Coccinellidae) possess vivid body colors. These colors and patterns show diversity between coccinellid species, or even within species. However, the molecular underpinnings of these striking body colors are scarcely understood. One of the candidate pigmentation molecules responsible for ladybird body color is ommochrome pigment, which is well known as the red pigment molecule responsible for the red eyes of Drosophila. Various insects also use ommochrome in body coloration. It is known that ommochrome pigment precursors are imported into appropriate cells by the ATP binding cassette (ABC) transporter proteins White and Scarlet. Thus, these ABC transporter genes are potentially involved in various color and pattern expressions seen in ladybird beetle species. In this study, in order to identify the repertory of ABC transporter genes responsible for such body colors, we performed molecular characterization of pigment-related ABC transporter genes, especially white and scarlet, in the coccinellid Harmonia axyridis. By using whole genome data for H. axyridis and subsequent RACE-PCR, six white orthologs and one scarlet ortholog were successfully identified. According to the results of functional analyses via RNA interference (RNAi), only one of these genes had a major function in eye pigmentation. Specific effects on body color and pattern were not detected by our RNAi experiments of any of these genes. This is the first report of this striking duplication of white genes and their functional analyses in insects.

Long term changes in the communities of native ladybirds in Northern Italy: impact of the invasive species Harmonia axyridis (Pallas)

Since the mid-2000s, the exotic coccinellid species Harmonia axyridis (Pallas) has established itself in Northern Italy, raising serious concerns about possible repercussions on native ladybirds. In this study we compared the ladybird assemblages in 2015–2016 with those sampled in 1995–1996, before the arrival of H. axyridis. Surveys were carried out in the same sites and with the same methods for both periods. Aphidophagous ladybirds were sampled in hedgerows and herbaceous habitats at field margins by mechanical knockdown and sweeping net, respectively. The changes in the structure of ladybird communities after the arrival of H. axyridis were significantly different between arboreal and herbaceous habitats. Harmonia axyridis is currently the dominant species in shrubs and trees, and all the native ladybird species taken together account for only approximately one third of the total individuals sampled in 2015–2016. On the other hand, the relative abundance of the exotic species in herbaceous habitats was low, and it has had a negligible relevance on the structure of ladybird communities on grasslands. Among native species, Adalia bipunctata (L.), whose ecological niche largely overlaps with that of H. axyridis, suffered the largest decline between 1995–1996 and 2015–2016. The co-occurrence of H. axyridis invasion and the regression of A. bipunctata suggest a direct impact of the exotic species, because no other major modifications occurred in the studied areas between sampling periods.

DNA barcoding evaluation and implications for phylogenetic relationships in ladybird beetles (Coleoptera: Coccinellidae)

Ladybird beetles (Coleoptera: Coccinellidae), with broad morphological diversity, wide geographic distribution and substantial agricultural significance, are a challenging group for taxonomists and phylogenetics. As a promising tool to identify and discover new species, DNA barcoding might offer significant potential for identification, taxonomy and phylogeny of ladybird beetles. In the present study, a total of 1364 COI (cytochrome C oxidase subunit I) sequences representing 128 species from 52 genera of ladybird beetles were screened for barcoding evaluation and phylogenetic analysis. Our results from the barcoding analysis revealed that COI displays a similar level of species identification efficiency (nearly 90%) either based on Kimura two-parameter (K2P) distances calculation or on simplified neighbour-joining (NJ) tree construction. The phylogenetic relationships within the family Coccinellidae was analyzed by Bayesian-inference (BI) method. The phylogenetic results confirmed the monophyly of the subfamilies Microweisinae and Coccinellinae sensu Ślipiński (2007), and suggested that the subfamilies Coccidulinae, Chilocorinae and Scymninae are paraphyletic. However, the phylogenetic relationships among different subfamilies are not clearly defined and thus remain to be thoroughly studied. Overall, our study confirmed the usefulness of DNA barcoding for coccinellid species identification and phylogenetic inference.