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Predation of Ladybird Beetles (Coleoptera: Coccinellidae) by Amphibians  [PDF]
John J. Sloggett
Insects , 2012, DOI: 10.3390/insects3030653
Abstract: Studies of predation of ladybird beetles (Coccinellidae) have focused on a limited number of predator taxa, such as birds and ants, while other potential predators have received limited attention. I here consider amphibians as predators of ladybirds. Published amphibian gut analyses show that ladybirds are quite often eaten by frogs and toads (Anura), with recorded frequencies reaching up to 15% of dietary items. Salamanders (Caudata) eat ladybirds less frequently, probably as their habits less often bring them into contact with the beetles. Amphibians do not appear to be deleteriously affected by the potentially toxic alkaloids that ladybirds possess. Amphibians, especially frogs and toads, use primarily prey movement as a release cue to attack their food; it is thus likely that their ability to discriminate against ladybirds and other chemically defended prey is limited. Because of this poor discriminatory power, amphibians have apparently evolved non-specific resistance to prey defensive chemicals, including ladybird alkaloids. Although amphibian-related ladybird mortality is limited, in certain habitats it could outweigh mortality from more frequently studied predators, notably birds. The gut analyses from the herpetological literature used in this study, suggest that in studying predation of insects, entomologists should consider specialized literature on other animal groups.
Morphological and Anatomical Studies of Floral and Extrafloral Nectaries in Some Vicia taxa (Fabaceae)  [PDF]
Samia Heneidak,A.E. Hassan
International Journal of Botany , 2007,
Abstract: Morphology and anatomy of the floral and extrafloral nectaries were studied by light and Scanning Electron Microscope (SEM) in seven Vicia taxa. The floral nectaries are diverse into three types; half-ring with ligulate nectary projections arising from its center in four taxa, a big ring without nectary projections in V. peregrina, or half-ring without nectary projections in V. ervilia and V. monantha. They are covered with several large modified nectary stomata located only near their tips in the examined species without nectary projections, or located only near their nectary projections tips in the studied species with nectary projections. These nectaries are vascularized by phloem only derived from the closet vascular traces of the staminal column to them. Most of the studied taxa showed the presence of two prominent brown spots of extrafloral nectaries on the abaxial surface of each two adjacent stipules, while absent in V. ervilia and V. monantha. They present in the middle of the stipules in V. faba and V. narbonensis, or at its base in the other studied taxa. These spots are pear-shaped in V. narbonensis, or reniform in the other taxa consisting of clavate glandular hairs densely gathering together and long or short unicellular hairs. The glandular hairs formed of a secretory head (2-4, rarely 8 cells), one stalk cell and a basal cell. Only V. peregrina is characterized by the presence of short unicellular hairs aggregated around the shallow pits edges of the nectary spots. The secretory subepidermal parenchyma consists of one layer in V. narbonensis and V. sativa subsp. cordata, two layers in V. faba and V. peregrina, or three layers in V. sativa subsp. nigra.
Interaction between ants and plants bearing extrafloral nectaries in cerrado vegetation
Oliveira, Paulo S.;Pie, Marcio R.;
Anais da Sociedade Entomológica do Brasil , 1998, DOI: 10.1590/S0301-80591998000200001
Abstract: extrafloral nectaries (efns) are nectar-secreting glands not directly involved with pollination which may occur on virtually all above-ground plant parts of angiosperms. recent studies revealed that such glands are widely distributed amongst the woody flora of the brazilian cerrados. plants bearing efns are visited day and night by a diverse assemblage of nectarivorous ants. in this review we present the data gathered during the past 15 years on the interaction between ants and efn-bearing plants in cerrado vegetation. field experiments indicate that ants visiting efns may prey or attack insect herbivores on the plant foliage, significantly reducing herbivore damage to leaves, buds or flowers. as a response, some herbivore species have developed an array of mechanisms to circumvent the ants' deterring capacities on their host plants. ant-derived benefits to plants, however, may vary with the species of visiting ant, with the defensive tactics of the associated herbivores, as well as with the plant species. we discuss the results obtained for different cerrado plant species, and suggest some promising topics for future experimental investigation.
Tree-Dwelling Ants: Contrasting Two Brazilian Cerrado Plant Species without Extrafloral Nectaries
Jonas Maravalhas,Jacques H. C. Delabie,Rafael G. Macedo,Helena C. Morais
Psyche , 2012, DOI: 10.1155/2012/172739
Abstract: Ants dominate vegetation stratum, exploiting resources like extrafloral nectaries (EFNs) and insect honeydew. These interactions are frequent in Brazilian cerrado and are well known, but few studies compare ant fauna and explored resources between plant species. We surveyed two cerrado plants without EFNs, Roupala montana (found on preserved environments of our study area) and Solanum lycocarpum (disturbed ones). Ants were collected and identified, and resources on each plant noted. Ant frequency and richness were higher on R. montana (67%; 35 spp) than S. lycocarpum (52%; 26), the occurrence of the common ant species varied between them, and similarity was low. Resources were explored mainly by Camponotus crassus and consisted of scale insects, aphids, and floral nectaries on R. montana and two treehopper species on S. lycocarpum. Ants have a high diversity on cerrado plants, exploring liquid and prey-based resources that vary in time and space and affect their presence on plants.
Nectarios Extraflorales en Piriqueta y Turnera (Turneraceae) Extrafloral nectaries in Piriqueta and Turnera (Turneraceae)  [cached]
Ana Maria Gonzalez,María Natalia Ocantos
Boletín de la Sociedad Argentina de Botánica , 2006,
Abstract: Se estudiaron los caracteres anatómicos y morfológicos de los nectarios extraflorales en 4 especies de Piriqueta , así como en 16 incluídas en 6 de las 7 series de Turnera (Turneraceae) que presentan estas glándulas. Se los clasificó de acuerdo a su forma y grado de desarrollo y se describió un nuevo tipo de "poro": foveolado. Basada en caracteres morfo-anatómicos se propuso una probable secuencia morfológica que ubicaría en una posición inferior menos especializados a las especies con nectarios extraflorales (NEF) planos y sin "poros"; luego se encuentran las especies con nectarios planos y "poros" foveolados; en posición intermedia se encontrarían los NEF elevados, tanto globosos o hemisféricos como cupuliformes; por último, están los NEF cupuliformes con "poro" crateriforme o mesetiforme. Varias especies de diversas series presentaron caracteres variables, ubicándose en posición dispar en la secuencia morfológica propuesta; también se observaron especies con caracteres heterogenéos, siendo difícil establecer su ubicación en la secuencia. The anatomical and morphological characters of the extrafloral nectaries were studied in 4 species of Piriqueta , and in 16 which belong to six of the seven series of Turnera (Turneraceae) that present these glands. They were classified according to its form and degree of development and a new type of "pore" was described: foveolate. Based on morpho-anatomical characters, a probable morphological sequence was proposed. This would locate the species with flattened EFN and without "pores" in a lower position; after that, the species with flattened nectaries and foveolate "pores" are found; in an intermediate position the elevated extrafloral nectaries (EFN) - sphericals or hemisphericals as well as cupuliforms -were found; finally, the cupuliform EFN with crateriform or mesetiform "pore" are found. Several species of diverse series presented variable characters, being located in an unlike position in the proposed morphological sequence; species with heterogeneous characters were also observed, being difficult to establish their location in the sequence.
Diversity and Distribution of Ladybird beetles (Coccinellidae) in the Cropland of Faisalabad District  [PDF]
Muhammad Nadeem Abbas, Saima Kausar and Shahnaz Akhtar Rana
International Journal of Advanced Research , 2013,
Abstract: The present study was conducted in the Faisalabad district (30° 31.5 N and 73° 74 E), Pakistan to assess diversity and distribution of ladybird beetles (Coleoptera: Coccinellidae) on five economically important crops (wheat, sugarcane, fodder, maize and vegetables) and their associated weeds. A total of 2204 specimens of coccinellids were collected belonging to four sub-families viz., Coccinellinae (n = 2076), Chilocorinae (n = 122), Epilachninae (n = 03) and Scymninae (n = 03) as well as twelve species. Fodder 57.19% (n = 1129) and wheat 37.34% (n = 737) were comprised more abundant coccinellids while sugarcane 3.04% (n = 60), vegetable 1.38% (n = 27) and maize 1.06% (n = n = 21) contribution was negligible. Fodder was also recorded more diverse (H′ = 1.541) and significantly different from all crops (p = 0.000). C. septempunctata 60.33% (n = 1191) and C. sexmaculata 19.50% (n = 385) were recorded more abundant species as well as widely distributed on all the crops. Among weeds C. dactylon 19.13% (n = 44) and F. indica 21.30% (n = 49) constituted more abundant and more diverse (H′ = 1.343, H′ = 1.115) coccinellids. It is concluded that agricultural crops and their associated weeds comprising of a variety coccinellids species, which are better control agents of insect pests.
Record of the invasive alien ladybird Harmonia axyridis (Coleoptera, Coccinellidae) from Kenya  [cached]
Old?ich Nedvěd,Ji?í Háva,Daniela Kulíková
ZooKeys , 2011, DOI: 10.3897/zookeys.106.1242
Abstract: The biological control agent and alien invasive ladybird Harmonia axyridis (Pallas, 1773) was recorded for the first time in Kenya, and in equatorial Africa, in 2010.
Comparative Characterization of the Ladybird Beetles (Coleoptera: Coccinellidae) from Hazara University, Garden Campus, Mansehra, Pakistan  [PDF]
Farzana Perveen, Anzela Khan, Hina Habib
Advances in Entomology (AE) , 2014, DOI: 10.4236/ae.2014.22011
Abstract: The ladybird beetles (Coleoptera: Coccinellidae) have great economic importance as natural enemies. Three hundred individuals belonging to 6 genera and 7 species of the subfamily, Coccinellinae and the tribe, Coccinellini was collected during March-May, 2011 from 3 study sites of Hazara University, Garden Campus, Mansehra, Pakistan. They were reported maximum (83.3%) from residential area and minimum (8%) from administration area. All collected species have glabrous hair on their slightly elongated or rounded bright colored body. The seven-spotted ladybug, Coccinella septempunctata (Linnaeus) has maximum (average: 6.7 ± 0.77 cm; n = 15) and Adalia tetraspilota (Hope) has minimum (average: 4.2 ± 0.15 cm; n = 14) body length. Moreover, transverse ladybird, Coccinella transversalis (Fabricius) has maximum (average: 4.8 ± 0.35 cm; n = 10) and Oenopia sauzeti (Mulsant) (n = 9) or adonis ladybird, Hippodamia variegate (Goeze) (n = 10) has minimum (3.1 cm) body width. Except six-spotted zigzag ladybird, Menochilus sexmaculatus (Fabricius) (n = 12), all collected species have black head, varied but attractive and dark in color pronotum and elytra, black scutellum except in fifteen-spotted ladybird, Harmonia dimidiate (Fabricius) (n = 10) which was brownish. The ventral side of body of A. tetraspilota was dark brown, however, C. septempunctata, C. transversalis, H. variegate and O. sauzeti were black; moreover, H. dimidiata was brownish-orange; further, M. sexmaculatus was brown. It is concluded that ladybird beetles of HU have great diversity. Their further studies have been needed for education and awareness.
Research progress on biology and ecology of Harmonia axyridis Pallas (Coleoptera: Coccinellidae)
异色瓢虫生物生态学研究进展

WANG Su,ZHANG Run-zhi,ZHANG Fan,
王甦
,张润志,张帆

应用生态学报 , 2007,
Abstract: Harmonia axyridis Pallas(Coleoptera:Coccinellidae)with its native in Asia is one of the most important predatory ladybird beetles,and used worldwide as a biological control agent.This paper summarized the recent decades research progress at home and abroad on its life history,reproductive strategies,and predatory and cannibalism behaviors,and analysed the prospects of its utilization.Based on the review of its artificial reproduction,insecticide interaction,and impact as an invasive species,some useful measures were suggested to prevent the beetle from its potential risk to ecological banlance.
Domacios y nectarios extraflorales en Bignoniáceas: componentes vegetales de una interacción mutualística Domatia and extrafloral nectaries in Bignoniaceae: two components of a mutualistic interaction  [cached]
Ana M Gonzalez
Boletín de la Sociedad Argentina de Botánica , 2011,
Abstract: Las plantas presentan relaciones mutualísticas con insectos a cambio del control de sus herbívoros u hongos patógenos; por medio de los domacios les ofrecen albergue y mediante la secreción de néctar de nectarios extraflorales les brindan alimento. Se examinó la anatomía foliar en 52 especies de Bignoniaceae con microscopía óptica y electrónica de barrido, con el objetivo de describir los domacios y los nectarios extraflorales. Los domacios presentes son de dos tipos: mechones de pelos y bolsillos, siendo un carácter taxonómico útil en varias especies. Los nectarios extraflorales se encuentran en todas las especies, ubicándose en diversas posiciones: a lo largo de la vena media, asociados a los domacios o agrupados en campos glandulares, que pueden ser foliares o interpeciolares. Las Bignoniaceae presentan simultáneamente domacios y nectarios extraflorales en sus hojas, los cuales se describen como componentes vegetales de un probable mecanismo de defensa indirecta. Plants have mutualistic relationships with insects in two ways: through domatia provide housing of predators, and extrafloral nectaries secreting nectar and provide food in exchange for control of herbivores or fungal pathogens. The foliar anatomy of 52 species of Bignoniaceae was examined by light and scanning electron microscopy, in order to describe the different types of domatia and extrafloral nectaries. Two types of domatia were observed: small hair-tufts and pockets; the presence and type of domatia represents important taxonomic characters in Bignoniaceae. Extrafloral nectaries are found in all studied species. They are located in different positions: along the midvein, associated with domatia, or grouped in glandular fields, either in leaf or interpetiolar. The Bignoniaceae have simultaneously domatia and extrafloral nectaries on their leaves, these features are described as plant components in a probable mechanism of indirect defense.
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