THE GENUS CLITOSTETHUS WEISE (COLEOPTERA: COCCINELLIDAE) OF CHINA

In this paper, four species of the genus Clitostethus Weise from China are described, among them three species are new to science: C. acutisiphonicus, C. bawanglingensis. and C. brachylobus. A key to Chinese species of the genus Clitostethus is given.

THREE NEW SPECIES OF Scymnus KUGELANN FROM CHINA(COLEOPTERA: COCCINELLIDAE)

本文描述了小毛瓢虫属3新种:采自云南的冠端小瓢虫Scymnus(Pullus)cristiformis sp.n.,以及采自海南的匙叶小瓢虫S.(P.)scalpratus sp.n.和凹叶小瓢虫S.(P.)scrobiculatus sp.n.。模式标本存华南农业大学昆虫标本室,广州。

Lady Beetles (Coleoptera: Coccinellidae) from Pinus armandii Franchet Infested with Pineus sp.

Eighteen species of lady beetles, collected from Pinus armandii infested with Pineus sp. (Homoptera: Adelgidae), in Lijiang, Yunnan province, were enumerated, l of which was described as new to science: Scymnus (Pullus) huashansong, and l as new record for China: Adalia conglomerata (L.). Among these 18 species, 14 were also collected from the hemlocks (Tsuga dumosa, T. forrestii, and T. chinensis ) infested with the hemlock woolly adelgid ( Adelges tsugae ).

Antifeedant and insecticidal activities of selected plant extracts against Epilachna beetle, Henosepilachna vigintioctopunctata (Coleoptera: Coccinellidae)

Six different indigenous plants were screened for antifeedant and insecticidal activity against fourth instar larvae of Epilachna beetle, Henosepilachna vigintioctopunctata, which is a severe pest on brinjal. Among the plants screened, Achyranthes aspera showed higher activity against the selected pest. Ethyl acetate extracts of A. aspera showed higher antifeedant index and insecticidal activity against fourth instar larvae of H. vigintioctopunctata. Preliminary phytochemical analysis revealed that the presence of alkaloid and quinines in the ethyl acetate extracts indicate higher percentage of activities. Hence, it may suggest its use for controlling the vegetables insect pest, H. vigintioctopunctata.

Comparative Characterization of the Ladybird Beetles (Coleoptera: Coccinellidae) from Hazara University, Garden Campus, Mansehra, Pakistan

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.

SCANNING ELECTRON MICROSCOPY OF ANTENNAE OF COCCINELLA SEPTEMPUNCTATA (COCCINELLIDAE: COLEOPTERA)

Scanning electron microscopy was done to describe the morphology of antennaof adult male and fe- male ladybeetle, Coccinella septempunctata . Eleven-segmented, scaly antennawas 950μm in male and 980 μm in female. Electron micrographs reveal the occurrence of eight typesof sensillae, viz. chaetica ( Ch) , trichoidea (Tr) , basiconica (Ba) , campaniformia (Ca) ,ampucellaceous (Am) , scolopalia (Sc) , placoidea (PI) and hook shaped sensilla on the antennae ofmale and female ladybeetles. Ch had long external-process, with base surrounded by membranous socketand the length was 60 and 70 μm in male and female ladybeetle, respectively. Sensillae Tr weredistally curved and inserted into depression, 9.0 and 15 μm long in male and female ladybeetle,respectively. Sensillae Ba were cuticular peg-like and 0.57 and 0.70 μm long on the male and femaleantennae. Sensillae Ca were small dome-like and had diameter of 3.0μm in both the sexes. SensillaeAm were pit-like in appearance and the diameter of the pit was 1.2 and 1.5 in male and femaleladybeetle, respectively. Sensillae PI were elliptical sunken plates like in both the sexes.Sensillae Sc were broad at their apex and pointed at their tip, 2.5μm. A single hook-shapedsensilla of 21.0 μm in length was present on male antenna only. Ch, Ca, Am, and PI were almostsimilar in numbers in both the sexes. Sensillae Tr were more numerous on the male antenna and Bawere more numerous on the female antenna.

Effect of photoperiod on slow and fast developing individuals in aphidophagous ladybirds, Menochilus sexmaculatus and Propylea dissecta （Coleoptera： Coccinellidae）

The effects of environmental parameters on insect development have been studied extensively. But the reasons for 2 differential developmental rates within same cohort under varying environmental factors have not been explored. For the purpose, in this study the existence and stability of slow and fast development under 5 photoperiods （i.e., 8L： 16D, 10L ： 14D, 12L ： 12D, 14L ： 10D and 16L ： 8D; light and dark hours per day） and its effect on body mass and reproductive attributes in 2 aphidophagous ladybirds, Menochilus sexmaculatus （Fabricius） and Propylea dissecta （Mulsant） was examined on Aphis craccivora Koch at 27 4- 1 ~C temperature. A clear bimodal （2 peaks, where the first peak represented the fast developing and the 2nd peak slow developing individuals） pattern of distribution at each photoperiod was found. The proportion of slow and fast developing individuals in a cohort differed with photoperiods. The slow developing individuals were more in numbers at 8L ： 16D, in equal numbers at 14L ： 10D and in less numbers at 16L： 8D, indicating that the variation in emergence was owing to exogenous cues influenced differential rates of mortality. Slow developing individuals had female biased sex ratio, higher longevity and lower body mass than fast developing individuals. Fast developing females laid higher numbers of eggs with higher egg viability than slow developing females. Study of such variations in development at different photoperiods is helpful to understand its role in the development of insects particularly ladybirds and permits the selection of fast developing bioagents for their use in biocontrol of pest species.

Genetics and Characteristics of a Pigmentation Defective Laboratory Strain of the Lady Beetle, Coleomegilla maculata

Beetles in the family Coccinellidae, commonly known as ladybugs, lady beetles, or ladybirds, are easily identifiable and popular beneficial insects. Current research aims to support conservation efforts of beneficial insects in agroecosystems by exploring genetic processes related to nutrition. As a part of this research, colonies of Coleomegilla maculata have been maintained in culture and inbred over many generations since 2009. One result of this inbreeding has been the discovery of novel morphological phenotypes unique to laboratory strains or present in wild populations at such low levels that they have not yet been described. One such phenotype is described here. The strain described here, ye (yellow elytra and eyes) was characterized with classical Mendelian breeding and digital image analysis. This phenotype differs from wild populations by possessing yellow pigment in the elytra and pale grey to white eyes. In contrast, wild populations of C. maculata possess pink or red pigmented elytra with black spots, and black eyes. C. maculata is not known to exhibit polymorphism in the field. Inheritance is autosomal and recessive. This species was not previously known to exhibit the dramatic variation of color described here. The strain is stable in the homozygous recessive form, and retains laboratory rearing characteristics similar to the wild type laboratory strain.

Characteristics of a Laboratory Strain of Coleomegilla maculata with a Novel Heritable Wing Spot Pattern Trait

The lady beetle Coleomegilla maculata is a common New World insect that is naturally colored pink to red or orange with black spots on the forewings of the adult stage. Previous laboratory in-breeding resulted in selection for a strain lacking red pigment in the cuticle and eyes. An additional strain selected for a novel spotting pattern is described here. The inheritance of the new trait, “ten spotted” (10sp), was determined by classical crossing experiments. Inheritance of the trait was autosomal and exhibited incomplete dominance. Bionomic strain measurements were compared to the parental strains and were similar overall. Two expressed sequences from C. maculata that may be related to the new phenotype were compared to model insect genes encoding a melanin biosynthesis enzyme and a patterning transcription factor.

Mating behavior of an aphidophagous ladybird beetle,Propylea dissecta （Mulsant）

The mating behavior of Propylea dissecta (Mulsant) was investigated in detail.Protandry was evident, as males mature earlier than females. Predicted age of sexual maturation of male and female ladybirds was 7.12 and 9.33 days, respectively. Males performed courtship in six steps, viz. approach, watch, examine, embrace, mount and attempt. Embrace is possibly an appeasement act, while examine serves to recognize mate.Chemical signals initiate male attraction toward females. Visual and tactile cues appear to secondarily help in mate recognition. Mating lasted longest (275.40 ± 12.23 min) when it occurred between unmated individuals. It was much shorter (176.60 ± 5.60 min) when prior mated individuals copulated. There was a significant decrease in mating durations when adults were subjected to five successive matings. Fecundity and percent egg viability increased significantly with increase in the number of matings.

Evolutionary ecology of microsporidia associated with the invasive ladybird Harmonia axyridis

Invasive species are characterized by the rapid growth and spread of their populations after establishing a foothold in new habitats, and there are now many examples of such species negatively affecting biodiversity and the economy. It is unclear why some species can become successful invaders, whereas most （even if closely related） remain noninvasive. We previously proposed a hypothesis that parasites associated with invading species can promote their invasive success if they are harmless toward the invaders but harmful to their competitors and/or predators in the newly colonized habitat. Here we discuss whether microsporidia that have recently been discovered in the invasive ladybird Harmonia axyridis contribute to its invasive success. We show that all H. axyridis beetles sourced from diverse collection sites all over the world carry abundant microsporidia. This suggests that both native and invasive H. axyridis populations are associated with these tolerated parasites, which were likely to have existed in native populations before expansion rather than being acquired in newly colonized areas. We describe the pathogenesis of the microsporidia during different developmental stages of H. axyridis and we address the possibility that the predation of its infected eggs and larvae by competing native ladybird species may lead to their infection and ultimately to their decline. Finally, we discuss our initial hypothesis： microsporidia that are tolerated by an invasive vector insect can be active against susceptible native competitors and/or predator species.

INFLUENCE OF TEMPERATURE ON CERTAIN BIOLOGICAL ATTRIBUTES OF A LADYBEETLE COCCINELLA SEPTEMPUNCTA TA LINNAEUS

Influence of temperature on certain biological attributes of an aphidophagous ladybeetle, Coccinella septempunctata Linnaeus, feeding on mustard aphid, Lipaphis erysimi (Kaltenbach), at five different temperatures, viz. 20, 25, 27, 30 and 35℃ was investigated. Its developmental period was shortest (11.7±0.09days) at 35℃ and longest (20.6±0.35 days) at 20℃. Developmental rate increased with increase in temperature. Hatching percent, larval survival, adult emergence and growth index were maximum at 30℃ and minimumat 20℃. Oviposition period and fecundity were highest at 30℃ and lowest at 20℃. A positive linear relationship exists between temperature and developmental rate and negative correlation between the duration of immature life stages and temperature. The proportion of developmental period allocated to each immature stage was found to be similar at each temperature regime. Thus, 30℃ was found as the most suitable for C. septempunctata amongst the five temperatures tested.

Development and immature survival of two aphidophagous ladybirds, Coelophora biplagiata and Micraspis discolor

The developmental parameters, namely developmental periods, larval survival, adult emergence, growth index, developmental rate and sex ratio in terms of female proportion in a population of two aphidophagous ladybirds, namely, Coelophora biplagiata （Swartz） and Micraspis discolor （Fabricius） were investigated, using three aphid species as prey. The immature stages of C. biplagiata were significantly affected by prey quality and developed fastest when fed on Aphis craccivora followed by Aphis gossypii and Rhopalosiphum maidis. The order of prey suitability in terms of developmental rate of immature stages of M. discolor was just reversed. The adult females were heavier than males, while pre-pupae were heavier than pupae in both ladybirds. The sex ratio of adult emergence, though female-biased in both ladybird species, was not significantly affected by prey quality.

Gregarious pupation act as a defensive mechanism against cannibalism and intraguild predation

Coccinellid pupae use an array of defensive strategies against their natural enemies. This study aims to assess the efficiency of gregarious pupation as a defensive mechanism against intraguild predators and cannibals in coccinellid. The study was designed specifically （i） to determine the natural occurrence of gregarious pupation in the field for different coccinellid species, and （ii） to evaluate the adaptive value of gregarious pupation as a defensive mechanism against 2 types of predators （i.e., cannibals and intraguild predators）. In the field, gregarious pupation consisted of a group of 2-5 pupae. The proportion of gregarious pupation observed varied according to species, the highest rate being observed with Harmonia axyridis Pallas （Coccinellidae; 14.17%）. Gregarious pupation had no impact on the probability that intraguild predators and cannibals locate pupae. Intraguild predation occurred more often in site with gregarious pupation, while cannibalism occurred as often in site with gregarious pupation as in site with isolated pupa. However, for a specific pupa, the mortality rate was higher for isolated pupae than for pupae located in a gregarious pupation site both in the presence of intraguild predators and in the presence of cannibals. The spatial location of pupae within the group had no impact on mortality rate. Since it reduces the risk of predation, it is proposed that gregarious pupation act as a defensive mechanism for 11. axyridis pupae.