The Experts below are selected from a list of 261 Experts worldwide ranked by ideXlab platform
A C Newton - One of the best experts on this subject based on the ideXlab platform.
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Movement analyses of wood cricket (Nemobius sylvestris) (Orthoptera: Gryllidae)
Bulletin of Entomological Research, 2010Co-Authors: Niels C. Brouwers, A C NewtonAbstract:Information on the dispersal ability of invertebrate species associated with woodland habitats is severely lacking. Therefore, a study was conducted examining the movement patterns of wood cricket (Nemobius sylvestris) (Orthoptera: Gryllidae) on the Isle of Wight, UK. Juvenile (i.e. nymphs) and adult wood crickets were released and observed over time within different ground surface substrates. Their movement paths were recorded and subsequently analysed using random walk models. Nymphs were found to move more slowly than adults did; and, when given a choice, both nymphs and adults showed a preference for moving through or over leaf litter compared to bare soil or grass. A correlated random walk (CRW) model accurately described the movement pattern of adult wood crickets through leaf litter, indicating a level of directional persistence in their movements. The estimated population spread through leaf litter for adults was 17.9 cm min-1. Movements of nymphs through leaf litter could not accurately be described by a random walk model, showing a change in their movement pattern over time from directed to more random movements. The estimated population spread through leaf litter for nymphs was 10.1 cm min-1. The results indicate that wood cricket adults can be considered as more powerful dispersers than nymphs; however, further analysis of how the insects move through natural heterogeneous environments at a range of spatio-temporal scales needs to be performed to provide a complete understanding of the dispersal ability of the species.
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The influence of barriers and orientation on the dispersal ability of wood cricket (Nemobius sylvestris) (Orthoptera: Gryllidae).
Journal of Insect Conservation, 2009Co-Authors: Niels C. Brouwers, A C NewtonAbstract:Dispersal is an important process determining species spread and survival in fragmented landscapes. However, information on the dispersal ability of woodland-associated invertebrate species is severely lacking. A study was conducted examining the ability of wood cricket (Nemobius sylvestris) (Orthoptera: Gryllidae) to cross small watercourses and to orientate themselves towards habitat edges. A series of experiments were conducted where juvenile (i.e. nymph) and adult wood crickets were released and observed over time. The results of this investigation indicated that (i) nymphs and adults were equally able to swim across a small (≤35 cm) watercourse; and (ii) adult wood cricket were able to positively orientate themselves towards a mature woodland edge at a visual angle of ≥19°, when less than 50 m away. Together, this investigation suggests that these traits likely facilitate the ability of this species to disperse within fragmented wooded landscapes, however, further study is needed to strengthen the significance of these findings for this and similar species.
Joan Cottrell - One of the best experts on this subject based on the ideXlab platform.
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development of microsatellite markers for the wood cricket nemobius sylvestris orthoptera Gryllidae
Molecular Ecology Resources, 2008Co-Authors: Tytti Vanhala, Joan CottrellAbstract:: Thirty-four novel microsatellite markers developed for wood cricket (Nemobius sylvestris) were tested and optimized. Twenty-five microsatellite loci were polymorphic, exhibiting between two and nine alleles. Observed heterozygosities ranged from 0.038 to 0.925. The microsatellites were also tested in a species belonging to another genus of the Gryllidae family (Gryllus bimaculatus). Two markers produced clear banding patterns with the expected product size. These markers will be used to study the effects of forest fragmentation on genetic connectivity using wood cricket as a model species.
Niels C. Brouwers - One of the best experts on this subject based on the ideXlab platform.
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Movement analyses of wood cricket (Nemobius sylvestris) (Orthoptera: Gryllidae)
Bulletin of Entomological Research, 2010Co-Authors: Niels C. Brouwers, A C NewtonAbstract:Information on the dispersal ability of invertebrate species associated with woodland habitats is severely lacking. Therefore, a study was conducted examining the movement patterns of wood cricket (Nemobius sylvestris) (Orthoptera: Gryllidae) on the Isle of Wight, UK. Juvenile (i.e. nymphs) and adult wood crickets were released and observed over time within different ground surface substrates. Their movement paths were recorded and subsequently analysed using random walk models. Nymphs were found to move more slowly than adults did; and, when given a choice, both nymphs and adults showed a preference for moving through or over leaf litter compared to bare soil or grass. A correlated random walk (CRW) model accurately described the movement pattern of adult wood crickets through leaf litter, indicating a level of directional persistence in their movements. The estimated population spread through leaf litter for adults was 17.9 cm min-1. Movements of nymphs through leaf litter could not accurately be described by a random walk model, showing a change in their movement pattern over time from directed to more random movements. The estimated population spread through leaf litter for nymphs was 10.1 cm min-1. The results indicate that wood cricket adults can be considered as more powerful dispersers than nymphs; however, further analysis of how the insects move through natural heterogeneous environments at a range of spatio-temporal scales needs to be performed to provide a complete understanding of the dispersal ability of the species.
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The influence of barriers and orientation on the dispersal ability of wood cricket (Nemobius sylvestris) (Orthoptera: Gryllidae).
Journal of Insect Conservation, 2009Co-Authors: Niels C. Brouwers, A C NewtonAbstract:Dispersal is an important process determining species spread and survival in fragmented landscapes. However, information on the dispersal ability of woodland-associated invertebrate species is severely lacking. A study was conducted examining the ability of wood cricket (Nemobius sylvestris) (Orthoptera: Gryllidae) to cross small watercourses and to orientate themselves towards habitat edges. A series of experiments were conducted where juvenile (i.e. nymph) and adult wood crickets were released and observed over time. The results of this investigation indicated that (i) nymphs and adults were equally able to swim across a small (≤35 cm) watercourse; and (ii) adult wood cricket were able to positively orientate themselves towards a mature woodland edge at a visual angle of ≥19°, when less than 50 m away. Together, this investigation suggests that these traits likely facilitate the ability of this species to disperse within fragmented wooded landscapes, however, further study is needed to strengthen the significance of these findings for this and similar species.
Zhuqing He - One of the best experts on this subject based on the ideXlab platform.
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a new genus of cricket with one new species from western yunnan china orthoptera Gryllidae gryllinae
Zootaxa, 2019Co-Authors: Chuze Shen, Ling Zhang, Zhuqing HeAbstract:Most male crickets can produce songs mostly for attracting females. Songs are specific among species,. this depending on physiology and the structural characteristics of the forewings. Nevertheless, some species belonging to subfamily Gryllinae have lost their singing abilities (mute species). Chinese examples include Agryllus spp., Conoblemmus spp., Goniogryllus spp. and Callogryllus yunnanus . Males of these genera are either wingless or have forwings similar to those of females. These crickets have been poorly studied in China. In this study, we describe one new genus Asonicogryllus He gen. nov. with a new species Asonicogryllus kwanghua sp. nov. from western Yunnan. The type specimens are deposited in Museum of Biology, East China Normal University (ECNU).
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a phylogenetic study of chinese velarifictorus randell 1964 based on coi gene with describing one new species orthoptera Gryllidae gryllinae
Zootaxa, 2018Co-Authors: Guangyu Chen, Chuze Shen, Wang Liao, Zhuqing HeAbstract:Eight species of genus Velarifictorus Randell, 1964 have been recorded from China prior to this study. Here we describe one new species, Velarifictorus dianxiensis He sp. nov. from western Yunnan. COI genes of Velarifictorus spp. were used to reconstruct a phylogenetic tree for confirming the relationships of these species. The type specimens are deposited in Museum of Biology, East China Normal University (ECNU).
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a new species of teleogryllus teleogryllus chopard 1961 from yunnan china orthoptera Gryllidae gryllinae
Zootaxa, 2018Co-Authors: Chuze Shen, Yue Xu, Guangyu Chen, Zhuqing HeAbstract:There are six species of genus Teleogryllus Chopard, 1961 recorded from China prior to this study. They belong to either subgenus Macroteleogryllus or subgenus Brachyteleogryllus . We describe a new species, Teleogryllus ( Teleogryllus ) albipalpus He sp. nov. belonging to subgenus Teleogryllus from Yunnan, China. The morphology of adults and nymphs in different instars, songs and COI gene are provided. The type specimens are deposited in Museum of Biology, East China Normal University (ECNU).
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Seasonal and geographical adaption of two field crickets in China (Orthoptera: Grylloidea: Gryllidae: Gryllinae: Teleogryllus ).
Zootaxa, 2017Co-Authors: Zhuqing He, Xiaoyin Wang, Kai LiAbstract:Crickets of the genus Teleogryllus belong to Gryllidae, Orthoptera. Teleogryllus emma (Ohmachi and Matsumura) and T. occipitalis (Serville) are widely distributed in east Asia, but their distribution and life history have not been reported from China. We studied the seasonal and geographical adaptation by rearing these crickets and measuring specimens. The main results are as follows: T. emma belongs to short-day type, which means nymphs grow rapidly in short day conditions (LD 12:12); T. occipitalis belongs to long-day type, which means nymphs grow rapidly in long day conditions (LD 16:8). The nymphal growth rate accelerates with the increase of temperature by comparing their nymph developmental period at 25 and 30 O C. T. emma is mainly distributed in the north of the Yangtze River, while T. occipitalis in the south of it. The body size decreases with the increase of latitude in both species, while the relative length of their ovipositor increases.
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The influence of developmental days on body size and allometry of head width in male Loxoblemmus angulatus (Orthoptera: Gryllidae)
Canadian Entomologist, 2014Co-Authors: Zhuqing He, Makio TakedaAbstract:Male crickets belonging to the genus Loxoblemmus Saussure (Orthoptera: Gryllidae) often exhibit exaggerated facial structures with characteristic projections. Whether these structures are stable within a single species is not certified. We collected Loxoblemmus angulatus Bey-Bienko and reared the secondgenerationunder 16:8, 14:10, and12:12light:darkphotoperiods. Bodymorphologyofadults was measuredanddevelopmentdayswererecorded.Theresultsshowedthatshortdaytimephotoperiodmade them develop slowly. Males became larger after longer developmental days. Head width was wider in males and horns on head were more exaggerated in large individuals than in small ones. Head width was allometric against pronotum width. Our study shows that the male head morphology in L. angulatus is strongly influenced by development days and it is not suitable as taxonomic characters. Resume—Les grillons mâles appartenant au genre Loxoblemmus Saussure (Orthoptera: Gryllidae) portent souvent des structures faciales demesurees avec des projections caracteristiques. Il n'est pas prouve que ces structures soient stables au sein d'une meme espece. Nous avons recolte des L. angulatus Bey-Bienko et avons eleve la seconde generation sous des photoperiodes de 16:18, 14:10 et 12:12 heures de lumiere:obscurite. Nous avons mesure la morphologie corporelle et note la duree du developpement en jours. Nos resultats montrent que la photoperiode de jours courts ralentit le developpement. Le mâles atteignent une plus grande taille lorsqu'ils sont eleves dans des conditions de jours longs. La largeur de la tete est plus grande chez les mâles et les cornes cephaliques plus demesurees chez les grands individus que chez les petits. Il y a une relation d'allometrie entre la largeur de la tete et la largeur du pronotum. Notre etude demontre que la morphologie de la tete du mâle chez L. angulatus est fortement influencee par la longueur du jour pendant le developpement et que ce n'est donc pas la un caractere taxonomique approprie.
H C Gerhardt - One of the best experts on this subject based on the ideXlab platform.
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reproductive isolation in the wood cricket gryllus vernalis orthoptera Gryllidae
Ethology, 2007Co-Authors: Y Jang, Amanda Bockhorst, H C GerhardtAbstract:Two species of closely related wood crickets, Gryllus vernalis (Orthoptera: Gryllidae) and G. fultoni, occur together in the eastern USA and have a similar calling-song structure, consisting of three-pulse chirps. Previous studies revealed that male calling song and female selectivity were divergent between sympatric and far allopatric populations of G. fultoni, consistent with the pattern expected of reproductive character displacement. We studied the reproductive isolation of G. vernalis in relation to G. fultoni by investigating the geographic variation in calling songs of G. vernalis and by examining close-range mating behaviors. Neither field nor laboratory studies revealed differences in any of the calling-song characters between sympatric and allopatric populations, but this could reflect the limited sampling within the relatively small region of allopatry for G. vernalis. Although close-range mating trials revealed that females of both species discriminated against heterospecific mating partners, the strength of discrimination was especially strong in females of sympatric G. vernalis populations. Our studies of long-range and close-range mating behaviors suggest that selection pressures for reproductive isolation are exerted primarily on close-range mating behaviors in G. vernalis but on long-range mating behaviors in G. fultoni.
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divergence in the calling songs between sympatric and allopatric populations of the southern wood cricket gryllus fultoni orthoptera Gryllidae
Journal of Evolutionary Biology, 2006Co-Authors: Y Jang, H C GerhardtAbstract:In the eastern United States the wood cricket Gryllus fultoni (Orthoptera: Gryllidae) occurs in sympatry with G. vernalis in an area between eastern Kansas and west of the Appalachian Mountains. Calling songs were recorded from 13 sympatric and allopatric localities. Both field and laboratory recordings showed that chirp rate (CR) and pulse rate (PR) overlapped extensively between allopatric populations of G. fultoni and sympatric populations of G. vernalis; by contrast, there was little or no overlap in these variables between sympatric populations of these two species. Divergence in PR and CR between the two species was thus greater in areas of sympatry than in areas of allopatry. Our field and laboratory studies of G. fultoni calling songs thus demonstrate the pattern expected of character displacement and support the genetic assumptions of this hypothesis. Other possible explanations for the sympatric divergence such as ecological character displacement and clinal variation are discussed.
