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1.
Studies on population dynamics and vertical distribution in the soil of Scaptocoris carvalhoi Becker were carried out in a pasture area in Paraúna, State of Goias, Brazil, from November 2004 to October 2005. One meter-deep holes were excavated in the soil, except on the season of lower precipitation, when 2-meter holes were excavated (June, August and September 2005). On each evaluation, the specimens were collected and grouped according to the depth they were found in the soil profile (0-20, 21-40, 41-60, 61-80 and 81-100 cm). Nymphs occurred during the entire length of the study and were more abundant than adults. Adult population augmented with the increase of rainfall. Nymphs and adults were located in the top layer of the soil during the rainy season and were found deeper in the soil during droughts. However, adults were less tolerant to hydric stress and burrowed deeper into the soil at the beginning of the dry season, while nymphs burrowed deeper only at the end of the season. Results of this study are in accordance to other studies on various species of Scaptocoris, in other regions of Brazil.  相似文献   

2.
Neem (Azadirachta indica) seedlings were found infested by the brown burrower bug, Scaptocoris castanea Perty, in December 2009, in the county of Tupaciguara, Minas Gerais state. Symptoms observed varied from leaf yellowing and stem drying, reduction in root size and number to plant death. This is the first report of S. castanea attacking neem plants.  相似文献   

3.
Characters of immatures are potentially useful in identifying taxa, but few immatures of Pentatomidae were described. The objectives here are to describe the egg and five nymphal instars of Caonabo pseudoscylax (Bergroth) under light and scanning electron microscopy. Adults, eggs, and nymphs were collected on Homolepsis glutinosa during 2008, in Criciúma (Santa Catarina, Brazil). The egg of C. pseudoscylax is subcylindrical, chorion reddish brown, slightly translucent, and with granulate surface. Aero-micropylar processes translucent, spongy, and strongly clavate. Nymphs without punctures, spiracles placed near the lateral abdominal margin. The dorsal abdominal gland has rounded ostioles bearing cuticular valve; spout peritreme smooth, directed anteriorly; evaporatorium network-shaped; and microsculpture poorly ornamented. Humeral angles of the pronotum were produced from fourth instar. The almost marginal placement of abdominal spiracles may diagnose the nymphs of C. pseudoscylax from first instar to adulthood.  相似文献   

4.
We observed the seed-carrying and feeding behavior of a stink bug, Adrisa magna, under manipulated conditions in the laboratory. The bugs were most active at night but also fed on seeds under shelter during the daytime. When adults were housed on their own, they often left these shelters with the seeds in them and reused the abandoned seeds later. When several adults were introduced into a container, we found adults feeding communally and sucking on seeds abandoned by other bugs. It is suggested that seed-carrying behavior allows for communal feeding between conspecific bugs in heterogeneous environments. Received: April 19, 1999 / Accepted: May 22, 2000  相似文献   

5.
Aspisoma lineatum (Gyllenhal) is a common firefly in the Southeastern region of Brazil. Adults and larvae were collected in the municipality of Campinas, state of S?o Paulo, Brazil, and the immature stages were described and reared in the laboratory. Four generations were reproduced in the laboratory, and a method for its rearing was established. The life cycle usually lasts 6?months, but under optimal laboratory conditions, it lasted from 2 to 4?months. Larvae were fed with Bradybaena similaris and Bulimulus tenuissimus snails since the beginning of the larval stage. This species was found to be easily adapted to environments under anthropic influence, such as urban areas and farms.  相似文献   

6.
Tibial combs in representatives of the family Cydnidae are described in detail for the first time. The structure was studied in 98 species of 58 genera representing all the subfamilies, among them 16 species were investigated using scanning electron microscopic (SEM) techniques. In addition, Parastrachia japonensis (Scott, 1880) of the family Parastrachiidae, and two species of Dismegistus Amyot and Serville, 1843 (a genus of uncertain systematic position within Pentatomoidea) have also been studied. Morphological terminology is proposed for all the structures connected with tibial combs and the term 'the tibial comb complex' is suggested; its functional, taxonomic and phylogenetic significance is also discussed. The genera of Cydnidae can be classified into two groups depending on differences in the tibial comb complex, when it is present; moreover, its absence in the tribe Scaptocorini (Cephalocteinae) is demonstrated for the first time and is regarded as an autapomorphy of this tribe. Data on the occurrence of tibial combs in other families of true bugs (Hemiptera: Heteroptera) are also briefly reviewed, and an anagenetic trend in their evolution in terrestrial Heteroptera is hypothesized. The presence of tibial combs on all legs is regarded as the most plesiomorphic state.  相似文献   

7.
Females of Parastrachia japonensis (Hemiptera: Cydnidae) provision nymph-containing nests with drupes of the single host tree, Schoepfia jasminodora (Rosidae: Santales). P. japonensis feeds on the endosperm of these drupes. Foraging females approached and accepted only a few selected drupes for transport to their nests from among the hundreds of drupes scattered on the ground. The characteristics of the drupes that elicited an acceptance response under field conditions were examined. Females estimated the degree of endosperm development using volatile and nonvolatile chemicals in the outer skin as cues and selected only those drupes which had a well-developed endosperm. Although the cues that prompted approach and inspection of a drupe are in the fleshy outer skin, females presented with various substitute drupes coated with outer skin juices of acceptable drupes selected only those they could recognize as a solid mass, suggesting that they used volatile chemicals in the outer skin as cues for approaching and inspecting a drupe and then taste and tactile stimuli as cues for acceptance. Thus, this bug possesses a complex, ecologically sensitive cognitive system that enables it to recognize valuable food items by using reliable cues. The importance of selective foraging by P. japonensis females and the evolutionary significance of this behavior are discussed.  相似文献   

8.
Adults and nymphs of Chinavia erythrocnemis (Berg) were colected on Sebastiania commersoniana (Baill.) Smith & Downs in the Parque Estadual do Espinilho in Barra do Quarai county, RS, and used to establish a laboratory culture reared on green pods of Phaseolus vulgaris L. Egg coloration is light-brown, chorion is reticulated and aero-micropylar processes are clubbed and white; mean number of aero-micropylar processes is 61. Eggs are very similar to those from other Neotropical Chinavia species, but the average number of 12 eggs/mass is unique among Chinavia species. Nymphs are predominantly black, with the distal part of the head, femur, and the basal part of tibia, red. First instar has the dorsal maculae of the head and thorax in red coloration, and the abdomen with a series of 3+3 dorsal white maculae. Second to fifth instars have 1+1 white maculae on lateral margins of pronotum and 2+2 white maculae on abdome. Fourth and fifth instars show an ovate white maculae in the middle of lateral plates of abdomen. Nymph coloration and the size, number and position of the maculae on pronotum and abdomen are diagnostic to C. erythrocnemis.  相似文献   

9.
The hypothesis that cyanogenic potential in cassava is a defense mechanism against arthropod pests is one of the crucial questions relevant to current efforts to reduce or eliminate cyanogenic potential (CNP) in cassava. The generalist arthropod Cyrtomenus bergi, which attacks cassava roots, was used in a bioassay relating oviposition and survival to CNP, concentration of nonglycosidic cyanogens, and linamarase (beta-glycosidase) activity in twelve selfed cassava siblings and their parental clone, which has segregated for different levels of cyanogenesis. Electron microscopic evaluation revealed an intracellular pathway of the stylet of C. bergi in the cassava root tissue to rupture cell walls. This feeding behavior causes cyanogenesis and increased linamarin content in the hemolymph of C. bergi while feeding on a cyanogenic diet. This diet resulted in a significant reduction in oviposition, especially at levels of CNP above 150 ppm (expressed as hydrogen cyanide) on fresh weight basis (or 400 ppm on dry weight basis) in cassava roots. An exponential decline in oviposition was observed with increasing levels of CNP, beginning 12 d after exposure to the cyanogenic diet. Cyanogenic potential and dry matter content showed a positive effect on survival. No relationship was found between concentrations of nonglycosidic cyanogens or linamarase activity in the cassava root and either oviposition or survival. According to our results, there is a significant difference between potentially noncyanogen and high cyanogen clones, but there may not be a significant difference between potentially noncyanogen and low cyanogen clones. Consequently, more frequent outbreaks or higher levels of damage might not be anticipated in potentially noncyanogen cassava clones than that anticipated in low cyanogenic clones. The negative effect of cyanogenesis on oviposition concurrent with a positive effect on survival of this pest is most likely the result of a physiological trade-off between survival and oviposition. The question of whether ovipositional rates could be recovered after a long-term exposure to cyanide remains unanswered.  相似文献   

10.
The duration of copulation in the gregarious shield bug, Parastrachia japonensis Scott (Hemiptera: Cydnidae), is of two types, the far more prevalent short-term copulation (average, 15 s) and the long-term coupulation (average, 23 min). Both types were thought to be equally effective in inseminating females. Recent evidence has suggested that there is, in fact, a discrepancy in insemination success between the two duration types of copulations. We carried out manipulated field studies to clarify the difference in insemination success between the two duration types and to determine whether there is some physical or physiological variability in females or males that might affect female receptivity to a long-term copulation. The findings indicated that, although a small percentage of short-term copulations resulted in some sperm transfer, long-term copulations were a far more effective way for males to inseminate females. Further, females experiencing long-term copulations were found to be at a slightly more advanced stage of ovarian development than those experiencing only short-term copulations, and may be deciding whether a long-term copulation occurs. Male size does not appear to affect copulation duration. It is concluded that the long-term type of copulation is the actual effective copulation duration in this species and the objective of all females. Possible factors that might contribute to the prevalence of these two copulation durations are discussed. Received: June 21, 1999 / Accepted: September 6, 1999  相似文献   

11.
The immatures stages of 8 of the 11 genera (Amastris Stål, Bajulata Ball, Erosne Stål, Harmonides Kirkaldy, Idioderma Van Duzee, Neotynelia Creão-Duarte & Sakakibara, Tynelia Stål, and Vanduzea Goding) of the tribe Amastrini are described for the first time along with brief diagnoses of Membracidae and the subfamily Smiliinae. A key to genera and notes on biology are provided. Multiple species of most genera are illustrated. Based on its distinct nymphal morphology, Vanduzea laeta nolina Ball is elevated to specific rank as Vanduzea nolina stat. n., and Bajulata, despite the superficial similarity of its adults to those of Vanduzea, is confirmed as warranting generic rank based on its unique nymphal morphology. Colombia is a new country record for Tynelia.  相似文献   

12.
The hypothesis that cyanogenic potential in cassava roots deters polyphagous insects in the field is relevant to current efforts to reduce or eliminate the cyanogenic potential in cassava. To test this hypothesis, experiments were conducted in the field under natural selection pressure of the polyphagous root feeder Cyrtomenus bergi Froeschner (Hemiptera: Cydnidae). A number of cassava varieties (33) as well as 13 cassava siblings and their parental clone, each representing a determined level of cyanogenic potential (CNP), were scored for damage caused by C. bergi and related to CNP and nonglycosidic cyanogens, measured as hydrogen cyanide. Additionally, 161 low-CNP varieties (< 50 ppm hydrogen cyanide, fresh weight) from the cassava germplasm core collection at Centro Internacional de Agricultura Tropical (CIAT) were screened for resistance/tolerance to C. bergi. Low root damage scores were registered at all levels of CNP. Nevertheless, CNP and yield (or root size) partly explained the damage in cassava siblings (r2 = 0.82) and different cassava varieties (r2 = 0.42), but only when mean values of damage scores were used. This relation was only significant in one of two crop cycles. A logistic model describes the underlying negative relation between CNP and damage. An exponential model describes the underlying negative relation between root size and damage. Damage, caused by C. bergi feeding, released nonglycosidic cyanogens, and an exponential model fits the underlying positive relation. Fifteen low-CNP clones were selected for potential resistance/tolerance against C. bergi.  相似文献   

13.
South American Pipidae show a unique reproductive mode, in which the fertilized eggs develop in temporarily formed brood chambers of the dorsal skin after eggs have been deposited on the back of the female. We studied the skin incubation of Pipa carvalhoi using light microscopy and scanning electron microscopy. The skin consists of a stratified epithelium with a one‐layered stratum corneum, and the dermis. The dermis of the dorsal skin of nonreproductive and reproductive females lacks a distinct stratum compactum, which is typical for most anuran skins. The entire dermis shows irregularly arranged collagen bundles like a stratum spongiosum. Before egg laying, the skin swells, primarily by thickening and further by loosening of the middle zone of the dermis. In the epidermis, large furrows develop that are the prospective sites of egg nidation. The epidermis, which forms a brood chamber around the developing egg becomes bi‐layered and very thin and lacks a stratum corneum. Further, the dermis loosens and becomes heavily vascularized. Egg carrying females do not have mature oocytes in their ovaries indicating a slow down or interruption of egg maturation during this period. Similarities with the brood pouch of marsupial frogs are discussed. J. Morphol., 2009. © 2009 Wiley‐Liss, Inc.  相似文献   

14.
Syncarpiolyma Froggatt and its type species S. maculata Froggatt are revised. A second species, Syncarpiolyma maculatipennis sp.n., is described from four females collected in Queensland and New South Wales.  相似文献   

15.
A new trypanosomatid species, Blastocrithidia cyrtomeni, is herein described using morphological and molecular data. It was found parasitising the alimentary tract of the insect host Cyrtomenus bergi, a polyphagous pest. The morphology of B. cyrtomeni was investigated using light and transmission microscopy and molecular phylogeny was inferred from the sequences of spliced leader RNA (SL rRNA) - 5S rRNA gene repeats and the 18S small subunit (SSU) rRNA gene. Epimastigotes of variable size with straphanger cysts adhering to the middle of the flagellum were observed in the intestinal tract, hemolymph and Malpighian tubules. Kinetoplasts were always observed anterior to the nucleus. The ultrastructure of longitudinal sections of epimastigotes showed the flagellum arising laterally from a relatively shallow flagellar pocket near the kinetoplast. SL RNA and 5S rRNA gene repeats were positive in all cases, producing a 0.8-kb band. The amplicons were 797-803 bp long with > 98.5% identity, indicating that they originated from the same organism. According to the sequence analysis of the SL-5S rRNA gene repeats and the 18S SSU rRNA gene, B. cyrtomeni is different from all other known species or isolates of Trypanosomatidae. Both analyses indicate that among known species, it is most closely related to Blastocrithidia triatomae.  相似文献   

16.
Cydnidae are defined as those Pentatomoidea with setal combs at the apices of the coxae and a strigil on the ventral surface of the metathoracic wing. Eight subfamilies are recognized: Thaumastellinae, Amnestinae, Cydninae, Scaptocorinae, Sehirinae, Garsauriinae, Thyreocorinae (including only Thyreocoris, Carrabas and Strombosoma) and Corimelaeninae. Eumetopia is included in Corimelaeninae. Dismegistus is excluded from Cydnidae.  相似文献   

17.
巴大叶蝉属Bharagonalia全世界已知24种,分布于东洋区,中国仅记载1种,即巴大叶蝉Bharagonalia yalma Young,1986。通过解剖,详细描述了该种类雌、雄外生殖器特征,绘制了雌、雄外生殖器构造图,提供了成虫背面、侧面和腹面的彩色照片。本文首次对巴大叶蝉属种类雌性外生殖器进行了详细描记,并且与其近似属凹大叶蝉属Bothrogonia就雌性外生殖器作了特征比较。  相似文献   

18.
19.
《Journal of Asia》2014,17(1):59-61
A new species, Tanna aquilonia sp. nov., is described from Xinjiang Uygur, China, which is the northernmost locality ever recorded for the genus Tanna Distant, 1905. Fuscous patch on inner one-third of the timbal cover and the considerably bent uncus can distinguish this species from its congeners. A short discussion about the taxonomic status of Tanna and Neotanna Kato, 1927 as a junior synonym is provided.  相似文献   

20.
This paper describes a new Ortheziolamameti species from the Oriental region (India), namely Ortheziolamameti tranfagliai Konczné Benedicty, sp. n. The examined material was extracted from forest litter from India, using Berlese funnels. With this new species the genus Ortheziolamameti now includes six species. An identification key and distribution map are provided.  相似文献   

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