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1.
The complete larval development of the shallow-water Caribbean porcellanid crab, Petrolisthes politus (Gray, 1831), is described and illustrated from specimens reared in the laboratory. Petrolisthes politus hatches as a prezoea, which persist for less than 90 minutes, and then molts through two subsequent zoeal stages, which are completed in 6 to 7 and 14 to 16 days, respectively, before the megalopal stage is reached. From a total of about 2000 zoeae that were cultured, only two reached the megalopal stage. The two megalopae survived for up to 5 days but did not molt to the first crab stage. The zoeae of P. politus are compared with those of Petrolisthes rufescens (Heller, 1861), Petrolisthes lamarckii (Leach, 1820), Petrolisthes carinipes (Heller, 1861), Petrolisthes coccineus (Owen 1839) and Petrolisthes pubescens (Stimpson, 1858), which were hitherto the only species having bifid lateral spines on the telson of the first zoeal stage.  相似文献   
2.
The first overview on the Auchenorrhyncha fauna of peat bogs of the Austrian Bohemian Forest is presented. Seven oligotrophic peat bog sites were studied in 2011 by suction sampler (“G-Vac”) and 93 Auchenorrhyncha species (with 7465 adult specimens) were recorded. Eleven species (about 18 % of the individuals) are tyrphobiontic or tyrphophilous. The relative species abundance plot is not very steep; the six most abundant species represent 50 % of the individuals. The most common species is Conomelus anceps (17 % of the individuals). Compared to the whole Austrian Auchenorrhyncha fauna, the fauna of peat bogs comprises distinctly more univoltine species and more species hibernating in nymphal stage. Densities of adult Auchenorrhyncha in peat bogs are low in spring (about 10–60 individuals per m²) and high in July, with up to 180 (±50) individuals per m². Disturbed peat bogs have higher species numbers and higher Auchenorrhyncha densities in total, but lower numbers and densities in peat bog specialists.  相似文献   
3.
Paraportanus longispinus,, a new leafhopper species from Roraima and Amazonas States, North Brazil, is described and illustrated. The new species can be recognized by the male genital features, especially the distal third of ventral margin of the pygofer with a dentiform short process; plates distinctly longer than pygofer, extending posteriorly beyond pygofer by approximately 1/3 of their length and aedeagus with one pair of spiniform process long crossed and directed ventrally. A checklist and key to males of all known Paraportanus species is provided.  相似文献   
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5.
Bacterial symbionts that undergo long-term maternal transmission experience elevated fixation of deleterious mutations, resulting in massive loss of genes and changes in gene sequences that appear to limit efficiency of gene products. Potentially, this dwindling of symbiont functionality impacts hosts that depend on these bacteria for nutrition. One evolutionary escape route is the acquisition of a novel symbiont with a robust genome and metabolic capabilities. Such an acquisition has occurred in an ancestor of Philaenus spumarius, the meadow spittlebug (Insecta: Cercopoidea), which has replaced its ancient association with the tiny genome symbiont Zinderia insecticola (Betaproteobacteria) with an association with a symbiont related to Sodalis glossinidius (Gammaproteobacteria). Spittlebugs feed exclusively on xylem sap, a diet that is low both in essential amino acids and in sugar or other substrates for energy production. The new symbiont genome has undergone proliferation of mobile elements resulting in many gene inactivations; nonetheless, it has selectively maintained genes replacing functions of its predecessor for amino-acid biosynthesis. Whereas ancient symbiont partners typically retain perfectly complementary sets of amino-acid biosynthetic pathways, the novel symbiont introduces some redundancy as it retains some pathways also present in the partner symbionts (Sulcia muelleri). Strikingly, the newly acquired Sodalis-like symbiont retains genes underlying efficient routes of energy production, including a complete TCA cycle, potentially relaxing the severe energy limitations of the xylem-feeding hosts. Although evolutionary replacements of ancient symbionts are infrequent, they potentially enable evolutionary and ecological novelty by conferring novel metabolic capabilities to host lineages.  相似文献   
6.
Two new species of the Macropsinae leafhopper subgenus Pediopsoides (Pediopsoides) Matsumura, 1912, Pediopsoides (Pediopsoides) damingshanensis Li, Dai & Li, sp. n. and Pediopsoides (Pediopsoides) tishetshkini Li, Dai & Li sp. n., are described and illustrated from Guangxi Province of southern China. A key to males is provided to distinguish the species of the subgenus along with a map showing the distribution of the new species.  相似文献   
7.
Two genera, Dayus Mahmood, 1967 and Znana Dworakowska, 1994 of the leafhopper tribe Empoascini (Hemiptera: Cicadellidae: Typhlocybinae) are reviewed. One new species of each genus, Dayus furcatus sp. nov. and Znana furca sp. nov., are described from Thailand. A checklist and distribution summary of Dayus Mahmood species is given. Male habitus photos and illustrations of male genitalia of the two new species and notes on allied species are also provided.  相似文献   
8.
研究了中国小绿叶蝉族羿小叶蝉属Helionides,提出了4个新组合,报道了采自中国南方的2新纪录种,提供了中国该属已知种的检索表。  相似文献   
9.
The biodiversity of insects within urban areas has been relatively little studied. Given the large and ever increasing extent of urban areas, and that the insect species richness there can be high, it is important to know the factors determining that aspect of biodiversity. In this study two of these factors, namely habitat management and area, were considered. Arboreal and grassland Hemiptera, and grassland plants, were sampled on 18 roundabouts and other road enclosed sites in the town of Bracknell. Hemiptera were sampled using suction sampling and tree beating. A significant species–area relationship was found for arboreal Hemiptera, which was strongly related to habitat diversity. For both grassland plants and Hemiptera, grassland management, by mowing, had a significant effect on species richness. Despite the management grassland plants showed a significant species–area relationship. However the effect of management on Hemiptera was great enough to outweigh any area effect. As the size of open spaces is often constrained in urban areas, altering habitat management has a greater potential for enhancing biodiversity. For arboreal Hemiptera choice of trees for planting is of particular importance, while for grassland Hemiptera diversity would be increased with a reduction in the intensity of management, such a reduction in the frequency of mowing.

Zusammenfassung

Die Biodiversität der Insekten auf urbanen Flächen ist relativ wenig untersucht. Angesichts der großen und der immer größer werdenden Ausdehnung urbaner Gebiete und angesichts dessen, dass der Artenreichtum der Insekten dort groß sein kann, ist es wichtig die Faktoren zu kennen, die diesen Aspekt der Biodiversität bestimmen. In dieser Untersuchung wurden zwei dieser Faktoren, nämlich Habitatmanagement und Fläche, betrachtet. Baum- und wiesenbewohnende Hemiptera sowie Wiesenpflanzen wurden in 18 Kreisverkehren und anderen straßenumschlossenen Orten innerhalb der Stadt Bracknell gesammelt. Die Hemiptera wurden mit Saugproben und Klopfproben an den Bäumen gesammelt. Für die baumbewohnenden Hemiptera wurde eine signifikante Art-Areal-Beziehung gefunden, die in enger Beziehung zur Habitatdiversität stand. Sowohl für die Wiesenpflanzen als auch für die Hemiptera hatte das Wiesenmanagement in Form von Mahd einen signifikanten Einfluss auf den Artenreichtum. Trotz des Managements zeigten die Wiesenpflanzen eine signifikante Art-Areal-Beziehung. Die Auswirkungen des Managements auf die Hemiptera waren jedoch groß genug, um den Arealeffekt zu überwiegen. Da die Größe offener Flächen in städtischen Gebieten oft beschränkt ist, hat die Änderung des Habitatmanagements ein größeres Potenzial die Biodiversität zu erhöhen. Für baumbewohnende Hemiptera ist die Auswahl der Bäume für die Bepflanzung von besonderer Wichtigkeit, während für die wiesenbewohnenden Hemiptera die Diversität durch eine Verringerung der Managementintensität erhöht würde, wie z. B. durch die Verringerung der Mahdfrequenz.  相似文献   
10.
    
Ling Qu  Ren-Huai Dai 《ZooKeys》2014,(434):47-55
Three new species, Tambocerus dentatus, T. longicaudatus and T. robustispinus spp. n. from southern China, are described and illustrated. A checklist and distribution to the Tambocerus species from China is provided together with a key for their separation.  相似文献   
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