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91.
Oreopithecus bambolii is a Late Miocene hominoid with an extensive fossil record in the Baccinello Basin (Tuscany, Italy), and was the only western European hominoid to survive a major extinction event ca. 9.6 Ma (millions of years ago). Oreopithecus lived in the insular Tusco-Sardinian paleobioprovince, where it evolved many unique anatomical specializations that make it important for understanding the mechanisms and history of Late Miocene hominoid evolution. The eventual extinction of Oreopithecus and its associated fauna ca. 6.5 Ma has generally been attributed to interaction with species that arrived from continental Europe following tectonic collision of the Tusco-Sardinian province with mainland Italy, but palynological, paleontological, and sedimentological records indicate an environmental shift toward more variable climate across the extinction event.To explore the possibility of environmental change as a contributing factor in the extinction of Oreopithecus, we developed a stable carbon and oxygen isotope record from organic matter in paleosols from the Baccinello Basin. These data show very low temporal and spatial variability (indicating plant ecosystem stability through time and space) and provide no evidence for ecologically significant changes in floral composition spanning the extinction event, suggesting that environmental change was not an underlying cause for the extinction of Oreopithecus and its associated fauna. The carbon isotope values fall entirely within the range of isotopic variability for modern plants following the C3 photosynthetic pathway (trees, shrubs, cool-season grasses), indicating that C4 vegetation (warm-season grasses) was not an important component of biomass. When corrected for temporal variation in the carbon isotopic composition of atmospheric carbon dioxide, the paleosol carbon isotope values are consistent with predicted values based on modern plants and the Baccinello palynoflora, supporting the reliability of paleosol isotopic records as paleoecological proxies.  相似文献   
92.
Houghton DC 《ZooKeys》2012,(189):1-389
The caddisfly fauna of Minnesota contains at least 277 species within 21 families and 75 genera. These species are based on examination of 312,884 specimens from 2,166 collections of 937 Minnesota aquatic habitats from 1890 to 2007. Included in these totals is my own quantitative sampling of 4 representative habitat types: small streams, medium rivers, large rivers, and lakes, from each of the 58 major Minnesota watersheds from June through September during 1999-2001. All species are illustrated herein, and their known Minnesota abundances, distributions, adult flight periodicities, and habitat affinities presented. Four species: Lepidostoma griseum (Lepidostomatidae), Psilotreta indecisa (Odontoceridae), and Phryganea sayi and Ptilostomis angustipennis (Phryganeidae) are added to the known fauna. An additional 31 dubious species records are removed for various reasons. Of the 5 determined caddisfly regions of the state, species richness per watershed was highest in the Lake Superior and Northern Regions, intermediate in the Southeastern, and lowest in the Northwestern and Southern. Of the 48 individual collections that yielded >40 species, all but 1 were from the Northern Region. Many species, especially within the families Limnephilidae and Phryganeidae, have appeared to decrease in distribution and abundance during the past 75 years, particularly those once common within the Northwestern and Southern Regions. Many species now appear regionally extirpated, and a few have disappeared from the entire state. The loss of species in the Northwestern and Southern Regions, and probably elsewhere, is almost certainly related to the conversion of many habitats to large-scale agriculture during the mid-20th century.  相似文献   
93.
A survey was conducted to evaluate the number of tree-hole breeding mosquito species and their distribution in the six principal woodland types in Israel. Out of approximately 3,000 mature trees examined, only 38 contained holes that retained water for extended periods of time, and breeding mosquitoes were observed in 27 of them. Two specialized tree-hole breeders, Aedes pulchritarsis Rondani and Aedes geniculatus Oliver, were found breeding at several sites in northern Israel, always at locations 500 m above sea level (a.s.l) and with high annual precipitation. Aedes albopictus Skuse which, in Israel, is known as an opportunistic container breeder, was found in this study to have adapted remarkably well to breeding in tree holes and was found in most forest types investigated and in most tree species which had adequate tree holes. Two other species, Culiseta annulata Schrank and Culex pipiens Linnaeus instars, were found in one of the tree holes, but did not survive to reach maturity.  相似文献   
94.
A Oliva 《ZooKeys》2012,(203):1-14
A new species of the forensically interesting genus Oxelytrum Gistel (Coleoptera, Silphidae), Oxelytrum selknan, is described from Santa Cruz and Tierra del Fuego provinces, Argentina. The new species resembles Oxelytrum biguttatum (Philippi) in outer aspect, but has different male genitalia, in particular a median lobe longer than the paramera. All the described species of Oxelytrum have the median lobe shorter than the paramera. The internal sac, as far as it could be reconstructed from dry-pinned specimens, also shows differences between the two species. A key to the species of Oxelytrum is given and illustrated.  相似文献   
95.
Jang-Liaw NH  Gong YH  Chen IS 《ZooKeys》2012,(199):13-21
A new species of Clariger Jordan & Snyder, 1901 was collected from northern Taiwan. The genus was previously known only from Japanese waters. This discovery is the first formal and southernmost record of these marine gobies from the waters of subtropical Taiwan. The new species, Clariger taiwanensissp. n., is distinguished from its congeners by a unique combination of features: (1) fin rays: dorsal-fin rays III, I/8; anal-fin rays modally I/8; and pectoral-fin rays modally 19 (2+16+1); (2) longitudinal dermal ridge on head with 6 barbels; and (3) specific coloration pattern: head and trunk dark brown with scattered pale spots and blotches; cheek, ventral portion of head sometimes pale with deep brown spots; pectoral-fin base with a dark brown band; and caudal fin mostly dark brown proximally and with alternating and irregular dark brown and pale bands distally. A diagnostic key to all nominal species from Japan and Taiwan is provided.  相似文献   
96.
D Wei  J Liang  D Ren 《ZooKeys》2012,(217):53-61
A new species attributed to the genus Parvifuzia Guo & Ren, 2011, Parvifuzia peregrinasp. n., is described from the Middle Jurassic Jiulongshan Formation of Daohugou Village, Inner Mongolia, China. This new species, with apex of wing almost reaching the end of the abdomen and forewing venation with 30-32 veins at margin, broadens the diversity of Parvifuzia. This new species, with strongly curved cerci, could tightly clasp female and complete copulation more efficiently, same as other members of the family Fuziidae.  相似文献   
97.
秦岭西部山地次生林和人工林大型土壤动物群落结构特征   总被引:3,自引:0,他引:3  
人类对次生林生态系统的长期扰动必然会对地下生态过程产生深刻影响,而土壤动物群落结构和功能多样性对地下生态过程的演变有重要的指示意义.本文以小陇山林区恢复近30年的次生林和栽植近30年的油松、日本落叶松、欧洲云杉和粗枝云杉林为对象,通过对5种林型土壤动物群落密度调查,采用PCA排序和方差分析等方法,探讨了不同林型土壤动物群落结构特征和营养结构.结果表明:油松林和日本落叶松林土壤动物群落密度是次生林的3.0和2.1倍;油松和日本落叶松人工林土壤动物群落中消费者/分解者比值明显高于次生林,油松林和日本落叶松林消费者/分解者的比值显著高于欧洲云杉林和粗枝云杉林;不同人工林土壤动物群落结构存在明显差异,油松林和日本落叶松林土壤动物群落密度是粗枝云杉林的4.5和3.1倍,而油松林土壤动物群落类群丰富度是欧洲云杉林和粗枝云杉林的1.5倍.  相似文献   
98.
据作者调查和文献报道,本文列出了江西产90种园蛛在江西、中国和全球的地理分布;在世界动物地理区划水平上,江西园蛛主要由东洋界以及东洋界和古北界成分组成;在中国动物地理区划水平上,江西园蛛主要由华中区,华中区+华南区+西南区以及华中区+西南区跨界成分组成;与国内23省(区)区系组成比较,江西园蛛与湖南的共有种最多,与西藏共有种最少;文章最后分析了江西园蛛物种结构的特点.  相似文献   
99.
The Formosan subterranean termite, Coptotermes formosanus, with its huge colonies, is a major urban pest in several southern states and Hawaii as well as in South Asia. Because of their cryptic nature (underground habitat) and very long life cycle, not much is known about molting in termite workers. In C. formosanus, the workers stop foraging and lose their gut fauna, respectively, approximately 10 and 5 days prior to ecdysis. In any given colony an average of 1.01% (range 0.6-1.8) of the workers were found to molt each day under laboratory conditions. Workers destined to molt become sluggish and their head capsules develop a mottled texture one day prior to ecdysis. Ecdysis was generally accomplished with the assistance of other workers, which also fed on the exuviae. Immediately after molting worker mandibles were light pink in color and became fully melanized approximately two days later. Gut fauna were acquired on the fourth day after molting. Flagellates were transferred as small encysted cells from other workers through proctodeal feeding. Juvenile hormone III titer ranged between 30-41 pg/mg bodyweight in all stages except in workers sampled 6 days prior to ecdysis. In these workers the titer was 80.5 pg/mg. The high juvenile hormones (JH) titer may also be involved in causing defaunation. Ecdysteroid titer increased from 2.1 pg/mg in non-molting workers to 359.5 and 332.4 pg/mg one and two days following defaunation, respectively. There was a second smaller peak two days prior to ecdysis.  相似文献   
100.
Taxonomic relationships between Rhabdorrhynchus and Pachycerus are discussed, and two new species of Rhabdorrhynchus are described: Rhabdorrhynchus sauditus (type locality: Saudi Arabia, As Shāqqah al Yamānīyah, 19°42'N, 40°48'E) and Rhabdorrhynchus emir (type locality: United Arab Emirates, Jebel Ali, 24°59'N, 55°43'E). Some hypotheses on the distribution of the new species in the Arabian Peninsula, based on a biogeographical analysis, are proposed.  © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society , 2008, 152 , 25–37.  相似文献   
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