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1.
Presently the only keys available for identification of genera of Anthonomini are limited to those of the United States of America and Canada. A dichotomous key is presented to identify all genera of Mexican and Central American Anthonomini. Previous keys do not include the genera Achia, Botanebius, Loncophorus, Loncophorellus and Melexerus. A brief synopsis is given for each genus and photographs of representative species are included.  相似文献   
2.
作为种子捕食者和种子扩散者, 啮齿动物对产坚果植物的自然更新有很大作用。然而, 对啮齿动物鉴别虫蛀种子的能力颇有争议。2001 年秋季在中国四川都江堰市实验林场, 以3 种比例(I1∶S = 1∶1 , I1∶S = 4∶1 和I1∶I2∶S = 1∶1∶1)供给啮齿动物4 种壳斗科种子: 栓皮栎( Quercus variabilis) 、枹树( Q. serrata) 、青冈( Cyclobalanopsis glauca) 和栲树( Castanopsis fargesii) 的3 种坚果型(即饱满种子(S) , 不含象虫的虫蛀种子(I1) 和含象虫的虫蛀种子( I2 ) 验证了啮齿动物能够准确地鉴别虫蛀种子这一假说。结果表明, 在3 种比例下4 种坚果的虫蛀种子的消失速率均慢于饱满种子。即使虫蛀种子的比例增加, 啮齿动物显著地搬走了更多的饱满种子(67%~92%) 。当虫蛀种子的比例增加时, 虫蛀种子就地消耗和拒绝的比例降低, 搬走比例增加。啮齿动物并不拒绝虫蛀种子, 这可能与它们的可利用性(如象虫可以作为蛋白质的补充) 和数量以及它们的觅食行为有关。结果证实啮齿动物能准确地鉴别虫蛀种子, 从而有区别地搬走并贮藏更多的饱满种子, 消耗一部分可以利用的虫蛀种子(包括其内的象虫) 。这样, 啮齿动物通过对饱满种子和虫蛀种子的鉴别和选择会影响不同种子的命运, 从而对这些坚果植物的自然更新产生影响。  相似文献   
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4.
Weevil (Curculionidae, Coleoptera) species richness and composition were investigated and compared among larch [Larix kaempferi (Lamb.) Carriére] plantations, secondary forests, and old-growth forests in the central mountainous region of Japan. In addition, to assess the effects of forest-management practices, namely thinning and long-rotation logging schedules (long rotation), the weevil assemblages of recently thinned middle-aged and long-rotated larch plantations were compared with those of middle-aged larch plantations. Malaise traps were set in 44 stands of these forest types, and weevils were separated and identified. Several environmental factors other than forest type were also examined. Weevil species richness and diversity indices [Shannon-Wiener diversity index (H) and Simpsons index of diversity (D)] were higher in the secondary forest than in the larch plantation. Because of its wide distribution and higher weevil species richness, the secondary forest contributed to maintaining weevil diversity in this region. Old-growth forest had higher diversity indices (H and D) than did the larch plantation. The secondary forest had the highest number of species in total. Though the number of individuals was the highest in larch plantation, species richness, H and D of the plantation were generally low. Weevil community structure and species composition differed among the three forest types, but the difference in weevil composition between the larch plantation and the other two forest types was the largest. Forest type is probably the most important factor for determining the differences in weevil assemblage, and further, both dominant tree type (coniferous trees versus broad-leaved trees) and the number of mature tree species seem to be important factors for weevil species composition. Among forest management practices, long rotation caused diversity indices (H and D) to increase while thinning appeared to cause only minor changes in the weevil assemblages. Because species richness and species composition of Curculionidae well reflected the differences in forest types and some other environmental factors investigated, this family seems suitable for diversity research in forests. Further research on biodiversity with the use of this family should, therefore, be expected.  相似文献   
5.
A new genus Moreiba is described for Strophosoma canariense Franz, 1995 (type species) and placed in Laparocerini. It differs from Laparocerus Schoenherr, 1834 by the small size, the strongly transverse rostrum, the dense longitudinal strigosity on head and rostrum, the body covered by dense, adpressed scales and short, semierect subspatulate to parallel setae, the slender antennae with bisinuate scape and short oval club, the granulate pronotum and all tibiae lacking a mucro in both sexes. Moreiba canariensis (Franz, 1995), comb. n., is the only described species, distributed in El Hierro and Gran Canaria. The tribal placement of the genera Aphyonotus Faust, 1895, Asmaratrox Heller, 1909, Straticus Pascoe, 1886 and Cyrtozemia Pascoe, 1872 is discussed.  相似文献   
6.
Perapion connexum (Schilsky) is recorded for the first time from Hungary and Kyrgyzstan, and new distribution data from Ukraine and Russia are provided. Preliminary placements of this weevil in faunal checklists for Poland and Slovakia are here documented with detailed data. Its occurrence in Austria based on older evidence, is discussed. The neophytic and invasive in Central Europe sorrel Rumex confertus Willd. is confirmed to be its unique host plant in Poland. Morphology of the newcoming weevil is described and illustrated, and the key to all Central European species of Perapion is presented.  相似文献   
7.
Thermogenically elevated cone temperatures were measured in two Macrozamia cycad species that differ in their daily heating time. Mathematical models of the cones‘ thermo-physics were tested for their accuracy in predicting these cone temperatures and for comparison of the energetics of both species and the sexes within species. These models accurately predicted temperatures over ~8-h periods with average errors of: 0.46°C for Macrozamia lucida, pollinated by the thrips, Cycadothrips chadwicki, that moves during mid-day concurrent with cone heating; and 0.38°C for Macrozamia machinii, pollinated by the weevil, Tranes sp., that moves after sunset during cone heating. The combination of models and experiments revealed a thermogenic sexual dimorphism in both species. For M. lucida, the estimated female mass specific metabolisms, and their theoretically possible and actual temperature increases due to thermogenic metabolism were only 57, 67, and 76% of males. In addition, female thermogenic metabolisms began and peaked much earlier and lasted significantly longer than males (all differences >1 h), and female metabolic peaks preceded their temperature peaks by 65 vs. 46 min for males. The timing of almost all male cone metabolic peaks was optimized with respect to the diurnal ambient heating cycle so that cone temperatures achieved a maximum temperature gain, whereas most female metabolic peaks occurred much earlier than optimal. In M. machinii, thermogenic sexual dimorphism is much larger since its male peak metabolisms are larger, and its females’ peaks are much smaller compared to those of M. lucida. This study provides new information regarding the energetics of cycad cones that is relevant to understanding the interactions of the plant traits with their obligate pollinators’ behavior.  相似文献   
8.
There are long‐standing controversies on the taxonomic status of Ectemnorhinus weevil species occurring on the sub‐Antarctic Prince Edward Islands. Since the two islands that constitute the Prince Edward Islands archipelago (PEIA), Marion Island (MI) and Prince Edward Island (PEI), differ in terms of alien invasive species such as the introduced house mouse Mus musculus and conservation management strategies, it is important to consider inter‐island dynamics when investigating inter‐specific relationships. Using a combined molecular phylogenetic and morphometric approach, we attempted to resolve the taxonomic status of the PEIA Ectemnorhinus weevil species. A COI gene phylogeny was inferred following the genetic characterization of 52 Ectemnorhinus weevils from both islands, and morphometric assessment using a set of 15 linear, external measurements was used to differentiate between the two currently recognized species, Ectemnorhinus similis and Ectemnorhinus marioni. Analyses revealed the presence of two genetically and morphometrically distinct species on PEI, whilst evidence for a single species, comprising diverse genetically discrete populations was found on MI. Based on these results, the species unique to PEI has been designated Ectemnorhinus kuscheli n. sp. whilst we confirm the synonymy between E. similis and E. marioni, the two species originally described from MI. E. kuscheli appears to be restricted to PEI, whereas E. similis occurs on both MI and PEI.  相似文献   
9.
Pseudaspidapion botanicumsp. n. from China is described and figured. Its host plant is Grewia biloba G. Don var. parviflora (Bunge) Hand.-Mazz (Malvaceae: Grewioideae). The genus Harpapion Voss, 1966 is recorded as new for China and Vietnam and two comb. n. are proposed: Harpapion vietnamense (Korotyaev, 1985) (from Aspidapion) and Harpapion coelebs (Korotyaev, 1987) (from Pseudaspidapion). A key to the known species of the genus Pseudaspidapion from China is presented.  相似文献   
10.
Further evidence for a specialized plant-pollinator relationship in the weevil pollinatedCarludovicoideae (Cyclanthaceae) is presented, with emphasis on the previously uninvestigated genusSphaeradenia. Weevils use the carludovicoid inflorescence for feeding, shelter, mating, and oviposition, the last-mentioned activity in the usually caducous staminate flowers. While visiting the inflorescence, they effect pollination. Adaptations, advantages, and consequences for this sophisticated system, both of the plants and pollinators, are discussed.  相似文献   
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