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211.
212.
Two sulfate-reducing bacteria (SRB) were isolated from a mixed culture enriched with benzoate obtained from gut homogenate of the soil-feeding higher termite, Cubitermes speciosus. The organisms were vibrioid rods, staining Gram-negative, which performed incomplete substrate oxidation. They differed in several features. The smaller one, strain STp, was motile with a single polar flagellum. This strain differed from Desulfovibrio desulfuricans only by its inability to oxidize malate and pentanol. The bigger one, strain STg, differed from Desulfovibrio giganteus only by its nonmotility and a lower length. It is the first evidence of the presence of SRB in termite gut. 相似文献
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三明地区林木白蚁种类、分布及危害的调查 总被引:4,自引:0,他引:4
在三明全区范围内设点普查,得知共有林木白蚁2科9属22种,其中中华葫白蚁、海南大白蚁、普见家白蚁、大头家白蚁、高山散白蚁为福建省首次发现危害林木。黄翅大白蚁、闽华歪白蚁、大近歪白蚁、歪白蚁、中华葫白蚁、小象白蚁、海南大白蚁、普见家白蚁、大头象白蚁、蛋头蔡白蚁、黄肢散白蚁、高额散白蚁、高山散白仪、细颏散白蚁、武宫散白蚁、尖唇异白蚁为本地区首次发现危害林木。三明地区白蚁优势种有黑翅土白蚁、黄翅大白蚁和家白蚁。黑翅土白蚁等白蚁对林木造成严重危害,已成为当前林业生产中的一大难题。三明地区林木白蚁区系分布有以下特点:1)林木白蚁种类多,分布广泛,危害较为普遍;2)土白蚁、大白蚁是危害林木的主要类别;3)全区范围白蚁发生情况是由北向南蚁种延增,危害趋重。 相似文献
215.
Ecosystem engineers are organisms that influence their environment, which includes alterations leading to habitat provisioning for other species. Perhaps the most well‐examined guild of species provisioning habitat for other species is tree cavity excavators or woodpeckers (Picidae). Many studies have examined the suite of secondary cavity users that rely on woodpeckers, and how the ecological network of secondary users, collectively referred to as the nest web, changes across communities. Despite similar habitat provisioning processes, fewer studies have assessed the suite of species associated with burrowers providing access to subterranean habitat. Here, we begin to characterize the burrow web provisioned by American badgers (Taxidea taxus) and evaluate the diversity and frequency of species interactions we detected at abandoned badger burrows in Wyoming, USA. We deployed camera traps at 23 badger burrows and identified interactions with the burrow by birds, mammals, and reptiles. Overall, we discovered 31 other species utilizing badger burrows, consisting of 12 mammals, 18 birds, and 1 reptile. Mammals, other than American badgers themselves and other fossorial species such as ground squirrels (Urocitellus sp.), frequently using burrows included mice (Peromyscus sp.), long‐tailed weasel (Mustela frenata), pygmy rabbit (Brachylagus idahoensis), and desert cottontail (Sylvilagus audubonii). Of the 18 bird species detected, most accounted for <5% of overall detections, besides chipping sparrows (Spizella passerina) at 7.2%–11.5% of detections. The most common category of detection by bird species was foraging, contrary to mammals, which used the burrow frequently and were commonly observed entering and exiting the burrow. This work provides additional context on the ecological role of American badgers within their environment. More broadly, this work scratches the surface of many remaining questions to explore with the aim of advancing our understandings about burrow webs across the diversity of burrowing species and the communities in which they occur. 相似文献
216.
Heterotermes tenuis is a native termite of large negative impact on the Brazilian economy. Many studies have focused on optimizing the baiting method for termite control by improving its use and its efficacy. In order to maximize termite bait consumption, this study aimed to select nutrient solutions which are able to enhance termite feeding. The effects of some sugars and urea on feeding preference of the subterranean termite H. tenuis were determined by double choice feeding tests, and the consumption was evaluated by variation in dry mass of filter paper after 28 days of termite feeding. Most of the solutions tested did not significantly influence feeding of H. tenuis . Termites fed preferentially on filter paper treated with 0.03 g/ml trehalose and 0.015 g/ml urea solutions. The data indicate that trehalose and urea solutions are phagostimulants to H. tenuis , and their future use in bait matrices may increase consumption of baits and improve this control technique. 相似文献
217.
C. R. Jackson N. R. Lubbe M. P. Robertson T. H. Setsaas J. van der Waals & N. C. Bennett 《Journal of Zoology》2008,274(1):13-17
The endangered Juliana's golden mole Neamblysomus julianae occurs in three small, geographically isolated populations within South Africa. As a sand-swimmer, it is a habitat specialist and has a highly fragmented distribution within each population. There is a need for a conservation action plan for this species, but this is difficult because of the dearth of knowledge of its biology, including its habitat characteristics. To better understand its patchy distribution, we selected 48 plots that were occupied or unoccupied by golden moles and measured the soil properties in each plot. The size distribution of sand particles influenced the density and compactability of the soil, and both were positively correlated with the presence of golden moles. These soil characteristics are thus vital in understanding and describing the distribution of this cryptic species. 相似文献
218.
219.
Resolving the phylogenetic history of a 'true' worker caste in termites is essential to our understanding of termite eusocial evolution. Whether this caste is ancient and monophyletic or derived and polyphyletic will have a tremendous impact on our interpretation of termite eusocial history and remains an outstanding question in termite biology. Recent work has begun to re-examine this question in light of new phylogenetic information, but new questions have now arisen about how best to model character state changes in termite caste systems. In the present paper, we compare the models of Grandcolas and D'Haese [J. Evol. Biol. 15 (2002) 885] and Thompson et al. [J. Evol Biol. 13 (2000) 8691 and attempt to make explicit how these proposals differ with respect to the number of, and homology between, character states. We highlight the support each model has for the two principal, but competing, evolutionary hypotheses outlined above. 相似文献
220.
Ye W Lee CY Scheffrahn RH Aleong JM Su NY Bennett GW Scharf ME 《Molecular phylogenetics and evolution》2004,30(3):815-822
DNA sequence comparisons of the mitochondrial COII, 16S, and 12S rRNA genes were used to infer phylogenetic relationships among the six known US Reticulitermes species (Reticulitermes flavipes, Reticulitermes arenincola, Reticulitermes tibialis, Reticulitermes hageni, Reticulitermes virginicus, and Reticulitermes hesperus) and the closely related European species Reticulitermes santonensis. The interspecific pairwise sequence divergence, based on uncorrected "p" distance, varied up to 10% across the COII, 4.9% across the 16S, and 3% across the 12S fragments. Phylogenetic trees were constructed using maximum parsimony, likelihood, and distance methods. The combined results suggest several phylogenetic relationships including: (i) R. flavipes, R. arenincola, and European R. santonensis are possibly conspecific; (ii) R. virginicus and R. hageni are closely related species; and (iii) R. tibialis and R. hesperus are closely related species. Interestingly, while there is apparent synonymity between R. flavipes and R. arenincola by DNA sequence, there are clear morphological differences in the soldier caste. This finding suggests a combination of molecular and morphological approaches are necessary for accurate species identification. These data lend resolution to the complex problem of Reticulitermes systematics, and will assist future efforts directed toward characterizing species distribution and ecology. 相似文献