Global diversity of black flies (Diptera: Simuliidae) in freshwater

Black flies are a worldwide family of nematocerous Diptera whose immature stages are confined to running waters. They are key organisms in both aquatic and terrestrial ecosystems, but are perhaps best known for the bloodsucking habits of adult females. Attacks by black flies are responsible for reduced tourism, deaths in wild and domestic birds and mammals, and transmission of parasitic diseases to hosts, including humans. About 2,000 nominal species are currently recognized; however, certain geographical regions remain inadequately surveyed. Furthermore, studies of the giant polytene chromosomes of larvae reveal that many morphologically recognized species actually consist of two or more structurally indistinguishable (yet reproductively isolated) sibling species. Calculations derived from the best-known regional fauna—the Nearctic Region—reveal that the actual number of World black fly species exceeds 3,000. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. Guest editors: E.V. Balian, C. Lévêque, H. Segers & K. Martens Freshwater Animal Diversity Assessment     

中国蚋属一新种：双翅目：蚋科

本文报道中国蚋属一新种,重庆蚋Ｓｉｍｕｌｉｕｍ（Ｓｉｍｕｌｉｕｍ）ｃｈｏｎｇａｉｎｇｅｎｓｅ ｓｐ．ｎｏｖ。标本采自重庆四面山,模式标本保存重庆市卫生防疫站。     

真蚋亚属一新种（双翅目：蚋科）

本文报道蚋属（Ｓｉｍｕｌｉｕｍ）真蚋亚属（Ｅｕｓｉｍｕｌｉｕｍ）一新种──四面山真蚋Ｓ．（Ｅ）ｓｉｍｉａｎｓｈａｎｅｎｓｉｓｓｐｎｏｖ．。模式标本采自重庆四面山,保存于重庆市卫生防疫站。     

Quantitative aspects of sperm transfer in Simulium decorum (Diptera: Simuliidae)

The mean number of sperm ejaculated into the spermatophore by the male black fly, Simulium decorum Walker, was 4048, as determined from 43 counts. The completeness and rate of sperm transfer were estimated by counts from the spermatophore and female spermatheca at selected times after copulation ended. The beginning of transfer occurred at the earliest about 4 min after copulation, but could be delayed until 30 min. Transfer rate was interpreted as constant at about 73 sperm/min and was usually completed by about 55 min after copulation. All spermatozoa appeared to be moved to the single spermatheca.     

A SURVEY OF BLACKFLIES WITH THREE NEW SPECIES FROM KUANKUOSHUI, GUIZHOU, CHINA (DIPTERA, SIMULIIDAE)

首次记载贵州省宽阔水自然保护区蚋科Simulüdac 14种,并记述其中3新种,包括遵义蚋Simulium(Simulium)zwunyiense sp.nov.和新尖板蚋Simuium(Simulium)neoacontum sp.nov.以及隶属于山蚋亚属Simulium(Montisimulium)的离板山蚋Simulium(Montisimulium separatum sp.nov..模式标本存放于贵阳医学院生物学教研室.遵义蚋,新种S.(S) zunyiense sp.nov.(图1～13)隶属于蚋亚属杂色蚋组variegatum group,与本组已知近缘种主要区别在雄尾结构,如生殖肢端节,生殖腹板和中骨的形状特殊.正模♂,贵州遵义市宽阔水自然保护区( 28°12′N,107°18′E;海拔l 483 m),2010-09-20,修江帆,陈黔采.词源:新种种名源自模式产地.新尖板蚋,新种S.(S.) neoacontum sp.nov.(图14 ～19)隶属于蚋亚属淡足蚋组malyschevi group,与尖板蚋S.(S.) acontum Clen et al.,近似,但雄虫生殖肢端节,生殖腹板和中骨的形状迥异,此外,其呼吸丝排列方式也有明显差异.正模♂,贵州宽阔水自然保护区让水( 28°17＇N,107°08′E;海拔682 m),2010 08-13,修江帆采.词源:新种种名源自其形态极似尖板蚋S.(S.) acontum,冠以“neo”以示区别.离板山蚋,新种S.(Montisimulium)separatum sp.nov.(图20 ～28)隶属于山蚋亚属Subgenus M.ontinulium与绒丝山蚋S.(M.)nemoriragum(Datta,1973)近似,主要区别是雌虫生殖板内缘远离,蛹呼吸丝背对具短茎.此外,幼虫头扇毛和肛鳃次生叶数目也有明显差异.正模♀,贵州宽阔水自然保护区大洞( 28°12＇N,107°18＇E;海拔1 483 m),2010-08-20,修江帆,陈黔采.词源:新种种名源自其雌虫生殖板内缘分离.     

湖北神农架自然保护区一新特蚋种(双翅目,蚋科)(英文)

描记采自湖北神农架自然保护区一蚋属蚋亚属新种,齿端蚋Simulium(Simulium)dentastylum sp.nov..模式标本存于贵阳医学院生物学教研室.     

桐柏山维蚋一新种(双翅目,蚋科)

记述湖北省桐柏山维蚋1新种.模式标本存放于贵阳医学院生物学教研室.桐柏山维蚋,新种Simulium(Wilhelmia)tongbaishanense sp.nov.(图1～16)根据蛹的形状,新种似与高桥维蚋、兴义维蚋和北京维蚋近缘.但可根据成虫足的颜色、雌虫外生殖器的形状、蛹的头和前胸疣突缺如、幼虫后颊裂形状等综合特征与上述近缘种相区别.正模♀,副模1♀,2♂♂,11蛹及2幼虫,2004-08-10,幼虫和蛹采自湖北桐柏山急流中水草.     

Dipteran predators of Simuliid blackflies: a worldwide review

Haematophagous female blackflies (Diptera: Simuliidae) are serious biting pests and obligate vectors of vertebrate pathogens, namely filarial Dirofilaria, Mansonella, Onchocerca and protozoal Leucocytozoon. Immature stages of Simuliidae inhabit lotic waterways, the sessile larvae filter-feeding and often forming a large proportion of the benthic biomass, usually aggregated in well-oxygenated sections of streams, rivers, waterfalls and spillways. Simuliid control practices depend on larvicidal chemicals, biological products (bacteria, nematodes) and environmental modification. The potential use of predators for biological control of Simuliidae has not been exploited. Predators of Simuliidae include examples of at least 12 families of Diptera and other predaceous arthropods (Crustacea and insects: Coleoptera, Odonata, Plecoptera, Trichoptera), invertebrates (notably Turbellaria), as well as browsing fish. Diptera impacting upon simuliid populations comprise mainly Chironomidae, Empididae and Muscidae, although several other families (Asilidae, Dolichopodidae, Phoridae, Drosophilidae, Scathophagidae) play a significant role as predators. Details of predator and prey species and life stages are presented, by zoogeographical region, including the prevalence of cannibalism among Simuliidae.     

Local modification of benthic flow environments by suspension-feeding stream insects

Larval black flies often exhibit spatially aggregated distributions, and individuals within patches can potentially reduce the supply of suspended food particles to downstream neighbors by modifying local flow characteristics. We used hot-film anemometry to quantify the magnitude and spatial extent of flow modifications downstream from feeding Simulium vittatum larvae in a laboratory flume, and to determine whether temporal patterns of flow variation are related to movements of the larval feeding appendages. Mean velocity 1 mm downstream from feeding larvae was reduced by 75%, and the percent reduction in velocity diminished asymptotically with downstream distance. Reduced velocities were evident as much as 60 mm downstream from, and 3 mm to either side of, larvae. Turbulence intensity (i.e., the SD of the velocity time series) was generally higher in this region relative to control flow conditions. Three results demonstrate the major contribution of the larval feeding appendages (i.e., labral fans) to such flow modification. First, there was a minimal reduction in mean velocity 5 mm downstream from non-feeding larvae (i.e., with closed labral fans), whereas mean velocity at the same location was reduced markedly when larvae were feeding. Second, the power spectrum of the velocity time series exhibited greatest power at frequencies that corresponded to the frequency of labral fan motions. Third, fan flick times accounted for most of the variance in the velocity power spectrum. The large local flow modifications that we documented have potentially important consequences for the feeding performance and growth of individuals located within larval aggregations, and are likely to influence behavioral interactions and spacing patterns.