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''Stenacron'' is a genus of mayflies in the family Heptageniidae. ==References== * ---- The genus of Stenacron (Jensen 1974) is a vastly understudied and largely misunderstood genus. From P A Lewis (1974) "The taxonomy and Ecology of Stenonema Mayflies" forward, very little to nothing has been done with this genus in the field and in laboratories. I suspect in part that is because some of the forms are known for living in Toxic and or organic waste. The other is the very complex taxonomic confusion that exist with the synonym forms. However I suspect a revision may be in the future. According to Dr Jeffery Webb DNA has shown some revisions are necessary and likely to happen in the future. ---- Stenacron ecology Although the larva can be found in many different conditions they have some basic and preferred requirements. All samples I have collected regardless of the form or species are found near the bank. They tend to cling to the underside of rocks that are a minimum of 8 X 8 inch's and 2 inch's thick. The larger the rock the greater the population per rock. They are seldom found in the faster riffle waters but more so at the slower moving banks. Typically with a water depth of no less that 3 inch's and up to 16 inch's deep. The most important factor is the waters "DO" (dissolved oxygen). Stenacron can live in waters that are not moving and low in (DO). In rearing experiments I have found that they can survive and hatch in a bucket with little oxygen added for up to 4 day's. However in a watershed they do prefer a stable and moderate DO in which greater populations will occur. Lewis (1974) showed that the form (Stenacron interpunctatum / heterotarsale) historically carried a EBI (Empirical Biotic Index) rating of a level (7) showing a high tolerance level to pollution's both Toxic and Organic. (under updates) ---- Brief history Dr J R Traver the second author of the "Biology of a Mayfly" (1935) erected (3) distinct groups in the genus Stenonema in (1933). The interpunctatum group later became the genus Stenacron. Steven L Jensen in (1974) erected the genus name Stenacron. There are currently (16) forms that reside in this genus and only (7) of the forms carry a valid species status. The other remaining forms have all been synonymized into the valid species (Stenacron interpunctatum). These forms are referred to as (Stenacron interpunctatum / interpunctatum) not as (Stenacron interpunctatum)(Say 1839). Thomas Say the god father of American Entomology first documented the species (interpunctatum) in (1839) in Indiana from; (20) halotypes and (14) paratypes. Hagan (1861) confirms and expands the geographical range of the species with the collection of others in Virginia that concurred with Says (1839) halotypes. ---- Here is a list of the currently valid species as of (2014); (Stenacron candidum), (Stenacron carolina), (Stenacron floridense), (Stenacron gildersleevei), (Stenacron interpunctatum) (Say 1839), (Stenacron minnetonka), (Stenacron pallidum), ---- The list below are the synonym forms that make up the interpunctatum complex. (Stenacron interpunctatum / affine), (Stenacron interpunctatum / areion), (Stenacron interpunctatum / canadense), (Stenacron interpunctatum / conjunctum), (Stenacron interpunctatum / frontale), (Stenacron interpunctatum / heterotarsale), (Stenacron interpunctatum / majus), (Stenacron interpunctatum / ohioense), (Stenacron interpunctatum / proximum) ---- 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Stenacron」の詳細全文を読む スポンサード リンク
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