开放新拟钉螺

**开放新拟钉螺**（學名：**'）是[[新拟钉螺属]]的其中一個[[淡水螺]]物種，屬於[[盖螺科]]的[[水生動物|淡水生]][[腹足纲]][[软体动物]]。
過往這個物種是本屬唯一的一個物種；但現時此屬已有至少兩個已描述的物種。

开放新拟钉螺已知是（**'）的唯一中間宿主，可引致。

## 分佈
本物種目前只見於中南半島上流經柬埔寨、老撾及泰國的九條河流流域的31個地點，已知的分佈範圍從柬埔寨湄公河流域的桔井市 南部至老撾中部凯山丰威汉市的。

本物種見於下列地點：
* 湄公河沿岸及東北部公河上游河谷
* 
* 東北部

本物種的位於老撾的Ban Na。

## 形態描述
A detailed account of the anatomy of *Neotricula aperta* was given by Davis et al. in 1976.

Three strains of *Neotricula aperta* have been recognized (called α, β and γ), on the basis of shell size and body pigmentation. Although all three strains are susceptible to **' (γ> > β > α), only the γ-strain is epidemiologically significant.

==生態學==
''Neotricula aperta'' is exclusively [[岩生植物]] or [[epixylic]] (on rotting wood). ''Neotricula aperta'' is found only in shallow areas (typically 0.5 to 3 m deep) of the Mekong river and some of its tributaries. The snails are restricted to areas where the current is moderate (around 2 × 10<sup>3</sup> m<sup>3</sup>s<sup>−1</sup>), the water is clear and the bed rock forms (almost flat) platforms where agal [[aufwuch]]s is extensive. Such conditions exist only during the [[旱季]] in the lower Mekong (March to May) and so ''Neotricula aperta'' populations persist mostly by recruitment (from eggs laid on stones in the previous year) or re-colonization from other rivers, and transmission of **' is seasonal. 人口密度 can reach up to 4734 snails per m².

In addition, *Neotricula aperta* is not known from waters of low 電導率 or pH and is calciphilic; the pH of all *Neotricula aperta* habitats sampled to date is > 7.5 and the river systems in which the snails are found have always been those draining 喀斯特地形 areas. More recently, *Neotricula aperta* has been found in the primary streams emerging from karst springs, close to the origins of the streams. The snail *Neotricula aperta* requires hard water to provide the 钙 needed  for rapid 手性 (腹足綱) growth as populations re-establish in the Mekong river each year following the annual flood.

The ecological requirements of *Neotricula aperta* indicate that this snail will not become established in the reservoirs or downstream channels of dams in the region and that flooding of habitats by impoundment will eliminate all *Neotricula aperta* populations from the affected area.

*Neotricula aperta* grazes the algal epilithon and therefore, unlike species such as *[[Biomphalaria]]* (African vector of other kind of schistosomiasis), cannot survive in areas where sediment is depositing and preventing the growth of the algae upon which it feeds. Indeed, ecological studies of *Neotricula aperta* have shown that this snail is found only on stones covered with fine sediments and that this species is highly sensitive to 淤积.

## 參考文獻

## 延伸閱讀
*Attwood S. W. (1994). "Rates of recruitment among populations of the freshwater snail *Neotricula aperta* (Temcharoen) in North East Thailand". **' **60**(2): 197-200. .
*Attwood S. W. (1995). "The effect of substratum grade on the distribution of the freshwater snail ''y-Neotricula aperta'' (Temcharoen), with notes on the sizes of particles ingested". **' **61**(1): 133-138. .
*Attwood S. W., Upatham E. S. & Southgate V. R. (2001). "The detection of *Schistosoma mekongi* infections in a natural population of *Neotricula aperta* at Khong Island, Laos, and the control of Mekong schistosomiasis". **' **67'''(3): 400-405. .

## 外部連結