开放新拟钉螺

开放新拟钉螺（学名：Neotricula aperta）是新拟钉螺属的其中一个淡水螺物种，属于盖螺科的淡水生腹足纲软体动物。

过往这个物种是本属唯一的一个物种；但现时此属已有至少两个已描述的物种。

开放新拟钉螺已知是湄公血吸虫（Schistosoma mekongi）的唯一中间宿主，可引致湄公血吸虫病。

## 分布

本物种目前只见于中南半岛上流经柬埔寨、老挝及泰国的九条河流流域的31个地点，已知的分布范围从柬埔寨湄公河流域的桔井市 南部至老挝中部凯山丰威汉市的。

本物种见于下列地点：

- 柬埔寨淡水贝列表湄公河沿岸及东北部公河上游河谷
- 老挝淡水贝列表
- 泰国淡水贝列表东北部

本物种的模式产地位于老挝的Ban Na。

## 形态描述

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.

## 生态学

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 × 103 m3s−1), the water is clear and the bed rock forms (almost flat) platforms where agal aufwuchs 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 电导率 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 (腹足纲) 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.

## 延伸阅读

- Attwood S. W. (1994). "Rates of recruitment among populations of the freshwater snail Neotricula aperta (Temcharoen) in North East Thailand". 60(2): 197-200. 10.1093/mollus/60.2.197.
- 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. 10.1093/mollus/61.1.133.
- 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. 10.1093/mollus/67.3.400.

## 基本资料

- 说明：隶属新拟钉螺属的开放新拟钉螺的贝壳特写
- 说明：Neotricula aperta on a stone
- 学名：Neotricula aperta
- 命名者：(Temcharoen, 1971)
- 异名：Lithoglyphopsis aperta、Neotricula apart（拼写错误）、Tricula aperta