瘤蜷

content: "Tarebia granifera" also occurs in several estuaries along the KwaZulu-Natal coast. Prominent among these is the dense population (±6038 m) found at a 盐度 of 9.98‰ (28.5% sea water) in Catalina Bay, Lake St Lucia, 伊西曼格利索湿地公园, KwaZulu-Natal. These records show that "Tarebia granifera" is able to colonize 汽水 (水域) and moderately saline habitats and reach high densities there. From observations in 波多黎各 it was suggested that snails could survive temporarily saline conditions for several weeks by burying themselves in the substratum, emerging when fresh water returned.  In common with other Thiaridae, "Tarebia granifera" is primarily a 海底生物界 species and in South Africa has been collected on a variety of substrata in both natural and artificial waterbodies, e.g. sand, mud, rock, concrete bridge foundations and the concrete walls and bottoms of reservoirs, irrigation canals and ornamental ponds. Many of these habitats were vegetated and the associated vegetation included many types of 水生植物 单子叶植物 (e.g. "纸莎草", "藨草属" sp., "香蒲属" sp., "芦苇属" sp.) and 双子叶植物 (e.g. "金鱼藻", "菹草", "延药睡莲"). Where densities are high, "Tarebia granifera" may also occur on marginal, trailing vegetation and the floating Common Water Hyacinth "凤眼蓝" as well. It favours turbulent water and tolerates current speeds up to 1.2m.s and possibly greater. This habitat range is similar to that recorded for "Tarebia granifera" in Puerto Rico.
title: Dispersal.
content: It is probable that 扩散 (生态学) of "Tarebia granifera" from one waterbody or river catchment to another occurs passively via birds, notably 雁形目, which eat them and void them later, perhaps in another habitat. Evidence for this comes from the finding of many small "Tarebia granifera" 5–7 mm in height and still containing the soft parts in unidentified bird droppings from the bank of the Mhlali River, South Africa. Even though the shell of "Tarebia granifera" is thick, most of these juveniles had been partially crushed with only a few still intact. Both the intact and damaged specimens could have been alive when passed and perhaps survived had they been deposited in water. None was large enough to have been reproductively mature (see below) and would have needed to survive in any new habitat for several months before reproducing.  The low densities of "Tarebia granifera" reported for the Mhlatuze River, South Africa may have been influenced by nearby sand mining activities or, more likely, high flows and mobile sediments, but they nevertheless approach those recorded by Dudgeon (1980) for "Tarebia granifera" in its native 香港 (18–193 m).
title: Life cycle.
content: "Tarebia granifera" is both 单性生殖 and 卵胎生, although males have been reported. These are characteristics which are undoubtedly key to its success as an invader. For example, no males have been found amongst hundreds dissected from KwaZulu-Natal, it is probable that a few are present. Males were found in most (6/7) populations examined in 波多黎各 but were generally uncommon at up to 22.7% of the population (mean 4.6%). Live sperm were present in the testes of these males but the genitalia were apparently non-functional. R. Tucker Abbott (1952) failed to find sperm in the gonads of male "Tarebia granifera" from Florida. Most "Tarebia granifera" are therefore 克隆 of the female parent.
title: 寄生虫.
content: 本物种在东南亚为多个吸虫纲物种的中间宿主,当中有多个物种属于Heterophyidae科,而且有报告指部分物种对人类可进行机会性感染 and another, "Centrocestus formosanus" (Nishigori, 1924), is an important gill parasite of fish. "Tarebia granifera" also serves as intermediate host for the philopthalmid eyefluke "Philopthalmus gralli" Mathis & Ledger, 1910 which has recently (2005) been reported affecting 鸵鸟科es "鸵鸟" on farms in Zimbabwe. The snail host implicated in this outbreak was "Melanoides tuberculata" but the rapid spread and high population densities achieved by "Tarebia granifera", which appears to be replacing "Melanoides tuberculata" in South Africa, may exacerbate the problem in the future.  Anecdotal reports and observations suggest that in 夸祖鲁-纳塔尔省 the indigenous thiarid "瘤拟黑螺" is becoming less common and pressure from the spread of "Tarebia granifera", particularly at high densities, is a possible explanation. Like "Tarebia granifera", "Melanoides tuberculata" is parthenogenetic and ovoviviparous, grows to a similar size, are similar in size at first birth and juvenile output. Data from several habitats where the species occur sympatrically show however that in all such situations "Tarebia granifera" becomes numerically dominant.  Studies on the ecological impact of "Tarebia granifera" are urgently needed.

Summary: 瘤蜷(学名:'),又名斜粒粒蜷,是锥蜷科粒蜷属的一种有口盖的淡水螺物种,属于水生腹足纲软体动物。原生于东南亚,本物种在墨西哥等地泛滥,成为了入侵物种。

Tarebia granifera: Tarebia granifera, common name (in the aquarium industry) the quilted melania, is a species of freshwater snail with an operculum, an aquatic gastropod mollusk in the family Thiaridae. This snail is native to south-eastern Asia, but it has become established as an invasive species in numerous other areas.