印度扁卷螺

分類

儘管本物種有著悠久的歷史和廣泛的地理分布範圍，牠們一直都被認為是屬內唯一的物種；而過往亦有文獻建議本屬跟其他關係較密切的屬合併。然而，Liu et al. (2010)根據系統地理學研究，發現在系統發育方面，印度分支和東南亞分支之間有相當的分歧；加上棲息地和寄生蟲學的差異，表明這個物種實際可能由多於一個物種構成。
從系統發育的角度看，與本屬關係最密切的是Bulinus屬。

分布

印度扁卷螺本身是一種淡水螺，在中亞的伊朗與阿富汗，南亞的印度、尼泊爾及斯里蘭卡均見其蹤影。在東南亞，例如：泰國)，甚至遠至阿拉伯地區及非洲均見其蹤影。
The type locality of Indoplanorbis exustus is marshes on the coast of Malabar in southwestern India.
Indoplanorbis exustus is a common snail across Southeast Asia and the Indian sub-continent. The snail is also found in the Middle East (Oman and Socotra) and Nigeria and the Ivory Coast; these findings were attributed by Brandt (1974) to recent introductions by human activities (Brandt's view has been frequently cited in the literature on Indoplanorbis). In contrast to Asia, the well documented appearance of the snail in Africa (e.g., Nigeria and Ivory Coast) and more recently (2002) in the Lesser Antilles, is almost certainly the result of introductions through human activities over the last 50–100 years.
This species is already established in the USA, and is considered to represent a potentially serious threat as  a pest, an invasive species which could negatively affect agriculture, natural ecosystems, human health or commerce. Therefore it has been suggested that this species be given top national quarantine significance in the USA.

生物地理學

Meier-Brook (1984) adopted an African (Gondwanan) origin for Indoplanorbis with rafting to Asia since the Cretaceous on the northward migrating Indian craton; this author also considered a Europe to Southwest Asia tract or an Africa to South India dispersal. Morgan et al. (2002) attributed the occurrence of Indoplanorbis in India to colonization (from Africa) via the Middle East land connection. Clearly the two different dispersal mechanisms imply very different chronologies; the Gondwanan vicariance hypothesis implies that proto-Indoplanorbis has been present in India since the late Eocene (35 Ma; India: Asia collision), whereas dispersal via
the Sinai-Levant suggests a Plio-Pleistocene arrival. The results by Liu et al. (2010) indicated a radiation beginning in the late Miocene with a divergence of an ancestral bulinine lineage into Assam and peninsular India clades. A Southeast Asian clade diverged from the peninsular India clade late-Pliocene; this clade then radiated at a much more rapid pace to colonize all of the sampled range of Indoplanorbis in the mid-Pleistocene.

生態學

當印度扁卷螺被圈養時，可以以萵苣及菠菜來圈養。有時候其膳食會輔以羊肝，在繁殖時可提供一般寵物鼠的食糧。

Habitat

The snail is found in small ponds, pools, and less commonly in rice paddy fields. The snail may also occur in semi-permanent pools formed in flooded areas of fields, where it can survive the dry season buried in mud. The desiccation tolerance of adult snails is high, while the resistance of juvenile snails is very low. Consequently, dispersal may occur in clumps of mud adhered to the bodies of cattle or across water in vegetation mats. It is possible it could be transported by birds.

Life cycle

Indoplanorbis exustus is a hermaphroditic invasive snail species with high fecundity. Within one year of introduction the snail is able to colonize habitats with well established populations of other pulmonate and prosobranch snails. The snail requires a water temperature in excess of 15 °C for maturation. At the optimum temperature of 30 °C each snail can lay up to 800 eggs. There is from 2 to 43 eggs in one cluster with an average 20 eggs in one cluster. The capacity for self-fertilization and high fecundity probably underlies the invasive potential of the species. The average life span of Indoplanorbis exustus is 4 months and during this time it lays about 60 egg clusters.

捕食者

現時本物種並沒有已知的天敵，不過有文獻透過實驗去測試一些物種會否進食印度扁卷螺的卵。Raut & Aditya (2002)在實驗裡讓一種屬於南美洲福壽螺科的Pomacea bridgesii去攻擊和進食印度扁卷螺的卵，以期望未來可以讓這種福壽螺來控制印度扁卷螺的數量。

毒理學

一種在印度生長的大戟科植物紅雀珊瑚（Pedilanthus tithymaloides）可用作植物性殺螺劑，有助對抗印度扁卷螺。
黃果茄的酒精提取物亦可對本物種（LC₅₀ = 198.00 mg/L and LC₉₀ = 236.80 mg/L）。
此外，另一種大戟科物種虎刺梅（Euphorbia milii），其雜交物種株的乳汁對於本物種的活躍度有所抑制，也可作殺螺劑使用。除了虎刺梅的雜交種，印度的科學家Singh & Sunil在2005年發表的文獻亦研究過黃花夾竹桃（Cascabela thevetia）、黑板樹（Alstonia scholaris）兩種夾竹桃科植物及另一種較常見的大戟科植物一品紅（Euphorbia pulcherrima）的乳汁對印度扁卷螺的抑制效果。