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Gyraulus
''Gyraulus'' is a genus of small, mostly air-breathing, freshwater snails, aquatic pulmonate gastropod mollusks in the family Planorbidae, the ram's horn snails. The genus ''Gyraulus'' is known from the Early Cretaceous to the present. Fossils attributed to ''Gyraulus'' sp. have been found in the lakebottom sediments of the Yixian Formation in China, dating to 125 million years ago.Pan, H. and Zhu, X. (2007). "Early Cretaceous non-marine gastropods from the Xiazhuang Formation in North China." ''Cretaceous Research'', 28(2): 215-224. The minute species ''Gyraulus crista'', although technically a pulmonate gastropod, does not use air for respiration, but instead has a mantle cavity which has much water. Distribution The distribution of this genus is Holarctic. Habitat These snail snails live on water plants in freshwater. Shell description Shell of the species within this genus are small, and are mostly almost planispiral in their coiling. Species Species within the ge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gyraulus Cristaeformis
''Gyraulus'' is a genus of small, mostly air-breathing, freshwater snails, aquatic pulmonate gastropod mollusks in the family Planorbidae, the ram's horn snails. The genus ''Gyraulus'' is known from the Early Cretaceous to the present. Fossils attributed to ''Gyraulus'' sp. have been found in the lakebottom sediments of the Yixian Formation in China, dating to 125 million years ago.Pan, H. and Zhu, X. (2007). "Early Cretaceous non-marine gastropods from the Xiazhuang Formation in North China." ''Cretaceous Research'', 28(2): 215-224. The minute species ''Gyraulus crista'', although technically a pulmonate gastropod, does not use air for respiration, but instead has a mantle cavity which has much water. Distribution The distribution of this genus is Holarctic. Habitat These snail snails live on water plants in freshwater. Shell description Shell of the species within this genus are small, and are mostly almost planispiral in their coiling. Species Species within the genus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |