微小貝




微小貝（Micromollusk），亦作迷你貝，是指一些即使成長後其體積依舊非常細小的有殼腹足綱軟體動物。
日本有學術機構在互聯網上建構有微小貝數據庫[1]，以協助搜集有關微小貝相關的數據，如型態特徵等。目前紀錄有約8600個物種[1]。




目录






  • 1 具體定義


  • 2 參考文獻


  • 3 參看


  • 4 外部連結





具體定義


其實現時並未有對微小貝的普世認同標準，所以這個定義有時隨不同學者的定義而有所不同。不過，普遍接納標準的上限在於5 mm到7 mm之間，對應英美制的四分一英寸。
對於殼長不超過10 mm，殼寬在5 mm以內，這個尺度的貝殼一般都需要20倍的放大鏡才可以看得清楚其細節[2]。而對於5 mm以下的，就必須要顯微鏡才可以清楚看見其紋理。


現時最細小的貝類，其長成大小也不超過1 mm，甚或比一般的沙粒（英语：sand grain）還要小。對於體長2 mm到4 mm的，即使用小手捧着，也會從手指間漏出。這些微小貝在採樣時，一般都要靠篩子將牠們從沙泥出篩走。



參考文獻





  1. ^ 1.01.1 微小貝データベース [微小貝數據庫]. [2018-01-17] （日语）. 


  2. ^ 葉人驥. 美哉迷你之貝. 貝友. 1996, 22: 27–31 （中文（繁體）‎）. 





參看


  • 鳴砂


外部連結








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