GASTROPODA | HELICONOIDAE |
The shell differs from those of Limacinidae by its planar development. |
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Heliconoides d’Orbigny, 1836:Shell close to those of Atlanta, with the first whorls depressed on both sides, but without a laminar hull on the periphery; certainly the whorls expand radially, but also, and most importantly, quickly they begin to widen transversely, so that the aperture can become wider than high. |
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