Cornu aspersum (O.F. Müller, 1774) is a common European snail with a ground colour of yellowish brown , and mostly with some darker spiral bands and irregular light and dark blotches (Jansen, 2015). Recently in a Dutch zoo a new tropical greenhouse was installed with plants imported from Costa Rica. Herman Creemers sent me a picture of snails collected in this greenhouse (on the right side), together with some specimens from the Netherlands (on the left side). He wondered if this species was known from Costa Rica or not.
Barrientos (2003) has given an overview of Costa Rican species and said: “El escargot, Helix aspersa [the old name], fue introducido has más de 100 años y está restringido a jardines urbanos en San José”; the species is thus more than a century present in Costa Rica, but still restricted to gardens in the capital. The different coloration of shells presumably originating from Costa Rica, imported together with plants, is somewhat different. This might be due to the prolonged isolation, but only detailed DNA research could tell whether some divergence has occurred or not.
Barrientos, Z., 2003. Estado actual del conocimiento y la conservación de los moluscos continetales de Costa Rica. – Revista de Biologia Tropical 51, Supplemento 3: 285–292.
Jansen, A.W., 2015. Veldgis slakken en mossels. Zeist, KNNV, 272 pp.