Descripción Del Desarrollo Embrionario De Physa Cubensis (Pfeiffer, 1939) (Pulmonata: Physidae), en La Sabana De Bogotá, Colombia

Abstract

The embryonic development of Physa cubensis (Pfeiffer, 1939) mollusk is described. The collection of eggs took place in different bodies of water from the savanna of Bogotá, Colombia during 2017 and 2018 in the months of November to April. Searches were made among the leaves and stems of macrophytes, as well as sticks and stones. A total of 70 egg laying sites were identified and about 858 eggs were evaluated. Nine embryonic stages were identified: fertilized egg, cleavage of two cells, four cells, eight cells, thirtytwo cells, initial and late blastula, initial and late gastrula, Trochophore and veligers larvae. These freshwater organisms, due to their rapid embryonic development, as well as the large number of eggs deposited during each spawning, demonstrate overpopulation, and thus potential for becoming a pest.