Planorbis meridaensis Preston, 1907 (Gastropoda: Planorbidae), a synonym of Biomphalaria prona (Martens, 1873)

• Main Author: W. Lobato Paraense
• Format: Article
• Language: English
• Published: Instituto Oswaldo Cruz, Ministério da Saúde 1992-12-01
• Series: Memórias do Instituto Oswaldo Cruz.
• Subjects: Gastropoda Planorbidae; Planorbis meridaensis; Biomphalaria prona; morphology; synonymy; Venezuela
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0074-02761992000400013

Biomphalaria prona from Lake Valencia, Venezuela (type locality) has a polymorphic shell wich in the great majority of specimens is wider, with fewer rapidly expanding whorls, the outer one subcarinate on the left side and more or less strongly deflected leftward. Besides those modal forms there are little frequent variants characterized by narrower shell with less rapidly expanding, regularly curved whorls directed forward. Recent studies have shown that such variants constitute the predominant shell phenotype in extralacustrine populations, but are anatomically and biochemically indistinguishable from the modal class of the Lake. In the present paper it is demonstrated that the nominal species Planorbis meridaensis Preston, 1907, from Mérida, Venezuela, is identical with B. prona (Martens, 1873) of wich it must be considered a junior synonym.