First record of colour polymorphism in the Neotropical apple snail Asolene platae: inheritance mechanism and evidence for sperm competition

TIECHER, MARÍA JOSÉ; BURELA, SILVANA; MARTÍN, PABLO RAFAEL

MOLLUSCAN RESEARCH

MAGNOLIA PRESS

Lugar: Auckland; Año: 2017 vol. 37 p. 187 - 193

1323-5818

Asolene platae (Ampullariidae) is a dioecious freshwater snail with subaquatic gelatinous egg masses that dwells in the Río de la Plata basin (Argentina). Our aim was to describe the inheritance mechanism of the colour variations of the shell and soft parts of this snail and to study their potential use as a genetic marker. The wild phenotype (W) presents dark pigments in the soft parts and in shell bands whereas the yellow phenotype (Y) lacks dark pigments in the soft parts and also most dark bands in the shell, except for a subsutural and a periumbilical band. Our data showed that the lack of pigments in A. platae is a recessive homozygotic condition with a simple Mendelian inheritance mechanism. Females of the W phenotype had a higher number of bands than the males. The pigment of the bands of both phenotypes is located in the calcareous matrix of the shell. Using the lack of pigments as a genetic marker we demonstrated the existence of biparental egg masses and the occurrence of sperm competition in A. platae, which hitherto were known only one species within the Ampullariidae.