Resumen

JARA-SEGUEL, Pedro; PEREDO, Santiago  y  PARADA, Esperanza. RECORD OF POLYPLOIDY IN THE FRESHWATER CLAM MUSCULIUM ARGENTINUM (D'ORBIGNY 1835) (SPHAERIIDAE, VENEROIDA). Gayana (Concepc.) [online]. 2005, vol.69, n.1, pp. 36-40. ISSN 0717-6538.  doi: 10.4067/S0717-65382005000100006.

The polyploidy is an unusual character in bivalve mollusks. However, cytogenetic data documented for north-hemispheric species of the subfamily Sphaeriinae (family Sphaeriidae), showed chromosome numbers ranging from 36 to ca. 247. The freshwater clam Musculium argentinum (D'Orbigny 1835) has a polyploid chromosome number 2n = ca. 130, which shows that polyploidy likewise may be present in South American sphaeriids. These cytogenetic data suggest that the subfamily Sphaeriinae could constitute a mature polyploid complex

Palabras clave : Sphaeriidae,; Musculium argentinum; polyploidy; polyploid complex.