The family Kelliellidae (Bivalvia: Heterodonta) from the deep Atlantic and its relationship with the family Vesicomyidae

The shell form and internal morphology of ten species of the family Kelliellidae from the deep Atlantic (>500 m) are described. The descriptions include those of five new species: Kelliella concentrica, K. elongata, K. abyssicola, K. biscayensis and K. tenina. Small, fragile, chordate species previously included in the genus Vesicomya, are referred to Kelliella, and their inclusion in the superfamily Glossoidea is confirmed. Their relationship with the large, elongate, chalky shells of the genus Calyptogena and its relatives is discussed and it is concluded that the latter are distinct, at least, at subfamilial level. (C) 2001 The Linnean Society of London.