MUSEO ARGENTINO DE CIENCIAS NATURALES "BERNARDINO RIVADAVIA"
Unidad Ejecutora - UE
Neactaeonina argentina (Mollusca, Gastropoda): new species, and family placement of the genus Neactaeonina Thiele, 1912 (Mollusca: Gastropoda)
ZELAYA, D. G.; ITUARTE, C.
Año: 2011 vol. 53 p. 251 - 251
Neactaeonina argentina, a new species from the outer Argentine shelf, off Buenos Aires province, is described. The species is characterized by the elongate, low-spired shell, with shouldered, nearly straight whorls, suture deep, and sculpture composed by numerous, broad and flat spiral cords. The radula is similar to that previously described for the type species, Neactaeonina cingulata Thiele, 1912, except in having a higher number lateral teeth. The study of anatomical characters, not known to date, showed that Neactaeonina have clear affinities with the Acteonidae, with a combination of features present in Acteon (as the presence of a well-developed operculum, mantle cavity opening anteriorly, nervous system with only the cerebro-pleural ganglia fused, presence of a pouch-like stomach, a single allosperm sac associated with the female system, and oral cuticle with rod-like processes; and some characters present in ?acteonid? genera other than Acteon (e.g.: the number and morphology of teeth, and processes of the oral cuticle). However, Neactaeonina shows some characters thus far not reported for any other genus currently placed into the Acteonidae: salivary glands with laminar structure, male genital system with an open portion, a single allosperm sac opening distally, and a flat and triangular copulatory organ.