Acteon biplicatus (Strebel, 1908)

Fig. 5B

Odostomia biplicata Strebel, 1908: 65, pl. 1, figs. 9, 9a

Actaeon biplicatus — Castellanos & Landoni, 1986: 297, fig. 13

Examined material. 1 an. and 38 sh. (MACN-In 40698).

Description. Shell height to 5.5 mm; elongate-conical, delicate. Protoconch large, smooth, of about 1.75 slightly convex whorls; transition to teleoconch poorly defined. Teleoconch with up to 4 whorls, slightly convex in outline; last whorl comprising about 70% of total shell height. Suture deep, slightly channeled. Surface brownish, with a pale band below suture; only sculptured with faint growth lines. Aperture ovate, interior pale brown; columella with two small folds, callus moderately thick, slightly expanded over the umbilical area.