Taxon classification Animalia Stylommatophora Amphibulimidae

Plekocheilus (Eurytus) oligostylus Pilsbry, 1939 Figs 10 A–B, 14

Plekocheilus oligostylus Pilsbry 1939: 3, fig. 6.

Plekocheilus jimenezi; Richardson 1995: 315 (references, excl. synonymy).

Plekocheilus (Eurytus) jimenezi oligostylus; Breure and Borrero 2008: 6.

Type locality.

“Colombia”, see remarks.

Type material.

ANSP 170696, lectotype (Baker, 1963).

Diagnosis.

Shell relatively large, solid, with oblique series of more or less spirally arranged reddish-brown spots, evenly and dense granulation, suture somewhat descending in front, aperture ovate.

Dimensions.

Shell height 71.0, diameter 47.0 mm.

Distribution.

Ecuador, Prov. Napo, Nachiyacu; ibid., Sarayacu; ibid., valley Río Quijos; Prov. Pastaza, Puyo; ibid., Mera (all Breure and Borrero 2008).

Ecoregion.

Eastern Cordillera real montane forests [NT0121].

Remarks.

Clench and Turner (1962: 109) have pointed out that the original locality was erroneous; the type locality should be Nachiyacu. This taxon has been synonymized by Richardson (1995) with Plekocheilus (Eurytus) jimenezi, but without any comments. The shape of the aperture in the type specimen may not be entirely typical; it does not show the ascending suture behind the lip typical of Plekocheilus (Eurytus) jimenezi, and the aperture is different in shape. Tentatively we have retained this taxon as a separate species, as it may be sympatric with Plekocheilus (Eurytus) jimenezi, awaiting further studies in the area.