Apex. Shape: moderately convex.
Spire. Height: 1.6–1.7 mm. Width: 1.3–1.4 mm. Number of whorls: 4–4 1/4. Apical spire shape: depressed. Basal spire shape: conical. Whorl periphery: moderately convex. Umbilicus: open.
Constriction. Parietal teeth: two. Basal teeth: none.
Tuba. Coiling direction: type 2 and aperture visible in right lateral view. Tuba whorl length in proportion to spire last whorl: ca. 5/8 of the spire last whorl length. Proportion of tuba that attaches to spire: less than 1/3.
Aperture and peristome. Peristome: double peristomes. Outer peristome shape: similar to inner peristome, projected all around, except the posterior part, where the left lateral sides are slightly more projected than the anterior and right lateral side.
Spiral lines. Thick lines: absent. Thin lines: present.
Radial ribs. Rib density: 6–7 ribs per mm. Rib intensity: thin. Shape: slightly curved. Inclination: moderately prosoclin.
Critically Endangered (B2ab(iii)+C2a(i) ver. 10.1). The entire Bukit Tenggek will be gone by 2014 because of quarrying activity.
Holotype: BOR 5650(1). Paratypes: V 13554(5), BOR 444(4), BOR 5596(>10).
See discussion under Plectostoma praeco.
Type locality. Bukit Tenggek, Pahang (4°0'51"N, 103°9'34"E).
Distribution range. Endemic to type locality (Figure 18B).