Shell discoid, depressed, almost planispiral, fragile, with very small prominences on a keeled periphery. Protoconch of about 1,5 smooth whorls, between 410-450 µm diameter, as mentioned in the original description, but we have a shell with a diameter of 470 µm. Teleoconch of about 1,5 whorls, increasing rapidly, dorsally with numerous fine oblique axial ribs and two spiral cords, one of them always well-marked; ventrally the axial ribs are very prominent and sharp, one spiral cord is near the peripheral keel, delimiting a depressed area. Another slight cord, sometimes little evident, is between that one and the umbilicus, which is very wide showing the previous whorls. Aperture oblique, with a sharp edge in the outer lip and a continuous peristome. Under magnification can be seen tubercles grouped in bands. Dimensions: The holotype is 3.0 mm in diameter. In our material, the largest are of that size.

The shell of T. mienisi is rather similar to that of Discopsis costulatus, but is not so depressed, the dorsum presents two spiral cords, one of them always well-marked and there are another two on the ventral part. The basal axial ribs are very prominent in T. mienisi but not in D. costulatus. Furthermore, the peripheral border is not regular and has very small prominences in T. mienisi.

Known only from Israel and Turkey