Shell description
The shell is external and white to transparent in colour, usually with a cylindrical elongate shape; the front part is rounded in outline when viewed from above. The opening is large, and extends the length of the shell. The oldest part of the shell (protoconch) extends slightly further out of the shell. The shell is umbilicated. The shell surface is smooth, with faint growth lines. The length of the shell is around 3 mm.

Animal description
This species has no visible eyes and the foot is not forked in the hind as in other species of the genus.

Anatomy
The radula is symmetrical and each row has one outer lateral tooth and one inner lateral on each side, and one central (rachidian) tooth. The male reproductive system consists of a short elongate penis chamber, with a short hook-shaped prostate; sometimes a second prostate branch may be present. This species is unique among Scandinavian species as it lacks a forked foot and as outer lateral teeth present.

White, cylindrical to oval shell with acuminate spire and unrimmed groove between whorls. In¬ner lip simple, elongated, inverted S-shaped. No groove in columellar lip. Radula with marginal teeth. Shell, general: Cylindrical to oval, widest part between 1/4 and 3/4 of the height from base, smooth except for fine growth lines. Transparent to white. Height to at least 2.8 mm. Height/width 1.53-1.87. Between 13 and 1.4 teleoconch whorls on a 2 mm high specimen. Spire: Acuminate with protoconch projecting. Shoulders rounded, separated from the preceding whorl by unrimmed groove. Aperture: 75-85% of shell height. Widest 1/5 to 1/4 of its height from the base. Outer lip evenly rounded in lower 1/4 to 1/3 of shell, running straight or almost straight above until it forms a small arch at top. Inner lip following a shallow, even curve from top of aperture to about halfway to base, where it joins the columella at an angle of 180° and follows another shallow, even curve in the opposite direction as before. Umbilicus: Open, 2-3% of shell width, with¬out abapertural rim.
Protoconch: Elongated lecithotrophic type, smooth, 0.5-0.7 mm wide, with about 0.7 whorls. Angle between protoconch and teleoconch axis 110-140°.
External anatomy: Foot large and fleshy, unforked posteriorly. Eyes not visible.
Radula: Formula 1.1.1.1.1, symmetrical; marginal teeth with a narrow base.

Type locality
Laptev Sea, 78°13’N-142°13‘E, 57 m. Known from the Laptev Sea at depths of57-231 m and the Kara Sea at a depth of 125 m (Gorbunov 1946a-b, Chaban 1996a-b, present study), NE Greenland at depths of 9-52 m (Schiotte 1989), the continental slope N of the Faroe Islands and Iceland, at depths of 437-1400 m (Schiotte 1992 and present study), the latter occurrence stretching onto the top of the Iceland-Faroe Ridge. Occurs in Greenland, the continental slope north of the Faeroe Islands and Iceland, the Kara Sea and Laptev Sea. D. makarovi is apparently strictly bound to Arctic water and is not a true deep-sea species, but follows the cold water masses into bathyal depths on the slopes around the Greenland Sea/Norwegian Sea.
Ecology
Occurs at depths between 9–1400 m on clay, clay with sand, mud, sand and silt with foraminiferans and sandy mud. D. makarovi lays large eggs with a diameter of about 0.6 mm, and the young ofthe species hatch as crawling specimens with an operculum. They retain their operculum until they have reached a shell height of at least 12 mm.