Dimensions of adult shell 1.1x0.7 to 1.4x0.8 mm. Protoconch 1 1/4 whorl, with microsculpture of 4-5 faint spiral threads and a brown apical stain; separated from, teleoconch along a faint line. Teleoconch with 3 whorls, translucent, indistinctly corrugated by the growth lines. Aperture slightly widening, smooth within, somewhat thickened externally. Shell colour horny, with two series of vertical flames; columella and posterior part of the outer lip also stained with brown.
Head with bilobed snout; tiny jaws and colourless buccal mass seen by transparency. Tentacles quite thick, parallel sided, with axial yellow solid line. There are two elongated yellow patches to the inner side of the eyes. Foot slender, with clearly visible anterior pedal gland, and laterally two black stains anterior to the metapodium. There is a single, well developed metapodial tentacle, elongately triangular in shape. Opercular lobes stained with black anteriorly. No pallial tentacles could be seen; the mantle has a series of yellow spots arranged spirally and visible through the shell by transparency.

This species resembles some Setia from the European mainland [as S. amabilis (Monterosato in Locard, 1886) as defined by Verduin 's (1984) lectotype, and several of the taxa introduced by Verduin (1984)S.sliki,S.aartseni and S.gittenbergeri. It is not within the scope of this paper to revise these taxa, but the Azorian species differs from all Mediterranean or Atlantic European Setia I have seen by the distinctly thickened outer lip of adults. Nordsieck's name elongate is not available, as originally introduced as infrasubspecific.
The character of the aperture, with thickened lip, is more like Pusiliina or Rissoa than typical Setia, but other characters of S . subvaricosa (no pallial tentacles, spiral threads of the protoconch) ressemble the type species Setia pulcherrima (Jeffreys, 1848).
"Rissoa" quisquiliarum Watson, 1886, type species of Varisetia Nordsieck, 1972 is a distinct species found only on the central group of islands. Type locality is off Faial, 38° 38' N, 28° 28' 30" W, in 730-910 m; the holotype is quite worn. Specimens from Terceira in A. M. Frias Martins collection differ in more conical outline, more convex whorls and distinct spirals on the anterior part of body whorl; the varix is also thicker.
Nordsieck's specimen labeled as Putilla (Varisetia) quisquiliarum (Watson, 1886), Ponta Delgada" is smooth and probably not conspccific with true "R. quisquiliarum from the central group of islands.However, Nordsieck's (1972: 159) description mentions a spiral sculpture. All shell characters support Ponder's (1985) view that Varisetia is a synonym of Pusillina.