Dimensions of adult shell 2.2x1.5 mm to 2.5x1.6 mm. Protoconch paucispiral, clearly separated from teleoconch, with 1 1/4 whorl, strongly lirate with an apical carina giving a characteristic truncated outline, Teleoconch with 3 3/4 to 4 whorls. Sculpture strongly clathrate; a very tenuous spiral microsculpture can be seen under SEM observation. Whorls with two very coarse beaded cords (a third one concealed by the suture) intersecting with axial ribs. Body whorl with five spiral beaded cords, the most anterior forming a beaded ridge; there is a vestigial sixth cord next to the aperture. Aperture with very thick outer rim, strongly indented by termination of the cords, internally with 5-6 faint denticles reaching far inside. Shell colour tawny, with paler anterior foremost cord and apertural rim. Head with bilobed snout, and tiny jaws seen by transparency; buccal mass indistinct. Tentacles slender and tapering, colourless. There are two distinct, elongated yellow stains behind the eyes. Foot with distinct anterior pedal gland and short, triangular metapodial tentacle. There are two folds, one on each side behind the head, forming neck lobes, and opercular lobes with whitish specks on their anterior part. Pallial tentacles are both moderately large and colourless.

This species has been assigned to Manzonia by Amati (1987) following the conchological criteria of Ponder (1985), especially owing to strong anterior spiral cord on the body whorl, I find more parcimonious to hold it as congeneric with Alvania cancellata, a species where the metapodial tentacle is typical for Alvania but otherwise shares many characters with A . sleursi; sculpture, microsculpture head-foot morphology (except metapodial tentacle). Similarity is such that the possibility of A. sleursi being derived from A. cancellata with loss of planktotrophy must be considered.
This species was overlooked by Dautzenberg (1889) and was described after specimens of his collection- Other specimens in MOM are variously identified as Alvania hirta var. minor (st. 193, 218, 703) or A, zetlandica (st, 112). I did not find A. sleursi in its type locality.