Pandalosia excelsis: Shell small, elongate, conical, white, shining, and translucent. Protoconch slender, of 2,5 whorls, the nucleus large, sculpture beginning gradually on the 3rd whorl. Mature whorls 6, short, rounded, sutures deeply impressed. Sculpture of large, rounded axial ribs, curved and oblique, 14 on the body and penultimate whorls, fewer on the earlier whorls. Aperture semicircular, anteriorly and laterally extended, very oblique, the anterior margin thrust forward, varix very heavy, widest over the columella, where it is indented by the termination of the axial ribs, inner margin only slightly arched. Length 3-,7 mm.
Localities.—Murray I. (C. Hedley), holotype and 5 paratypes; Barrier Reef off Cairns (D. Pitt, C46088 in Australian Museum).
Remarks.—This beautiful little species has been selected as the type of the genus, as it shows perfectly all the characters considered to be of generic value.

Rissoina decapitata: Shell small, conical, heavy, white and translucent, shining. Apex truncate, at first sight appearing broken, close microscopic examination only revealing the protoconch as a relatively large nucleus immersed in the summit. Mature whorls 5, increasing regularly, rounded, restricted at the sutures. Sculpture of strong, rounded, oblique axial ribs, very close together, about 16 to the whorl. Basal fold strong, indented by the termination of the axial ribs. Aperture semicircular, large, laterally extended, oblique, the anterior margin thrust well forward. Varix heavy, columella sinus shallow but distinct. Length 3,2 mm.
Locality.—Michaelmas Cay, holotype and 3 paratypes.
Remarks.—The small size, the large expanded aperture, the close axial ribs, and the peculiar protoconch separate this at once from all the previous species.

AS: Pandalosia darwinensis Laseron, 1956
Diagnosis: Shell, small, white, subpellucid elongate with turreted spire. Mature whorls, 5-6, flatly convex. Raised ribs, slightly oblique from suture to suture or to the base without spiral straie; about 14 ribs on the penultimate whorl. Aperture, semicircular; outer lip, variced thickly over anterior end becoming nodular on columella, but open at parietal wall.
Distribution: Darwin, Australia is its fatherland and it is also found of Lutao, Taiwan.
Dimension: 3.2 x 1.4 mm.
Remarks: This is a new record in Taiwan.
Reference for Identification: Laseron (1956), Fig. 6.

Pandalosia darwinensis: Shell small, slender, conical, white, glassy, and translucent. Protoconch slender, of 2,5 rounded whorls, nucleus large, practically identical with that of P. excelsis. Mature whorls 5, rounded, sutures deeply impressed. Sculpture as in P. excelsis, but the axial ribs are smaller. They also number 14 on the body and penultimate whorls. The aperture is also similar to that of P. excelsis, but is not quite so thickened on the outer margin, and the varix is even more widely extended over the columella. Length 3,4 mm.
Locality.—Darwin (J. Laseron), holotype and 6 paratypes.
Remarks.—This is so close to P. excelsis that opinions might differ as to whether the differences are fully specific or merely racial. In all the specimens examined, however, the characters are constant, P. darwinensis has 1 whorl less, is smaller, and the aperture is slightly different.