Type locality: Nosy-Be, northwest of Madagascar.
Range: This species has a highly restricted range. It is only found on the beach of Nosy-Be and a few adjacent sites. The Seychelles and Comores have never been a part of its range. Habitat: From the intertidal zone to just below, buried in sea grass patches.
Description: Shell is of medium size, fusiform, light but solid, measuring 50-60 mm. Protoconch is small, orange coloured, of two smooth whorls of 2.1 mm in diameter. Spire is moderately high. Teleoconch with six slighty convex whorls. Sculpture of 25 to 27 closely spaced sharp axial ribs, leaving a narrow intercostal space marked by fine spiral striations. Aperture with a half-moon shape measuring 0.61 of the total length. Outer lip is thickened forming externally a sligthty marked varix.
Columella is arched bearing 3 strong plaits followed adapically by 13-15 weaker folds. Siphonal notch is narrow and shallow. Background colour is creamy with eight spiral brown lines which appear mainly on the lip, masked by large red-orange stains which often cover the entire surface of the body whorl. Aperture is porcellanous white.
A small separated population from Pointe Ankify slighty differs by a deep red colouration and a stockier shape. Animal: Foot and head are whitish and strongly marbled with brown blotches. The edge of the foot and the tip of the siphon are encircled with a black ring, fringed with white. Radula tricuspid with 48-53 rows of teeth.
Comparison: L. (L) tulearensis is the closest related species, and for a long time was considered a subspecies. It differs consistently by a stockier shape, less numerous (17-20) and heavier axial ribs, a pattern formed by black spiral lines, very pronounced on the external edge, the siphonal band and edge of the siphonal notch well marked with black stains.
Remarks: A very common shell, abundantly sold in the local markets as a souvenir for tourists. However its narrow localized distribution makes it fragile and easily menaced by anthropic damage to its shallow water habitat and by excessive local fishing.
Some very big specimens, up to 80 mm long, are seen in very old collections. Such a size is never found now, probably because of current over-collecting.

TYPE: The whereabouts of the specimen described in the Magasin de Zoologie is not known to the authors. TYPE LOCALITY: Nosse-Bé, on the northwest coast of the island of Madagascar, now called the Malagasy Republic. RANGE: From Madagascar north to the Comoro Islands and the southern Seychelles, covering a radius of approximately 200 miles. HABITAT: Information not available. DIMENSIONS: Adult specimens are 42 to 55 mm in length. SHELL DESCRIPTION: Shell is of medium size. It is solid and fusiform, with an attenuated spire. Protoconch is globose, of two brown, smooth whorls. Teleoconch has about five and a quarter heavily sculptured whorls. The entire shell is sculptured with numerous, narrow, sharp axial ribs. There are about 18 such ribs on a specimen 48 mm in length. Suture is deeply indented. Aperture is rather narrow; interior shiny white. Just outside the leading edge of the outer lip is a wide, low ridge running parallel to it. Columella is slightly arched and covered by a thin, white glaze. Numerous plaits almost cover the entire columella and parietal area; the three anterior ones are strongest. Siphonal notch is narrow and deep; fasciole weak. Base color is flesh, profusely clouded with orange-red and marked spirally with fine, chestnut or rust-red interrupted lines running parallel to each other about 2 mm apart. Horny operculum is present. ANIMAL AND RADULA: Not available for study. REMARKS: This species is related to Lyria mitraeformis (Lamarck, 1811) but differs from it in the following ways: the spire is more acuminated, there are more and narrower axial ribs, and the columellar plaits are stronger. The small, posterior, columellar toothlike projection found in mitrae- formis is absent in delessertiana. This uncommon species was named for Baron Jules Paul Benjamin Delessert.