Diagnosis
Shell small, stout, fusiform, heavily sculptured, with very long siphonal canal. Protoconch conical, with -2.7 light gently convex, glossy whorls. Teleoconch whorls convex to almost subcylindrical, with well-developed, though narrow, subsutural shelf. Sculpture consisting of axial ribs overridden by wide, flat¬tened, spiral cords separated by deep grooves, together forming spiral rows of axially aligned gemmules. Shell base shortly constricted to very long, sometimes recurved, siphonal canal. Aperture narrow, elongate, almost parallel-sided. Inner surface of outer lip lirate. Columella with four strong, widely spaced folds, adapicalmost the strongest. Last adult whorl with pattern of white and light-brown spiral bands, earlier spire whorls pale.

Description
Shell small, fusiform, with very long siphonal canal (w/h 0.33-0.35; a/h 0.51-0.52) and pointed apex (although almost always corroded). Protoconch conical, of -2.7 pale to orange gently convex, glossy whorls. Teleoconch of about nine whorls, suture distinct, slightly impressed. Spire whorls of nearly cylindrical profile, with distinct, though narrow, subsutural shelf and almost flat main portion of whorl. Axial sculpture of dense, closely set, axial ribs, about 28 on last adult whorl, and fine growth lines in interspaces between axials. Axial ribs overridden by wide and rounded spiral cords forming beads at intersection with axials. Early spire whorls with three, penultimate whorl with five, and last adult whorl with 12 spiral cords, separated at transition to siphonal canal by a slightly widened interspace from eight additional, low, rounded, spiral cords, rather oblique towards the tip of canal. Siphonal canal robust and very long, recurved. Aperture narrow, strongly elongate as it extends into wide siphonal canal. Outer lip slightly convex at mid-height and straight abapically, inside of outer lip with ten distinct lirae. Columella with four distinct, rather widely spaced, columellar folds, adapicalmost strongest; two adapical folds bearing shallow spiral groove on their crest, giving them a somewhat bifid profile. Background shell colour cream, last adult whorl with three distinct brown bands, one in subsu¬tural area, second just below periphery, and third at base of siphonal canal. Early spire whorls and tip of siphonal canal white. Protoconch light translucent. Radula rachiglossate, -0.9 mm long and 0.17 mm wide, consisting of about 72 rows. Rachidian with very wide bow shaped base, exceeding 40% of total radula width, tricuspidate, medial projection not pronounced, cusps equally pronounced, strong, pointed, rather short. Lateral teeth triangular, with robust base and strong, curved cusp. Etymology: The species name refers to the long, drawn siphonal canal, which distinguishes Tosapusia longirostris from other species of Tosapusia.

Our specimens display slight variations in the orientation of the siphonal canal, sculpture, and shell colour. The holotype has a distinctly recurved siphonal canal, whereas in the larger paratype the canal is coaxial. The juvenile paratype lacks coloration and seems to have more widely spaced axial ribs (19 on last adult whorl), which do not form beads at intersection with spiral cords; however, as this specimen is strongly damaged by boring Hydractinia cnidarians, which entirely covered the shell, we are inclined to attribute the observed differences to individual variation and the destructive activity of commensal Hydractinia.
Tosapusia evelynae most resembles Tosapusia longirostris. The two occur sympatrically in deep water on the Pacific side of Luzon, and can be readily distinguished by shell proportions and sculpture. Tosapusia longirostris has a stouter shell with coarser sculpture and more cylindrical whorl profile, whereas Tosapusia evelynae is more slender, with evenly convex spire whorls and more delicate sculpture.

Distribution and habitat
Solomon Islands, Philippines, depth range 278-422 m.