Description. — Shell large for the genus, slender, sculpture weak. Holotype, MNHN2119, 22.4 x 7.4 mm
Protoconch (based on the holotype) swollen, multispiral, n 1.5 whorl, D 1.2 mm, d 0.3 mm, e.h. 1.0 mm. Transition to teleoconch only marked by diffuse start of teleoconch sculpture, 6 1/8 rounded teleoconch whorls, without shoulder or sutural ramp. Sutures not deeply impressed. Shell finely sculptured, varices narrow and low, their shoulder "hook" low. Spirals on spire: 13-14, on last whorl 38 narrow spiral bands, all of about the same strength. Axials on 2nd and 3rd teleoconch whorl 19; on 4th: 22; on 5th: 27; on last whorl 45 axials (27 axials between varices). Coronation very weak. Aperture elongate, narrow, with a well-marked posterior canal. Outer lip with 19 very short (0.5 mm) lirae, irregularly placed, near the outer rim of the lip. Columellar callus thin, white, continuing into a freestanding collar that partly hides the narrow umbilical slit. Columella very slightly curved near its middle, no columellar folds.
The general color of the shell is a very pale fawn, with a few narrow vertical streaks of brown from the second teleoconch whorl on, changing into broader blotches of the same brown on later whorls, the collared areas are placed in the middle between two varices. The paratype has only a few pale brown squares dots, placed near the suture next to the varices on the younger part of the whorl, the last two varices have two pale brown streaks near the periphery.
Distribution. — Indonesia, off Kai Islands, and Bohol, Philippines.
Remarks. — The protoconch of this shell is partly broken, its type cannot be established, maximum diameter was apparently 1.1 mm, but the holotype has a multispiral protoconch. This shell from PANGLAO 2004 Stn Tl 1, the second known of the species, is quite larger than the holotype. Its axial sculpture (30 on last whorl) is slightly finer than in the holotype (26).
There is a strong resemblance in size, general shell form and color, between this species and T. siphonata (Reeve, 1844) from off Baja California to Ecuador (Beu & Maxwell, 1987: 46) which also has a multispiral protoconch. This resemblance is surprising in view of the huge distance between both geographic areas, separated by the "East Pacific Filter Bridge" and the whole central Pacific.
With its elongated form and rather weak sculpture, T. beui resembles T. indoceana Beu & Maxwell, 1987, from off Mozambique, but it lacks the 10-12 microscopic lirae between the spiral bands (but see remark under Tritonoharpa), and its spirals get higher when they cross the axials instead of becoming lower as in T. indoceana.

Type locality: Off Kai Island, Karubar stn. DW30, 111-118 m.
Distribution: Southern Moluccas, Indonesia; Bohol, Philippines; now also Red Sea.