Shell broadly claviform (b/1 0.53-0.57; a/1 0.41-0.44) with a moderately high orthoconoid spire and a short, contracted and quite strongly tapering base. Protoconch papilliform of about 1,5 smooth whorls. Maximum protoconch diameter 0.57 mm. Teleoconch of up to about five whorls with deeply impressed, strongly wavy suture. Whorls strongly convex with an angled periphery just below mid-whorl height on earlier whorls, at middle on last two whorls. Subsutural ramp narrow, shallowly concave. Axial sculpture of strong, slightly arcuate and weakly opisthocline folds, extending from suture to suture, slightly weakening on subsutural ramp and extending on base but not on rostrum. Axial ribs of rounded triangular cross-section, interspaces concave, slightly broader to about the same width as ribs. There are nine axial folds on last two teleoconch whorls. Spiral sculpture commencing with a peripheral cord forming shoulder angle, joined on second whorl by a closely-spaced weaker cord below periphery, and a third cord near abapical suture on last two whorls; in the paratype of fourth rather weak spiral cord in the interspace between the two adapical cords and cord bordering abapical suture. Last whorl has three spiral threads on base and five threads on rostrum. Aperture oval, with a distinct, narrow, proportionally long (for genus) siphonal canal. Inner lip has a relatively thick callus forming a weak parietal tubercle. Fasciole is strong; a shallow but distinct false umbilicus is present. Outer lip has with heavy varicoid-rib behind thin lip edge. Anal sinus shallow but distinct. Shell pale buff colored. Dimensions: Holotype: 5.8 x 3.1 mm, aperture height 2.4 mm. Paratype: 4.9 x 2.8 mm, aperture height 2.2 mm.

Horaiclavus ordinei sp. nov. is a rather peculiar species morphologically and is characterized by its small dimensions, relatively low spire, strong fasciole, relatively long siphonal canal and presence of few but distinct spiral cords. The southwestern Pacific species Horaiclavus phaeocercus Sysoev in Fedosov & Kantor, 2008 and H anaimus Sysoev in Fedosov & Kantor, 2008 are superficially similar to the new species in proportions but attain a larger size (up to about 6 mm in length vs ca. 12 mm) and lack spiral sculpture on spire whorls. Among Horaiclavus species, H multicostatus (Schepman, 1913) from Indonesia has a distinct spiral cord forming a peripheral angulation on spire whorls, but otherwise spiral sculpture in restricted to base and rostrum. Shuto proposed the monotypic subgenus Anguloclavus Shuto, 1983 for H multicostatus (Schepman, 1913) but the status of this latter taxon, as well as of the two species here described, will remain uncertain until anatomical and/or molecular features become known.

Balicasag Island, Philippines trawled by local fishermen at about 200 m.