Original Description of Anchura halberdopsis by Elder & Saul, 1996:
- "Shell medium-sized, high-spired, pleural angle about 30 degrees, drawn out anteriorly into anterior rostrum; whorl gently, unevenly rounded becoming slightly angulate on penultimate whorl and strongly angulate on last whorl; whorls about eight in number; suture appressed; protoconch unknown; varices randomly present on juvenile and adolescent whorls; growth line antispirally concave on spire. Mature sculpture strong, of both axial ribs and spiral cords; axial ribs nearly straight on spire, strongest on early whorls, weakening on body whorl, 11-13 on penultimate whorl, forming nodes where crossed by spiral cords, strong nodes developed on angulation of last whorl; spiral cords stronger on penultimate and ultimate whorls, four to five cords showing on spire whorls, fourth cord strongest, forming a noded keel on ultimate whorl and extending onto shank as carina; six to seven cords anterior of keel on ultimate whorl, third cord usually strongest; juvenile sculpture of closely spaced arcuate axial ribs on at least two whorls. Outer lip expanded into ax-shaped wing, anterior margin angulate (near 90 degrees) at posteriorward bend, thickened internally and filled with callus; posterior end of wing tilted near 15 degrees abaperturely to axis of spire. Aperture with moderately thick, broad inner lip extending apically almost to previous suture. Thick, sinuous, elongate callus pad formed on base along inner lip edge"
Locus typicus: CIT (California Institute of Technology) loc. 1053, northeast-southwest trending spur north of Santiago Creek, 200' N, 2850' E of SW corner sec. 20, T5N, R 7W, El Toro quadrangle, Santa Ana Mountains, Orange County, California, USA.
Stratum typicum: Turritella chicoensis holzana Zone; associated with Submortoniceras chicoense (Trask) early Campanian, Cretaceous
Distribution: Santa Ana Mountains, Orange County, California in the upper part of the Holz Shale Member of the Ladd Formation.
Type specimens: Holotype, LACMIP no. 11305 (Natural History Museum of Los Angeles County, Invertebrate Paleontology); Paratypes LACMIP no. 11306 to 11311 all from California Institute of Technology (CIT) loc. 1053.
Etymology: English, halberd, a shafted weapon with an ax-like cutting blade + Greek, opsis, having the aspect of.