Original description of Drepanocheilus (Tulochilus) retisurus by Stilwell, 2003
- "Shell relatively minute for family (height of reconstructed shell about 15 mm), thin, delicate, polished in well-preserved specimens, strongly alate; spire angle approximately 45º; whorl inflation great on protoconch whorls, then slowing markedly on teleoconch spire, becoming strong again between penultimate and last whorls; growth lines opisthocyrt on adapical half of whorls, becoming more opisthocline abapically; spire moderately high to very high, of at least six uniangulate, subquadrate whorls; protoconch polygyrate, large, smooth, of 3-3½ rapidly expanding convex whorls; last whorl biangulate, with moderately strong subcentral. rubercle-bearing keel and more poorly developed peribasal keel just below carina and above onset of strong basal constriction; spire whorls with more than 15 axially elongate, strongly opisthocline, mostly evenly spaced, moderately blunt tubercles and inclined riblets; spiral sculpture variably weak, of some 20 closely spaced riblets; axials slightly stronger than spirals, and where crossing, create a weakly reticulate pattern of poorly developed pustules, most developed on first teleoconch whorl; more than 25 primary spirals on last whorl with weak interstitial lines; spirals diverge on wing and become deflected adapically; tubercles end at beginning of wing; wing strongly developed with adapically projecting, moderately concave and strongly upturned and deflected spike; wing with moderately strong spirals; inner surface of wing with deep primary groove following length of spike; neck reduced to small spike; aperture elongate, sublenticular to ovate, with narrow notch; inner lip details not known, but if callus present may not extend greatly."
Locus typicus: Otway National Park, Victoria, Australia
Stratum typicum: late Paleocene – earliest Eocene
Etymology: Species named for its reticulate sculptural configuration and southern occurrence.
Reference: J.D. Stilwell, 2003