Figs. 1, 3 F, 8 E; Table 2
Type material. Holotype: HBUMM-01023–specimen 1 (fms); 5 km from Fengyi Town on the road to Wenchuan County, 1574 m a.s.l., 31 ° 39 ʹ 35.4 ʹ N, 103 ° 48 ʹ 48.7 ʹ E, Maoxian County, NW Sichuan, China, 2004 –X– 11, leg. M. Wu. Paratypes: HBUMM-01023–specimen 2 (fms), same data as holotype; HBUMM-01794–specimen 1 (broken fms), Hongqi Hill (ca. 2 km south of the town of Maoxian), Maoxian County, NW Sichuan, China, 2004 –IX, leg. M. Wu.
Type locality. 5 km from Fengyi Town on the road to Wenchuan County, Maoxian County, NW Sichuan.
Material examined. Type material.
Distribution. Sichuan (Maoxian County).
Etymology. The new species is named after the county name “ Maoxian.” The epithet is a noun in apposition.
Diagnosis. Shell with 8.125 whorls. Height 8.8–8.9, diam. maj. 2.2–3.4. Parietal tooth absent. Columellar tooth prominent and expanded inward. Palatal wall with a ridge-like tooth.
Shell. Fusiform; apex not acuminate; dextral; thin-shelled; solid; semitranslucent; glossy; with 8.125 – 8.125 – 8.125 whorls. Whorls never spirally grooved; convex. Embryonic shell smooth; polished; with 1.500–1.563 – 1.625 whorls. Postnuclear whorls wrinkled. Suture simple. Last whorl gradually ascending toward aperture; rounded at periphery. Shell 8.8 – 8.8–8.9 high; 2.2–2.8 – 3.4 in diam. maj. Height/diam. maj. ratio 2.64–3.36 – 4.08. Aperture ovate; slightly oblique; its insertions separated; 1.8–2.3 – 2.8 high, 2.0– 2.1 – 2.1 wide. Ratio of shell height to aperture height 3.17–3.97 – 4.77. Peristome expanded; sharp. Palatal margin rounded. Palatal tooth present, ridgelike, extending approximately 1.25 whorls inward. Parietal callus indistinct; with angular tubercle. Parietal tooth absent. Columellar margin reflexed; with one prominent tooth which is expanded inward. Umbilicus a narrow slit. Shell uniformly light brownish-white; aperture white.
Remarks. This new species is grouped into the genus Pupopsis because of its typical apertural armature. The unique shell contour with a pointed apex and a narrowed body whorl, and the combination of the absence of a parietal tooth and the presence of both palatal, ridge-like tooth and columellar tooth set P. m a o x i a n apart from all other species in the genus.
This new species lives in a habitat charaterised by seasonal change of aridity and wetness. The detailed environmental characters are almost the same as described in Wu et al. (2003) for Cathaica (Pliocathaica) radiata Pilsbry, 1934.