Type material: Holotype (57.4mm wide x 39.8mm high) deposited at National History Museum, London, UK. with Registration No: NHMUK 20230147.
Other material: Paratype 1 (53.8mm) in Dr Thach collection. Paratype from type locality.
Diagnosis: The new species is characterized by robust shell, large adult size, angulate columella, very thick outer lip, prominent and oblique ribs, red-brown band at ventral side.
Description: Shell large for the genus, thick and turbinate in shape. Spire moderately high and very narrow (only 35.5% of shell width), sutures broadly channeled. Shell height 69.3/% of holotype height. Body whorl inflated with narrow and sharp keel at periphery. Outer surface ornamented at dorsal side with some short white stripes and a red-brown band at the middle of ventral side. Sculpture consists of many oblique, elevated and widely-spaced ribs crossing more closely-spaced spiral ribs at dorsal side of body whorl; basal side with weaker ribs and fine radial grooves. Aperture oblique, subcircular in outline and occupying 71.6% of holotype height, 52% of holotype width, outer lip very thick, highly calloused and strongly reflected. Columella also highly calloused and angulate with posterior part nearly parallel to shell axis, umbilicus wide, deep and partly covered by columella. Color blackish brown with whitish apex, ivory white columella, outer lip and umbilical area. Operculum corneus, multispiral, very concave with many narrow, oblique ribs at exterior side; interiorly glossy and red.

The new species is not illustrated in the article on Cyclophorus spp. from North Vietnam of von Oheimb KCM et al. (2019) at doi.org/10.1371/journal.pone.0222163 and in the article on Cyclophoridae from Vietnam of Do & Do (2019). The new species differs mainly from Cyclophorus huberi Thach, 2016 in following characters: (1) angulate columella, (2) more elongate aperture, (3) much wider outer lip, (4) different parietal wall, (5) more angulate periphery of body whorl, (6) presence of dark brown and pink bands at ventral side, (7) oblique ribs different, (8) channeled sutures, (9) conjunction area between outer lip and columella less rounded, (10) different localities: Tay Ninh Province of South Vietnam versus Quang Nam Province of Central Vietnam. These numerous differences are sufficient to separate them into two species.
The new species is distinguished mainly from Cyclophorus stungtrengensis Thach & F.Huber, 2018 in following characters; (1) aperture oblique and turned foreward, not rightward, (2) much thicker columella and outer lip, (3) different pattern, (4) sutures deeper, (5) umbilicus partly covered by columella, (6) columella not regularly curved, (7) presence of oblique ribs at dorsal side, (8) different localities, Tay Ninh of Vietnam versus Stungstreng of Cambodia at 335km apart.

Type locality: Tan Bien District, Tay Ninh Province, South Vietnam, about 40 km far from the border of Cambodia.
Habitat: around trees.