Bakyietaia jingweiae Yen, Zhang & von Rintelen, 2025

Bakyietaia jingweiae Yen, Zhang & von Rintelen gen. et sp. nov.

urn:lsid:zoobank.org:act:

Figs 22–23 View Fig View Fig

Diagnosis

Shell small to medium in size (26.79 ± 5.37 mm), sturdy, conical, whorls not inflated, prominent keel above suture; columellar lip recurved, forming callus covering umbilicus completely; operculum with small nuclear region (around 1/4 of inner opercular region) with shiny grains or veins; outer marginal tooth of radula with 26–28 small sharp cusps; distributed in northernVietnam, across the border in western Guangxi and in western Hainan Island, China.

Etymology

Named after ‘Jingwei’, a Chinese mythical bird into which the Flame Emperor Yandi’s daughter Nüwa, who drowned in the sea, was transformed, and which tried to fill up the sea. The recommended Chinese name is DZIṉ田ª.

Material examined

Holotype

CHINA • spec. preserved in ethanol; Guangxi, Baise City, Jingxi County, Xinjing Town , Longtan Wetland , 0.1 m on rock; 30 Dec. 2019; Hua-Pu Huang leg.; KIZ.240006 .

Paratypes

CHINA – Guangxi • 4 specs (preserved in ethanol); same data as for holotype; KIZ.240056 to KIZ.240059 • 5 specs.(preserved in ethanol); same data as for holotype; ZMB.122701 • 1 spec. (preserved in ethanol); Guangxi, Baise City, creek near Nawang Village , 0.1 m deep on sand or rock substrate; 20 Mar. 2022; Le-Jia Zhang leg.; KIZ.240007 . – Hainan Province • 3 specs (preserved in ethanol); Ledong Li Autonomous County, Honghu Village, Honghu Lake , 0.1 m deep sand substrate; 9 Mar. 2022; Le-Jia Zhang leg.; ZMB.122737-1 , ZMB.122737-2 , ZMB.122737-4 • 1 spec. (preserved in ethanol); Changjiang Li Autonomous County, Changhua Town, Sanjia Village , Changhua River , 0.5 m deep on rock; 9 Mar. 2022; Le-Jia Zhang leg.; KIZ.240008 .

VIETNAM • 4 specs (preserved in ethanol); Cao Bang, river Sông Bằng ; 2000; IEBR leg.; MZMB.114431 • 3 specs (preserved in ethanol); Ca River drainage, Ho-Chi-Minh-Highway between Yen Cat and Thái Hòa, Nghê An; 21–31 Oct. 2006; Frank Köhler leg.; ZMB.114407 • 2 specs (preserved in ethanol); Ba Be Lakes , Bac Kan; 2001; IEBR leg.; ZMB.114430 • 10 specs (preserved in ethanol); Ba Be Lakes , Bac Kan, ferry port; 21 Mar. 2006; Frank Köhler leg.; ZMB.114189 .

Other material

CHINA • 3 specs (preserved dry); same data as for holotype; YHY-BAKDUC-JX-1 , YHY-BAKDUC-JX-10 , YHY-BAKDUC-JX-15 .

Description

Adult shell ( Fig. 22A–N View Fig ) small to medium (26.79 ± 5.37 mm), thin to thick, sturdy, conical, olive to olive brown, with five to six whorls, apex acute; teleoconch whorls slightly inflated, with three smooth primary keels, with one to two weaker smooth secondary keels located between suture and first keel, sometimes one additional weak keel located between first and second/second and third keels, base of shell with one to three weak keels, all keels usually darker than rest of shell surface; aperture ovate, less than half of shell in height, inner shell surface bluish white, outer lip thin, always with a strong angular periphery, columellar lip covered with thick inner shell layers, white or orange-red, adult columellar lip recurved, sometimes forming a narrow to wide crescent-shaped callus, this structure or columellar lip completely covering umbilicus.

Operculum ( Fig. 22O–P View Fig ) corneous, ovate, relatively thick, dark red; exterior surface smooth; interior surface with small nuclear region, around 1/4 of inner opercular region, with shiny grains or veins or smooth glossy surface.

Radular ( Fig. 23 View Fig ) (n = 4) central tooth with one broad central denticle and four to six small sharp cusps on either side; lateral tooth with one broad central denticle and five to six small sharp cusps on either side; inner marginal tooth narrow, about half of lateral tooth in width, with one broad central denticle and four to five small sharp cusps on either side; outer marginal tooth wide, almost same width as lateral tooth, with 26 to 28 small sharp cusps.

Remarks

Bakyietaia jingweiae gen. et sp. nov. is most similar to Bakyietaia boettgeri based on shell morphology, but differs in possessing a smaller shell and greater number of small cusps on outer marginal teeth (26–28 vs 23–24). The distribution areas of these two species are close to each other but not overlapping near the border between Guangxi, China and Vietnam.

Habitat and distribution

Sand substrate and rocks in the shallow water of rivers and lakes of western Guangxi and western Hainan Province, China and northern Vietnam.