Boysidia (Boysidia) xianfengensis, Zhang & Chen & Zhou, 2014

Zhang, Wei-Hong, Chen, De-Niu & Zhou, Wei-Chuan, 2014, Two new species of the genus Boysidia from China, with a preliminary discussion of its geography (Pulmonata: Stylommatophora: Pupillidae), Zoological Systematics 39 (4), pp. 570-575 : 572-573

4.1 Boysidia (Boysidia) xianfengensis sp. nov. ( Figs 1 ― 5 )

Holotype ( IZCAS TM 136804 ), collected from Chengguan (29°06 ʹ N, 109°01 ʹ E), Xianfeng, Hubei, China, 15 August 1985.

© Zoological Systematics, 39(4): 570–575

Paratypes, 43 specimens ( IZCAS TM 136789 ― 136803 , 136805 ― 136832 ) (20 adult shells measured), collected from Chengguan , Xianfeng (29°06 ʹ N, 109°01 ʹ E), Hubei, China, 15 August 1985 .

Etymology. The name of the new species refers the type locality of the new species, Xianfeng County.

Size. Shell height 4.85 ― 4.95mm (4.91 ± 0.13 mm), shell diameter 3.00 ― 3.15 mm (3.09 ± 0.16 mm), height of aperture 1.40 ― 1.48 mm (1.43 ± 0.07 mm), diameter of aperture 1.37 ― 1.45 mm (1.41 ± 0.06 mm). Holotype. Shell height 4.90 mm, shell diameter 3.10 mm, height of aperture 1.45 mm, diameter of aperture 1.40 mm.

Description. Shell small, slightly thick, lustrous, elongated, conic. Whorls 7.5, moderately convex with high spire. Shell height about 1.57 ― 1.61 times of width. Body whorl chestnut-brown in color, becoming yellowish brown gradually towards apex. Body whorl with oblique, thick and dense growth lines, especially distinct near the aperture, becoming weakened and sparse to the penultimate and the third last whorl, the remaining whorls smooth, without growth lines. Aperture elliptical, bell-formed, slightly oblique to the left. Peristome thick, slightly expanded and reflexed, separated from body whorl. Apex blunt. Sutures well impressed. Apertural teeth numbered five: angular and parietal lamellae united into one large elevated flake-shaped tooth (Par) reaching to the apertural margin; one long flake-formed columellar tooth (Col) reaching to the apertural margin; one small nipple-shaped upper palatal tooth (Upal) nearly on the apertural edge; one large moderately elevated oblique flake-shaped lower palatal tooth (Lpal) and one small infrapalatal tooth (Ipal) deep within the aperture. Umbilicus open, deep, cavity-shaped, but not showing previous whorl.

Habitat. The new species were found in dark and moist limestone locality with bryophyte and lichen, preferring to habit on the surface of limestone, or in chink of rock, under deadwood and fallen leaves.

Remarks. The new species is similar to Boysidia (Boysidia) pentadens Chen & Wu, 1999 , but differs clearly by the shell characteristics. Shell of B. xianfengensis sp. nov. (height 4.90 mm, diameter 3.10mm, 7 1 whorls) is larger than that 2

of B. pentadens (height 3.40 mm, diameter 2.10 mm, 5 1 whorls). Five apertural teeth are bearing in both species. In B. 2

pentadens , one large nipple-formed parietal lamella, one large columellar tooth, one punctiform upper palatal tooth, one large lower palatal tooth and one small basal tooth are present, while instead of the basal tooth with a small infrapalatal tooth in B. xianfengensis sp. nov. Moreover, the umbilicus is small in B. pentadens , but open in B. xianfengensis sp. nov.

Additionally, Boysidia (Boysidia) hangchowensis (Pilsbry & Hirase, 1908) and B. (B.) hunana (Gredler, 1881) ( Heude, 1882 ― 1885) also have 5 apertural barriers, but have columellar teeth downwardly curved, rather than straight in B. xianfengensis sp. nov. and B. pentadens .

Figures

Figs 1–5. Boysidia (Boysidia) xianfengensis sp. nov. 1. Apertural view. 2. Right-lateral view. 3. Left-lateral view. 4. Umbilical view. 5. Aperture enlarged. Scale bars: 1―4=1 mm, 5=0.5 mm. Abbreviations: Par =parietal tooth; Col=columellar tooth; UPal=upper palatal tooth; LPal =lower palatal tooth; IPal=infrapalatal tooth.