Taxonomic revision of Aegistasubchinensis (Möllendorff, 1884) (Stylommatophora, Bradybaenidae) and a description of a new species of Aegista from eastern Taiwan based on multilocus phylogeny and comparative morphology

Chih-Wei Huang; Yen-Chen Lee; Si-Min Lin; Wen-Lung Wu

doi:10.3897/zookeys.445.7778

Taxonomic revision of Aegistasubchinensis (Möllendorff, 1884) (Stylommatophora, Bradybaenidae) and a description of a new species of Aegista from eastern Taiwan based on multilocus phylogeny and comparative morphology

Zookeys. 2014 Oct 13:(445):31-55. doi: 10.3897/zookeys.445.7778. eCollection 2014.

Authors

Chih-Wei Huang¹, Yen-Chen Lee², Si-Min Lin¹, Wen-Lung Wu²

Affiliations

¹ Department of Life Science, National Taiwan Normal University, 88 Ting-Chow Rd, Sec 4, Taipei, 11677 Taiwan.
² Biodiversity Research Center, Academia Sinica, 128 Academia Road Sec. 2, Nankang Taipei 11529 Taiwan.

Abstract

Aegistasubchinensis (Möllendorff, 1884) is a widely distributed land snail species with morphological variation and endemic to Taiwan. Three genetic markers (partial sequence of the mitochondrial cytochrome c oxidase subunit I [COI], the 16S rDNA and the nuclear internal transcribed spacer 2 [ITS2]) were analysed to infer phylogenetic relationships and genetic divergence of closely related species of the genus Aegista, Aegistavermis (Reeve, 1852) and Aegistaoculus (Pfeiffer, 1850). A new species from Aegistasubchinensis has been recognized on the basis of phylogenetic and morphological evidences. The nominal new species, Aegistadiversifamilia sp. n. is distinguished from Aegistasubchinensis (Möllendorff, 1884) by its larger shell size, aperture and apex angle; wider umbilicus and flatter shell shape. The northernmost distribution of Aegistadiversifamilia sp. n. is limited by the Lanyang River, which is presumed to mark the geographic barrier between Aegistadiversifamilia sp. n. and Aegistasubchinensis.

Keywords: Helicoidea; Southern Ryukyu Islands; Stylommatophora; Yaeyama Islands; new species.