Pyramidula 錐塔蝸牛屬
Pyramidula conica lakainguta (Hwang, 2014) 知本錐塔蝸牛
節錄自發表文獻 Abstract:
為台灣新紀錄的ㄧ科
This is the first record of the Family Pyramidulidae in Taiwan. This family is different to the members of the families Valloniidae, Punctidae, Discidae and Endodontidae due to the simple peristome and the lack of spiral striae and apertural armature (Pilsbry, 1935; Zilch,
1959-1960).
外殼形態和地理分布最接近的物種 Pyramidula conica (Pilsbry & Hirase, 1902) /日本,四國
Pyramidula conica (Pilsbry & Hirase, 1902) from Shikoku, Japan is the most morphologically
closed species among Pyramidula species (Azuma, 1995). Based on the photographs of the
lectotype ANSP 83884 (Malacology Collection at the Academy of Natural Sciences of
Philadelphia), both taxa have similar ratio of shell height/shell width around 0.7, ratio of
umbilicus width/shell width around 0.3, ratio of aperture width/ shell width, about 0.36–0.4, and
irregular striae on shell surface (Pilsbry & Hirase, 1902). However, the striae of this new
subspecies is more irregular, looser and rougher than P. conica, particularly on the last whorl.
Beside the morphological similarities, P. conica lakainguta n. subsp. is also geographically
close to P. conica s. str. Migrating birds are probably contribute to long distance transportation
of micro land snails to remote islands (Gittenberger et al., 2006; Wada et al., 2011). The two
Pyramidula are distributed in the East Asian – Australasian migratory shorebird flyway. They
may have closer phylogenetic relationship than other congeners. Because of the moderate
morphological differences and geographical isolation, I consider Taiwanese Pyramidula a new
subspecies.
