Anceyoconcha S. Tumpeesuwan & C. Tumpeesuwan, 2020

Sutcharit, Chirasak, Thach, Phanara, Chhuoy, Samol, Ngor, Peng Bun, Jeratthitikul, Ekgachai, Siriwut, Warut, Srisonchai, Ruttapon, Ng, Ting Hui, Pholyotha, Arthit, Jirapatrasilp, Parin & Panha, Somsak, 2020, Annotated checklist of the land snail fauna from southern Cambodia (Mollusca, Gastropoda), ZooKeys 948, pp. 1-46 : 1

Anceyoconcha S. Tumpeesuwan & C. Tumpeesuwan, 2020

Ganesella (Giardia) Ancey, 1907: 195, 203 ( Mollusca: Eupulmonata : Camaenidae ). Preoccupied by Künstler, 1882: (Metamonada: Diplomonadida : Hexamitidae ).

Pseudobuliminus (Giardia) : Zilch 1960: 639.

Pseudobuliminus (Girardius) Richardson, 1983: 94. [incorrect subsequent spelling]

Giardia : Schileyko 2003: 1519, fig. 1930. Wood and Gallichan 2008: 48.

Anceyoconcha Tumpeesuwan & Tumpeesuwan in Nahok et al., 2020: 81. New replacement name.

Remarks.

The distinguished shell character of this genus is sinistral, elongate cylindrical to more or less conical, with 6-10 convex whorls. The last whorl is rounded (not keeled), with the aperture ovate to slightly trapezoid and the apertural lip expanded. The columella is vertical, with the umbilicus narrowly opened.

Ancey (1907) established Giardia as the subgenus of Ganesella Blanford, 1863 to include two Indochinese sinistral species: Bulimus siamensis Redfield, 1853 and Bulimus rhombostomus Pfeiffer, 1861. Subsequently, this nominal name was used as a subgeneric level of Buliminopsis Heude, 1890 (family Fruticicolidae ) by Thiele (1931: 693). Zilch (1960: 639) transferred this nominal name to the Bradybaenidae as the subgenus of Pseudobuliminus Gredler, 1886, and also designated Bulimus siamensis Redfield, 1853 as the type species. Zilch’s classification was subsequently accepted and used by later authors ( Richardson 1983, Vaught 1989). Recently, Giardia was treated as a valid genus under the Camaenidae ( Schileyko 2003, 2011, Inkhavilay et al. 2019). However, the name Giardia Ancey, 1907 is a junior homonym being preoccupied by Giardia Künstler, 1882, a genus of anaerobic flagellated protozoan (Phylum Metamonada).

While cataloguing the land snail family Bradybaenidae , Richardson (1983) erroneously introduced the name " Girardius ", accompanied by diagnostic characters and attributed Bulimus siamensis Redfield, 1853 as the type species. However, this name is considered incorrect subsequent spelling ( Schileyko 2003) and thus is not available ( ICZN 1999: Art. 33.3). Nahok et al. (2020) thus proposed Anceyoconcha S. Tumpeesuwan & C. Tumpeesuwan, 2020 as a new name to replace Giardia Ancey, 1907, and included two species, A. siamensis and A. rhombostoma .

Anceyoconcha comprises around 15 nominal species and/or subspecies but there is an urgent need to clarify the boundary of this genus. Species and subspecies included in the genus as defined herein are: A. chaudoensis (Rochebrune, 1881) comb. nov., A. maestratii (Thach, 2017) comb. nov., A. mantongensis (Kobelt, 1899) comb. nov., A. obesa (Thach & Huber, 2018) comb. nov., A. ovoideus (Thach & Huber, 2018) comb. nov., A. pharangensis (Dautzenberg & H. Fischer, 1905) comb. nov., A. rhombostoma pupoidea (Dautzenberg & Fischer, 1905) comb. nov., A. rhombostoma rhombostoma , A. siamensis maxima (Ancey, 1888) comb. nov., A. siamensis nobilis (Ancey, 1888) comb. nov., A. siamensis obesula (Ancey, 1888) comb. nov., A. siamensis pervariabilis (Dohrn, 1863) comb. nov., A. siamensis siamensis , A. siamensis zonifera (Ancey, 1888) comb. nov. and A. vignei (Rochebrune, 1882) comb. nov.

The distribution of Anceyoconcha is probably within the Indochinese region of Cambodia, Laos, Thailand, and Vietnam ( Schileyko 2011, Thach 2017, 2018, Inkhavilay et al. 2019, Nahok et al. 2020).