Cyclophorus subfloridus Ancey, 1888

von Oheimb, Katharina C. M., Oheimb, Parm Viktor von, Hirano, Takahiro, Do, Tu Van, Ablett, Jonathan, Luong, Hao Van, Pham, Sang Van & Naggs, Fred, 2019, Cryptic diversity of limestone karst inhabiting land snails (Cyclophorus spp.) in northern Vietnam, their evolutionary history and the description of four new species, PLoS ONE (e 0222163) 14 (10), pp. 1-37 : 22-24

Cyclophorus subfloridus Ancey, 1888 [ 92]

Conchological description. Medium-sized Cyclophorus species, overall shell shape rounded, aperture typically circular. Shell height 22.3 to 30.4 mm (mean = 26.7 mm), shell breadth 23.9 to 33.7 mm (mean = 29.6 mm) (sub-group I: shell height 25.2 to 30.4 mm

(mean = 28.2 mm), shell breadth 29.0 to 33.7 mm (mean = 31.4 mm); sub-group II: shell height 22.3 to 27.4 mm (mean = 25.2 mm), shell breadth 23.9 to 30.3 mm (mean = 27.7 mm)). Number of whorls 5 to 5.5 (sub-group I: 5.25 to 5.5; sub-group II: 5 to 5.25). Early whorls with bluish colouration. Shape of body whorl usually uncompressed; rounded or well-rounded (sub-group I: usually uncompressed; well-rounded or rounded; sub-group II: uncompressed; usually rounded). Lip reflected and simple, or unreflected and duplicated (sub-group I: reflected and simple; sub-group II: reflected and simple, or unreflected and duplicated). Lip colour ivory or white. Wing-shaped projection at columellar margin absent, present and not pronounced, or present and pronounced (sub-group I: present and not pronounced, present and pronounced, or absent; sub-group II: absent, or present and not pronounced). Peripheral band usually dark brown (sub-group I: dark brown; sub-group II: usually dark brown). Colour pattern generally variable. Typical elements of pattern above position of peripheral band: zig-zag stripes and flames in different shades of brown or in white (sub-group I: zig-zag stripes and flames in different shades of brown; sub-group II: zig-zag stripes and flames in different shades of brown or in white). Typical elements of pattern below position of peripheral band: spiral lines, spiral bands, zig-zag stripes and transverse lines in different shades of brown or in white (sub-group I: spiral lines, spiral bands and transverse lines in darker shades of brown; sub-group II: zig-zag stripes, spiral bands and spiral lines in different shades of brown or in white).

Displayed specimens. VNM063 ( Fig 8a ; sub-group I), specimen in ethanol; NHMUK 20140597 (ethanol-preserved frozen tissue sample NHMUK Barcode 014041340); GenBank accession numbers MN153334 (COI), MN153383 (16S), MN153430 (28S); female individual; shell height 27.6 mm, shell breadth 31.0 mm, number of whorls 5.25. VNM059 ( Fig 8b ; sub-group I), specimen in ethanol; NHMUK 20140557/2; GenBank accession numbers MN153330 (COI), MN153379 (16S), MN153426 (28S); male individual; shell height 28.2 mm, shell breadth 31.1 mm, number of whorls 5.25. VNM061 ( Fig 8c ; sub-group I), specimen in ethanol; NHMUK 20140585/1 (ethanol-preserved frozen tissue sample NHMUK Barcode 014041339); GenBank accession numbers MN153332 (COI), MN153381 (16S), MN153428 (28S); female individual; shell height 28.4 mm, shell breadth 31.5 mm, number of whorls 5.25. VNM065 ( Fig 8d ; sub-group II), specimen in ethanol; NHMUK 20110594 (ethanol-preserved frozen tissue samples NHMUK Barcode 014041334, NHMUK Barcode 014041351); GenBank accession numbers MN153336 (COI), MN153385 (16S), MN153432 (28S); sex of individual not determined (parts of soft body damaged); shell height 24.7 mm, shell breadth 26.8 mm, number of whorls 5.25.

Locality and sampling data. VNM063: Vietnam, Lang Son, Yen Thinh commune (21.61862˚, 106.34760˚); 19 September 2013; leg. Jonathan Ablett, Hao Van Luong, Fred Naggs & Sang Van Pham. VNM059: Vietnam, Lang Son, Huu Lien commune, Huu Lien Nature Reserve (21.66235˚–21.65998˚, 106.36633˚–106.36462˚); 17 September 2013; leg. Jonathan Ablett, Hao Van Luong, Fred Naggs & Sang Van Pham. VNM061: Vietnam, Lang Son, Yen Thinh commune (21.65948˚, 106.36535˚); 18 September 2013; leg. Jonathan Ablett, Hao Van Luong, Fred Naggs & Sang Van Pham. VNM065: Vietnam, Lang Son, Trung Quan commune (22.13137˚, 106.58715˚); 23 May 2011; leg. Hao Van Luong, Fred Naggs & Sang Van Pham.

Diagnosis. Cyclophorus subfloridus can be differentiated from all herein characterised Cyclophorus species based on DNA sequence data. Diagnostic nucleotide substitutions of the cytochrome c oxidase subunit I (COI) gene: 217:A (number indicates the position in the studied COI fragment).

Remarks. This species was originally described as Cyclophorus fulguratus var. subflorida . Despite extensive effort, we were unable to locate type material of this species (see also [ 107]). Our determination was thus based on the description and figure in Ancey [ 92]. The description and the depicted shell matched sub-group I in size, shape and colouration. The material of C. fulguratus studied in Ancey [ 92], which includes the therein newly described C. fulguratus var. subflorida (a specific type locality for this taxon is not given), is “from Lang Son to Bac Ninh” (original: “De Lang-son a Bac-Ninh”), and our studied samples of sub-group I were collected from localities in this area. We regard Cyclophorus fulguratus var. barniana Ancey, 1888 [ 92] as a synonym of this species given that the type material of both taxa was presumably collected in the same region [ 92] and that the described morphological differences between them are insignificant (note that no type material of C. fulguratus var. barniana could be located; see also [ 107]). Cyclophorus jourdyi var. longsonensis Morlet, 1891 [ 110] is regarded as a further synonym of C. subfloridus given that its type locality is “Lang Son” (original: “Long-son”) and that the studied type material (RBINS I.G.10591/MT.903, labelled as paratype, and MNHNIM-2000-34483 and MNHN-IM-2000-34484, both potential syntypes) resembled sub-group I of C. subfloridus in size, shape and colouration (only in MNHN-IM-2000-34483 the early whorls lacked a bluish colouration). We regard the material from northern Thailand, which has been determined as C. subfloridus by Nantarat et al. [ 47] (also included in the phylogenies of [ 6] and this study, herein THA025), as belonging to a different species. The studied material of C. subfloridus has been found in southwestern Lang Son province, partly in Huu Lien Nature Reserve, (sub-group I) and in northern Lang Son province (sub-group II) ( Fig 4 ). Another herein characterised species, C. courbeti (sub-group I), occurs sympatrically with C. subfloridus (sub-group II) in northern Lang Son province. The shell shape of C. courbeti is generally more compressed than that of C. subfloridus ( Fig 2 ). The shell of C. courbeti sub-group I is larger than that of C. subfloridus sub-group II ( Fig 3b ) and the early whorls lack a bluish colouration, while those of C. subfloridus sub-group II show a bluish colouration. The lip of C. courbeti sub-group I tends to have a more yellowish or reddish colour than that of C. subfloridus sub-group II, which tends to be more whitish. Furthermore, C. fasciatus (sub-group I) occurs in eastern Thai Nguyen province, approx. 20 km from where C. subfloridus (sub-group I) was found, in southwestern Lang Son province. The shell shape of C. fasciatus is generally slightly more compressed than that of C. subfloridus ( Fig 2 ). The shell of C. fasciatus sub-group I is slightly larger than that of C. subfloridus sub-group I ( Fig 3b ) and the early whorls usually lack a bluish colouration, while those of C. subfloridus sub-group I show a bluish colouration. The lip of C. fasciatus sub-group I tends to have a more yellowish or reddish colour than that of C. subfloridus sub-group I, which tends to be more whitish.

Figures

Fig 2. Canonical variate analysis (CVA) of shell shape data. The delimited Cyclophorus species are colour-coded.Data points of individuals belonging to major clade A are shown as triangles, data points of individuals belonging to major clade C are shown as circles. The figures at the axes represent the transformation from the overall mean shape at -12 and 6 (CV1), and at -6 and 6 (CV2). https://doi.org/10.1371/journal.pone.0222163.g002

Fig 3. Boxplot diagram of shell size. (a) Shell size (defined as the area of the polygon spanned by all generated semi-landmarks) of delimited Cyclophorus species and (b) of sub-groups. Boxes encompass the second and the third quartiles. Horizontal lines within each box represent the median. Top and bottom whiskers show the largest and smallest data point.

Fig 4. Sampling localities of Cyclophorus spp. in northern Vietnam. Markers with large symbols refer to sampling localities of Cyclophorus species that develop the widespread morphotype (colour-coded according to species); squares indicate that individuals of the widespread morphotype were present in the studied material from the respective localities and circles indicate that such individuals were not present. Roman numerals refer to sub-groups of individual species. The question mark indicates that the exact sampling locality is unknown (the respective marker shows the location of the market stall where the material of Cyclophorus sp. 1 was obtained). Markers with small white circles refer to localities, from where only Cyclophorus species that have not been found to develop the widespread morphotype were studied. The map shows all sampling localities of Cyclophorus specimens from Vietnam from S1 and S2 Tables, with the exception of three localities that are outside the map section (all of them only with species that have not been found to develop the widespread morphotype). Sampling localities for samples from Nantarat et al. [47] were derived from the map in their paper. The distribution of limestone karst (according to [85]) is shown in dark grey. https://doi.org/10.1371/journal.pone.0222163.g004

Fig 8. Specimens of Cyclophorus subfloridus Ancey, 1888 [92]. Front, top and bottom view of (a) VNM063 (subgroup I), (b) VNM059 (sub-group I), (c) VNM061 (sub-group I) and (d) VNM065 (sub-group II). Scale bar: 10 mm. https://doi.org/10.1371/journal.pone.0222163.g008