Cyclophorus paracucphuongensis K. C. M. von Oheimb, 2019

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 : 26

Cyclophorus paracucphuongensis K. C. M. von Oheimb , sp. nov.

urn:lsid:zoobank.org:act:803C12C9-D401-49C7-835E-3922EF9873B4

Etymology. The name refers to C. cucphuongensis , which is morphologically similar to this species.

Conchological description. Medium-sized Cyclophorus species, overall shell shape rounded, aperture typically circular. Shell height 24.4 to 26.7 mm (mean = 25.8 mm), shell breadth 28.2 to 30.9 mm (mean = 29.8 mm). Number of whorls 5 to 5.25. Early whorls without bluish colouration. Shape of body whorl uncompressed; rounded or sub-angular. Lip reflected and simple. Lip colour yellow or ivory. Wing-shaped projection at columellar margin absent, present and not pronounced, or present and pronounced. Peripheral band 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. Typical elements of pattern below position of peripheral band: spiral bands and spiral lines in darker shades of brown.

Type specimens. VNM069 ( Fig 10a ; holotype), specimen in ethanol; NHMUK 20180432; GenBank accession numbers MN153337 (COI), MN153386 (16S), MN153433 (28S); male individual; shell height 25.6 mm, shell breadth 28.6 mm, number of whorls 5.25. VNM071 ( Fig 10b ; paratype), specimen in ethanol; NHMUK 20180433; GenBank accession numbers MN153339 (COI), MN153388 (16S), MN153435 (28S); male individual; shell height 26.4 mm, shell breadth 30.3 mm, number of whorls approx. 5 (pieces of first whorl missing). VNM070 ( Fig 10c ; paratype), specimen in ethanol; NHMUK 20180434; GenBank accession numbers MN153338 (COI), MN153387 (16S), MN153434 (28S); female individual; shell height 26.1 mm, shell breadth 30.9 mm, number of whorls 5.25.

Locality and sampling data. VNM069, VNM071, VNM070: Vietnam, Thanh Hoa, Cuc Phuong National Park (20.35583˚, 105.51088˚); 02 May 2009; leg. Hao Van Luong.

Diagnosis. Cyclophorus paracucphuongensis sp. nov. 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: 38:A, 485:C (numbers indicate the position in the studied COI fragment).

Remarks. The studied material of C. paracucphuongensis has been found in western Cuc Phuong National Park in northern Thanh Hoa province ( Fig 4 ). None of the other herein characterised species is known to occur sympatrically with this species. Cyclophorus takumisaitoi occurs in northwestern Cuc Phuong National Park. The shell shape of C. takumisaitoi is similar to that of C. paracucphuongensis ( Fig 2 ). The shell of C. takumisaitoi is slightly smaller than that of C. paracucphuongensis ( Fig 3a ). The lip of C. takumisaitoi tends to have a more reddish colour than that of C. paracucphuongensis , which tends to be more yellowish. The shell colouration of C. takumisaitoi is more uniform with a less prominent peripheral band. Furthermore, C. cucphuongensis occurs in central and eastern Cuc Phuong National Park. The shell shape of C. cucphuongensis is similar to that of C. paracucphuongensis ( Fig 2 ). The shell of C. cucphuongensis is of similar size as that of C. paracucphuongensis ( Fig 3a ). On the basis of currently available shell morphological data, these two species cannot be differentiated.

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 10. Specimens of Cyclophorus paracucphuongensis Oheimb, sp. nov. Front, top and bottom view of (a) VNM069 (holotype), (b) VNM071 (paratype) and (c) VNM070 (paratype). Scale bar: 10 mm. https://doi.org/10.1371/journal.pone.0222163.g010