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

Cyclophorus paracucphuongensis K. C. M. von Oheimb View in CoL , 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 View Fig 10 ; 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 View Fig 10 ; 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 View Fig 10 ; 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 View 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 View Fig 2 ). The shell of C. takumisaitoi is slightly smaller than that of C. paracucphuongensis ( Fig 3a View Fig 3 ). 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 View Fig 2 ). The shell of C. cucphuongensis is of similar size as that of C. paracucphuongensis ( Fig 3a View Fig 3 ). On the basis of currently available shell morphological data, these two species cannot be differentiated.