Coptocheilus sectilabris (Gould, 1843)

Jirapatrasilp, Parin, Sutcharit, Chirasak & Panha, Somsak, 2022, Annotated checklist of the operculated land snails from Thailand (Mollusca, Gastropoda, Caenogastropoda): the family Pupinidae, with descriptions of several new species and subspecies, and notes on classification of Pupina Vignard, 1829 and Pupinella Gray, 1850 from mainland Southeast Asia, ZooKeys 1119, pp. 1-115 : 1

Coptocheilus sectilabris (Gould, 1843)

Fig. 5A-C

Cyclostoma sectilabrum Gould, 1843: 140. Type locality: Tavoy [Dawei, Dawei Township, Dawei District, Tanintharyi Region, Myanmar]. Gould 1844: 459, pl. 24, fig. 10. Pfeiffer 1848: pl. 24, figs 17, 18. Pfeiffer 1849: 164, 165. Johnson 1964: 147.

Megalomastoma sectilabre - Theobald 1858 [1857]: 247, Yanglaw, on the Tenasserim [Tanintharyi Region, Myanmar].

Megalomastoma sectilabrum -Sowerby I 1866: Pupinidae , pl. 1 (pl. 263), Pollicaria and Megalomastoma , sp. 19, fig. 24. Hanley and Theobald 1870: 4, pl. 7, fig. 3. Reeve 1878: Pupinidae , pl. 10, sp. 88. Crosse 1879: 339. de Morgan 1885: 412, 413.

Megalomastoma (Coptocheilus) sectilabrum - Nevill 1878: 297.

Megalomastoma (Coptochilus) sectilabrum - von Martens 1886: 161, King Island [Kadan Island or Kadan Kyun, Kyunsu Township, Myeik District, Tanintharyi Region, Myanmar]. von Möllendorff 1887 [1886]: 314, Tenasserim.

Schistoloma sectilabrum - Kobelt 1902: 280. Gude 1921: 170, 171. Zilch 1957: 42. Maassen 2001: 43. Tumpeesuwan and Panha 2008: 65, 66, fig. 1a-c, Kaeng Krachan National Park, Phetchaburi Province, Thailand. Egorov 2013: 14, fig. 22d-g. BEDO 2017: 97. Sutcharit et al. 2018: 157, figs 5-11e, 5-13m. Páll-Gergely et al. 2019: 325, 326.

Type material examined.

Lectotype MCZ 169361 (Fig. 5A ) from Tavoy. Paralectotype MCZ 87934 (1 shell) from Tavoy.

Other material examined.

SMF 109813 (1 shell; Fig. 5B ) from Tavoy. CUMZ OLM-0111 (1 shell; Fig. 5C ) from Kaeng Krachan District, Phetchaburi Province, 20 Sept. 1998.

Diagnosis.

Shell elongate conical without any periumbilical keel. Aperture round with a slight angular indentation at upper junction of peristome.

Differential diagnosis.

Coptocheilus sectilabris is different from C. sumatranus in having a slight angular indentation at the upper junction of the peristome.

Distribution.

Myanmar and western Thailand ( Tumpeesuwan and Panha 2008).

Remarks.

As the original description did not explicitly state that the description of this species was based on a single specimen (nor could this be inferred), the designation of a holotype by Johnson (1964) in fact constitutes a lectotype designation ( ICZN 1999: Art. 74.6). Several records of C. sectilabris from southern Thailand and peninsular Malaysia should be recognised as C. sumatranus (see below). The occurrence of C. sectilabris in Vietnam ( Thach 2016) is dubious and needs further confirmation ( Páll-Gergely et al. 2019).

Figures

Figure 5. A-C Coptocheilus sectilabris: A lectotype MCZ 169361 from Tavoy B specimen SMF 109813 from Tavoy, and C specimen CUMZ OLM- 0111 from Kaeng Krachan, Phetchaburi D-F Coptocheilus sumatranus: D syntype of Coptocheilus perakensis NHMUK 1903.11.20.33 from Perak E specimen SMF 262529 / 1 " Schistoloma siamensis Brandt " from Thailand: an den Tanto-Faellen bei Ban Nong Star; Yala Provinz, and F specimen NHMUK 1986.4.19.14 " Coptocheilus sectilabrum var. " from Larut near Perak.