Everettia lapidini, Liew & Schilthuizen & Vermeulen, 2009

Liew, Thor-Seng, Schilthuizen, Menno & Vermeulen, Jaap Jan, 2009, Systematic revision of the genus Everettia Godwin-Austen, 1891 (Mollusca: Gastropoda: Dyakiidae) in Sabah, northern Borneo, Zoological Journal of the Linnean Society 157 (3), pp. 515-550 : 536

publication ID	https://doi.org/ 10.1111/j.1096-3642.2009.00526.x
DOI	https://doi.org/10.5281/zenodo.5492191
persistent identifier	https://treatment.plazi.org/id/03F9878A-FF9A-E816-0D06-8D2227A8FB8C
treatment provided by	Felipe
scientific name	Everettia lapidini
status	sp. nov.

Treatment

EVERETTIA LAPIDINI View in CoL SP. NOV.

Everettia subconsul, Laidlaw, 1937: 180 View in CoL .

Types: MALAYSIA: State of Sabah: Ranau District. Southern part of Kinabalu Park. At 1900 m alt. Mesilau Resort (6°2 ′ N, 116°35 ′ E). Collected by Martinah , David , and Safrie. Date: 11.v.2007, holotype, SP 12914, Figure 6A View Figure 6 ; two paratypes, one in BMNH 20080636 and one in BOR/MOL 5500 GoogleMaps .

Etymology: This species is named after Johny Lapidin, a staff member at Kinabalu Park, who dedicatedly assisted the first author during the intensive malacological survey on Mount Kinabalu in 2005.

Material examined: SABAH – Mount Kinabalu: BOR/ MOL 973, southern slope, 1800 m alt., i.2001; BOR/ MOL 5320, southern slope, 2244 m alt., iv.2005; BOR/MOL 5321, southern slope, 2040 m alt., iv.2005; BOR/MOL 5265, southern slope, 1950 m alt., ix 2003; SP 12121, southern slope, Kiau view trail, ii.2002; SP12460, southern slope, 1900 m alt., iii.2005; SP 12500, eastern slope, Mansaranam, Kg. Pahu, v.2005; SP12916, southern slope, 1900 m alt., v.2007; SP12924, southern slope, Marai-parai, v.2007; SP 13019, southern slope, 1800 m alt., iii.2008; SP12924, southern slope, Marai-parai, v.2007; BMNH 20080202, southern slope, 1600 m alt., viii.1967; BMNH 20080203, southern slope, 2000 m alt., viii.1967. Mount Trusmadi: BOR/MOL 1293, Waras cave, 1600 m alt., iii.2002.

Diagnostic characteristics: The shell shape of this species is similar to Everettia klemmantanica , but the spiral striation above the shell characterizes this species, compared with the granule-like sculpture in E. klemmantanica .

Description: Shell ( Figs 6A View Figure 6 , 11C View Figure 11 ): large, rather thin, yellowish brown. Spire moderately elevated, outer whorls shouldered below the suture. Periphery slightly shouldered to almost rounded, more distinctly angular in juveniles. Above the periphery, shell shiny with very weak (but distinct) oblique wrinkling, slightly stronger towards the suture and with densely, regularly placed spiral grooves, c. 7–8 per mm. Below the periphery, shell has fine, densely placed spiral grooves. Height up to 16.6 mm; width up to 29.0 mm; diameter of the first three whorls 1.4–1.5, 1.0–1.1, and 2.0– 2.1 mm, respectively; number of whorls up to five and a half; height aperture up to 12.1 mm; width aperture up to 16.0 mm. Genitalia ( Fig. 7B View Figure 7 ): maximum length from genital opening to the end of dart-sac (before the visible gland tubules) up to 19 mm. The penis, dart-sac, and vagina with thick muscular walls. P, V arranged near the GO then followed by BC and DS where there is much space in the atrium between the openings of P + V and BC + DS. BC about two-thirds of total DS length. Animal ( Fig. 8J View Figure 8 ): the whole animal head is uniformly black. The mantle is black and covered by sparsely distributed tiny bright spots and followed by regularly spaced radial black bands at the last half whorl.

Distribution and habitat: Montane primary forest, from 1400 to 2000 m alt. Sabah: Mount Trusmadi, Mount Kinabalu ( Fig. 5C View Figure 5 ).

Remarks: Spiral striation on the shell is the key character for this species. The animals usually have a uniform black head, but there is a rare case where a white stripe is present between the tentacles, which is similar to the pattern in E. klemmantanica . Some immature specimens have only a few spiral striations above the shell near the periphery, and are distinctly shouldered at the periphery. We believe that this species was first collected in 1929 on Mount Kinabalu (1600 m; Pendlebury & Chasen, 1932) and Laidlaw (1937) mentioned that the shells were ‘definitely shouldered at the periphery, and like other Kinabalu specimens seem to me to differ from the type of subconsul in the British Museum’.