Tortulosa tortuosa ( Ferussac , 1821)

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

Tortulosa tortuosa ( Ferussac, 1821)

Figs 8D , 15 , 16

Turbo tortuosus - Chemnitz 1795: 158, 159, pl. 195, figs 1882, 1883. Type locality: Nicobarischen Eylanden [Nicobar Islands]. Unavailable name.

Helix (Cochlodina) tortuosa Férussac, 1821: 61.

Helix tortuosa Pupa Helix tortuosa - Gray 1825: 413.

Cyclostoma tortuosum -Sowerby I 1843: 152, pl. 28, figs 185, 186. Pfeiffer 1848: pl. 24, figs 19, 20. Pfeiffer 1849: 165, 166.

Tortulosa tortuosa -Adams and Adams 1856: 285, pl. 86, fig. 2, 2a, b. Gude 1921: 190,?Nicobars; India: Trevandrum. van Benthem Jutting 1960: 11, 12, limestone hill Kaki Bukit, near kampong Wang Tangga, Perlis [Malaysia]. Berry 1963: pl. 6, fig. 31. Hemmen and Hemmen 2001: 40, fig. 7, Wat Thum Sua, Nation Valley, near Krabi. Maassen 2001: 44. Sutcharit and Panha 2008: 50, 51, with figs, Khao Nan National Park, Nakhon Si Thammarat, Thailand. Egorov 2013: 14, 15, fig. 23. Raheem et al. 2014: 53, figs 9e, 30b, c. BEDO 2017: 98. Sutcharit et al. 2018: 159, figs 5-11f, 5-13n. Thach 2018: 97 (figure caption), figs 139, 140. Meksuwan et al. 2020: 249, fig. 2, Tonsai Waterfall, Thalang District, Phuket Province. Páll-Gergely et al. 2020: 41.

Cataulus (Tortulosa) tortuosus -Sowerby I 1866: Pupinidae , pl. 2 (pl. 264), Cataulus , fig. 1.

Cataulus tortuosus - Reeve 1878: Pupinidae , pl. 6, sp. 49. Nevill 1881: 149.

Tortulosa (Tortulosa) tortuosa - Kobelt 1902: 288, fig. 64.

Perlisia tweediei Tomlin, 1948: 225, 226, pl. 11, fig. 6. Type locality: Kaki Bukit, Perlis [Malaysia]. Páll-Gergely et al. 2020: 41, fig. 3.

Tortulosa tweediei - BEDO 2017: 98.

Tortulosa huberi Thach, 2018: 21, 22, figs 133-138. Type locality: Krabi, South Thailand. Páll-Gergely et al. 2020: 41, fig. 5.

Tortulosa schileykoi Thach & Huber in Thach, 2018: 22, figs 142-146. Type locality: Phang Nga, South Thailand. Páll-Gergely et al. 2020: 41, fig. 4.

Type material examined.

Lectotype of Perlisia tweediei NHMUK 1948.10.2.6 (Fig. 15A ) from Kaki Bukit, Perlis. Holotype of Tortulosa huberi MNHN-IM-2000-34054 (Fig. 15B ) from Krabi Province, Thailand. Holotype of Tortulosa schileykoi MNHN-IM-2000-34055 (Fig. 15C ) from Phang Nga Province, Thailand.

Material examined.

NHMUK 20100643/1-2 (2 shells) from the Nicobar Islands figured in Raheem et al. (2014: figs 30b, c). CUMZ 12154 (1 shell) from Nai-Chong Silvicultural Research Station , Mueang Krabi District, Krabi Province, 16 Jan. 2009 . CUMZ 12166 (> 500 shells; Figs 15D , 16 ) from Tham Suea Temple, Mueang Krabi District , Krabi Province, 10 May 2010 . CUMZ 12155 (12 specimens in ethanol; Fig. 8D ) from Tham Suea Temple, Mueang Krabi District , Krabi Province, 9 July 2017 . CUMZ 12156 (2 specimens in ethanol) from Phung Chang Cave , Mueang Phang Nga District, Phang Nga Province, 8 Aug. 2016 . CUMZ 12157 (1 shell) from Phung Chang Cave , Mueang Phang Nga District, Phang Nga Province, 31 July 2018 . CUMZ 12188 (2 shells) from Nam Phut Cave , Mueang Phang Nga District, Phang Nga Province, 7 Oct. 2010 . CUMZ 12158 (1 specimen in ethanol) from Ban Yai, Phanom District , Surat Thani Province, 7 Aug. 2016 . CUMZ 12159 (18 specimens in ethanol) from Khiri Rat Phatthana Temple, Wiang Sa District , Surat Thani Province, 4 July 2017 . CUMZ 12189 (3 shells) from Natural Trail, Ratchaprapha Dam, Ban Ta Khun District , Surat Thani Province, 8 Dec. 2008 . CUMZ 12160 (3 specimens in ethanol; Fig. 15E-H ) from Tham Kanlayanamit Temple, Tham Phannara District , Nakhon Si Thammarat Province, 4 July 2017 . CUMZ 12161 (3 specimens in ethanol) from Ton Din Cave , Khuan Don District, Satun Province, 7 July 2017 .

Diagnosis.

Shell rounded, spindle-shaped, translucent whitish to brown. Whorls 7, convex; third to penultimate whorls broader; last whorl narrower, detached, brought forward, with a filiform basal keel broader at the mouth. Aperture almost circular, always with basal indentation; palatal indentation obvious in specimens with thicker shell. Operculum thick cylindrical, corneous, multi-layer, spring-like when extended by force; inner operculum (attached to dorsal side of posterior body) translucent yellow, convex with crater within and conical protrusion in the middle; outer operculum (free surface) dark brown and usually eroded.

Differential diagnosis.

Tortulosa tortuosa can be distinguished from other species in this genus by a narrower last whorl that is detached from the penultimate whorl and brought forward, a shallower basal indentation, and the presence of a palatal indentation ( Raheem et al. 2014).

Distribution.

Northern Peninsular Malaysia and southern Thailand. The type locality of this species is still controversial while the occurrences in India and Nicobar Islands need further confirmation ( Sutcharit and Panha 2008; Raheem et al. 2014, 2018; Páll-Gergely et al. 2020).

Remarks.

The name Turbo tortuous Chemnitz, 1795 was published prior to Férussac’s name, but it is unavailable ( Raheem et al. 2018). See Raheem et al. (2014, 2018) and Páll-Gergely et al. (2020) for the notes on taxonomy and type specimen of this species. Currently, this is the only extant species in the subgenus Tortulosa . One extinct species, T. naggsi Raheem & Schneider, 2017 in Raheem et al. (2018) was discovered from Son La Province, Northern Vietnam. This species exhibits a terminal part of the body whorl that is fully attached to the penultimate whorl, and thus corresponds more to the subgenus Eucataulus from South Asia ( Raheem et al. 2018).

Maassen (2001) treated P. tweediei , and Páll-Gergely et al. (2020) treated both T. huberi and T. schileykoi as junior subjective synonyms of T. tortuosa . We agree on those synonymisations because the specimens we collect from the same locality exhibit a high infraspecific variation in the length of the detached part of the body whorl relative to the shell height, also in shell shape from ovate to elongate, and shell colour from translucent whitish to brown (Fig. 16 ). All the specimens in Fig. 16 were found together with hundreds of other specimens inside the same decaying log at Tham Suea Temple, Krabi Province, southern Thailand. The distribution of this species in Thailand is provided in Fig. 4 .

Figures

Figure 4. Map of southern Thailand showing the distribution of Coptocheilus sectilabris (filled square), Coptocheilus sumatranus (open square), Rhaphaulus lorraini (filled star), Rhaphaulus ascendens (open star), Rhaphaulus perakensis (asterisk), and Tortulosa tortuosa (circle). Each red symbol indicates the type locality of its respective taxon. Red circles indicate the type localities of Tortulosa huberi (1) and Tortulosa schileykoi (2).

Figure 8. Live specimens of A, B Pollicaria mouhoti mouhoti: specimens A CUMZ 12166 and B CUMZ 12175 from Wang Daeng Cave, Phitsanulok C Pollicaria mouhoti monochroma, paratype CUMZ 1562 from Tam Pha Bing Temple, Loei D Tortulosa tortuosa, specimen CUMZ 12155 from Tham Suea Temple, Krabi E-H Pupina artata: specimens of E CUMZ 12006 from Pha Daeng Cave, Mae Hong Son F CUMZ 12008 from Tham Nam Pha Pha Ngam Temple, Lampang, and G, H CUMZ 12029 from Khao Tham Raet Temple, Chachoengsao showing the brown (G) and grey (H) shell morphs; All not to scale.

Figure 15. Tortulosa tortuosa A lectotype of Perlisia tweediei NHMUK 1948.10.2.6 from Kaki Bukit, Perlis B holotype of Tortulosa huberi MNHN-IM- 2000 - 34054 from Krabi C holotype of Tortulosa schileykoi MNHN-IM- 2000 - 34055 from Phang Nga D specimen CUMZ 12166 from Tham Suea Temple, Krabi, and E-H operculum of specimen CUMZ 12160 from Tham Kanlayanamit Temple, Nakhon Si Thammarat, showing E outer operculum F inner operculum G side view (inner surface up), and H spring-like inner operculum when extended by force. Photo: M. Caballer, MNHM (B, C).

Figure 16. Infraspecific variation of shell shape and colour found in the same collecting locality of Tortulosa tortuosa, CUMZ 12166 from Tham Suea Temple, Krabi.