Indoartemon prestoni ( Gude, 1903 )

Siriboon, Thanit, Sutcharit, Chirasak, Naggs, Fred, Rowson, Ben & Panha, Somsak, 2014, Revision of the carnivorous snail genus Indoartemon Forcart, 1946 and a new genus Carinartemis from Thailand (Pulmonata: Streptaxidae), Raffles Bulletin of Zoology 62, pp. 161-174 : 163-164

Indoartemon prestoni ( Gude, 1903)

( Figs. 1 , 3C, D , Table 1)

Streptaxis prestoni Gude, 1903: 322 , 323, pl. 12, figs 17–19. Type locality: Lampun , Siam.

Haploptychius prestoni: Kobelt, 1906: 140 , 141, pl. 62, figs 16–18. Zilch, 1961: 84. Richardson, 1988: 219.

Oophana (Indoartemon) prestoni: Benthem Jutting, 1954: 96 .

Material examined. Of the two specimens mentioned by Gude (1903: 323) the single syntype in the lot NHMUK 1922.8 .29.5 ( Fig. 3C ) is here designated as the lectotype. Additional record: CUMZ 5015 (12 shells; Fig. 3D ), Wat Tam Ra-Khang , Si Samrong, Sukhothai, northern central lowlands, Thailand. Isolated limestone hills reaching about 200 m above mean sea level (17°9.6'6.0"N, 99°33'35.7"E) .

Indoartemon prestoni can be distinguished from I. laevis from Myanmar by its higher spire and distinct suture, regularly expanding whorls, deeper umbilicus and presence of a basal lamella. This species differs from I. cingalensis in its larger shell, lower spire, presence of a columellar lamella and in the last whorl being more deviated from the vertical axis. Indoartemon prestoni can be distinguished from I. eburnea by its lower spire with indistinct suture, the last whorl being more deviated from the vertical axis and a widely open umbilicus. Indoartemon prestoni has been placed in Haploptychius and Remarks. An oblique-heliciform shell with 7–7¾ whorls, white, glossy, translucent with distinct sutures. Fine transverse ridges diminish below the periphery. Smooth embryonic shell with about 2½ whorls. Periphery rounded, earlier whorls do not extend beyond the diameter of the axially deflected last whorl. Umbilicus open. Aperture subcircular, peristome thickened and expanded. Apertural dentition composed of one parietal lamella and palatal lamella ( Fig. 3D ).

Oophana , but the presence of a single parietal lamella and a single palatal lamella confirm its position in Indoartemon .

Figures

Fig. 1. Distribution map of Indoartemon spp. and Carinartemis spp. Indoartemon spp (white circle): (1) Indoartemon cingalensis (Benson, 1853); (2) Indoartemon layardianus (Benson, 1853); (3) Indoartemon glacilis (Collett, 1898); (4) Indoartemon eburneus (Pfeiffer, 1861); (5) Indoartemon fuchsianus (Gredler, 1881); (6) Indoartemon bidens (Möllendorff, 1883); (7) Indoartemon tridens (Möllendorff, 1898); (8) Indoartemon laevis (Blanford, 1899); (9) Indoartemon prestoni (Gude, 1903); and (10) Indoartemon medius, new species. Carinartemis spp. (black circle): (1) Carinartemis vesperus, new species; and (2) Carinartemis striatus, new species.

Fig. 3. Shells of Indoartemon spp: A, B, Indoartemon eburneus, (A) lectoype NHMUK 20120255, and (B) specimen CUMZ 5014, with apertural dentition, from Wat Tam Phalom, Loei; C, D, Indoartemon prestoni, (C) lectotype NHMUK 1922.8.29.5, and (D) specimen CUMZ 5015, with apertural dentition, from Wat Tam Ra-Khang, Si Samrong, Sukhothai. E–G, Indoartemon medius, new species, (E) holotype CUMZ 5016 with apertural dentition, (F) paratype CUMZ 5017, and (G) specimen CUMZ 5018 from Tam Lom-Tam Wang, Si Samrong, Sukhothai.