Diplommatina chantaburiensis Dumrongrojwattana, Kamtuptim & Wongkamhaeng 2020

Dumrongrojwattana, Pongrat, Kamtuptim, Chanakarn & Wongkamhaeng, Koraon, 2020, A review of Diplommatina species in eastern Thailand with the descriptions of five new species, Biodiversity Data Journal 8, pp. 57689-57689 : 57689

Diplommatina chantaburiensis Dumrongrojwattana, Kamtuptim & Wongkamhaeng 2020 sp. n.

Materials

Type status: Holotype. Occurrence: catalogNumber: ZRCBUU-0090 ; recordedBy: Pongrat Dumrongrojwattana; individualCount: 1; lifeStage: adult; preparations: dry shell material; Taxon: scientificName: Diplommatinachantaburiensis; Location: country: Thailand; stateProvince: Chanthaburi; locality: Wat Khao Wong Kot, Kanghaengmaeo District ; verbatimCoordinates: 12°52'47.3"N 101°49'13.8"E; georeferenceProtocol: GPS; Identification: identifiedBy: Pongrat Dumrongrojwattana; dateIdentified: 2012; Event: samplingProtocol: hand collecting; eventDate: 2020; habitat: limestone hills; Record Level: language: en; collectionCode: Mollusc; basisOfRecord: PreservedSpecimen Type status: Paratype. Occurrence: catalogNumber: ZRCBUU-0091 ; recordedBy: Pongrat Dumrongrojwattana; individualCount: 29; lifeStage: adult; preparations: dry shell material; Taxon: scientificName: Diplommatinachantaburiensis; Location: country: Thailand; stateProvince: Chanthaburi; locality: Wat Khao Wong Kot, Kanghaengmaeo District ; verbatimCoordinates: 12°52'47.3"N 101°49'13.8"E; georeferenceProtocol: GPS; Identification: identifiedBy: Pongrat Dumrongrojwattana; dateIdentified: 2012; Event: samplingProtocol: hand collecting; eventDate: 2020; habitat: limestone hills; Record Level: language: en; collectionCode: Mollusc; basisOfRecord: PreservedSpecimen

Description

Holotype. Shell height 3.56 mm, shell width 1.64 mm. Aperture height 1.03 mm, aperture width 1.23 mm. Shell width/shell height ratio = 0.46. Aperture width/aperture height ratio = 1.19 (Fig. 2 D).

Paratypes (7 shells). Shell height 2.56-2.85 mm (2.67 ± 0.10 mm) shell width 1.13-1.28 mm (1.24 ± 0.05 mm). Aperture height 0.73-0.85 mm (0.77 ± 0.06 mm). Aperture width 0.73-1.01 mm (0.93 ± 0.08 mm). Shell width/shell height ratio = 0.46 ± 0.02. Aperture width/aperture height ratio = 1.20 ± 0.13. Shell minute dextral, fusiform, translucent, whitish, with about 7 whorls that increase regularly in both size and diameter until the last whorl which is slightly smaller in diameter than the penultimate whorl; protoconch large, whitish, smooth, surface cover with minute pits, consisting of 1 ¼ whorls; teleoconch about 5 ¼ whorls, whitish; sculpture consists of thin, widely-spaced radial ribs which about 9 ribs/mm on the penultimate whorl and about 6 ribs/mm on the body whorl, discernible spiral striae between the ribs absent; sutures deeply impressed; umbilicus closed; aperture rounded; peristome thicked and expanded; columellar lamella is relatively small (Fig. 4 ).

Diagnosis

Shell minute, dextral, translucent, whitish, protoconch large, teleoconch sculpture consisting of widely-spaced axial ribs, spiral striae between the ribs absent; aperture rounded, columellar lamella relatively small, peristome thickened and expanded.

Etymology

The species name " chantaburiensis " refers to Chantaburi, the Province of the type locality.

Distribution

Only known from the type locality.

Taxon discussion

Diplommatina chantaburiensis sp. n. is very similar to D. fusiformis sp. n. Nevertheless, D. chantaburiensis sp. n. has larger protoconch, shell more slender and no spiral striae between the radial ribs. This new species is also similar to the southern species D. hidagai Panha, 1998, but differs by its prominent protoconch, more widely-radial ribs and columellar lamella is poorly developed.

Figures

Figure 2. Four Diplommatina species from eastern Thailand. A) Diplommatina crispata khaochamaoensis Panha et al., 1998, B) D. burapha sp. n., C) D. chadathongae sp. nov. and D) D. chantaburiensis sp. n. Each species shows a frontal view, lateral view, dorsal view and the number of ribs per 0.5 mm on the penultimate whorl and body whorl, respectively.

Figure 4. Synopsis of eastern diplommatind species. A) Diplommatina crispata khaochamaoensis, B-C) Holotype and paratypes of D. burapha sp. n., D-E) Holotype and paratypes of D. chadathongae sp. n., F-G) Holotype and paratypes of D. chantaburiensis sp. n., H-I) Holotype and paratypes of D. fusiformis sp. n. and J-K) Holotype and paratypes of D. khwantongae sp. n. Scale bar = 1 mm.