[Mollusca • 2026] Pagodapalaina euphrosyne • A New open-coiled Microsnail Species of the Genus Pagodapalaina (Caenogastropoda: Diplommatinidae) from Thailand

Pagodapalaina euphrosyne Sutcharit,

 

in Sutcharit, Srisonchai, Maneewan, Jeratthitikul et Annate, 2026. 

หอยกระสวยจิ๋วคลายเกลียวยูโฟรซีน  |  DOI: doi.org/10.1556/1777.2026.00169  

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Abstract

A new species of Pagodapalaina from southern Thailand is described. Pagodapalaina euphrosyne Sutcharit, sp. nov. is characterised by a sinistral, elongate-fusiform shell with an open-coiled teleoconch, well-developed radial ribs restricted to the penultimate and last whorls, and the presence of the parietalis and columellaris. Unlike all other congeners, the detached teleoconch subsequently resumes regular coiling, with the last whorl becoming tightly reattached to the preceding whorl. This previously undocumented developmental pattern raises fundamental questions about current understanding of the developmental constraints governing shell coiling in terrestrial caenogastropods.

Keywords: limestone; endemic species; whorl detachment; ecophenotypic plasticity; micro-CT

A, approximate locations of the type locality of all Pagodapalaina species.
Numbers correspond to: 1) P. acme (Laidlaw, 1949) [= Diplommatina laemsonensis Boonmachai, Bergey & Nantarat, 2023]; 2) P. attenuata (Laidlaw, 1949); 3) P. carinaspinosa (Maassen, 2002); 4) P. diminuta (von Möllendorff, 1891); 5) Pagodapalaina euphrosyne sp. nov.; 6) P. gadutensis (Maassen, 2002); 7) P. hidagai (Panha, 1998a); 8) P. hortulanica Chen, 2025; 9) P. jirasaki (Panha, Kanchanasaka & Burch, 2002); 10) P. karoensis (Maassen, 2002); 11) P. krabiensis (Panha & Burch, 1998); 12) P. lenggongensis (Tomlin, 1941) [= Diplommatina lenggongensis nawawii Davison, 1995]; 13) P. parabates (Laidlaw, 1949); 14) P. pongrati (Panha, Kanchanasaka & Burch, 2002); 15) P. prakayangensis (Panha, 1998b); 16) P. sinistra (Tomlin, 1938) [= Diplommatina prakaiphetensis Boonmachai, Bergey & Nantarat, 2023]; 17.1) P. superba superba (Godwin-Austen & Nevill, 1879); 17.2) P. superba brevior (Laidlaw, 1949); 18) P. suratensis (Panha & Burch, 1998);
B, live snail of  Pagodapalaina euphrosyne sp. nov.

Systematics

Superfamily Cyclophoroidea Gray, 1847

Family Diplommatinidae Pfeiffer, 1856

Genus Pagodapalaina Chen, 2025

Pagodapalaina Chen in Chen et al. 2025: 390, 391.

Type species: Diplommatina acme Laidlaw, 1949, by original designation.

Remark: The genus is characterised by a sinistrally coiled, elongate-fusiform shell with tightly to loosely coiled whorls and a shell surface bearing low ridges to prominent and trough-like radial ribs. The internal lamellar system comprises a well-developed columellaris, a parietalis varying from small to well developed, a vertical palatalis that may be absent, and a constriction ranging from weak to strong.

The genus currently comprises 18 recognised species (Chen et al. 2025, MolluscaBase 2026, this study). Of these, three species are known from Sumatra, Indonesia, and nine species, including the new species described herein, are recorded from Thailand. The northern distributional limit of the genus is currently considered not to extend beyond the Isthmus of Kra (Fig. 1A).

Pagodapalaina euphrosyne sp. nov., paratypes CUMZ 14506 from the type locality.
A, B, adult specimens with narrowly expanded lip;
C, juvenile specimen shows an early stage of penultimate whorl, and onset of tall trough-like radial ribs

Pagodapalaina euphrosyne sp. nov. from the type locality.
A, holotype CUMZ 14505, insets show the aperture with columellaris;
B, paratype CUMZ 14506, juvenile with penultimate and last whorl reattached but lip not yet expanded;
C, paratype CUMZ 14506, insets show the protoconch sculpture

Pagodapalaina euphrosyne Sutcharit, sp. nov.

Diagnosis: Shell small, sinistral, elongate-conical, fusiform, with ∼6 whorls. Earlier teleoconch whorls solute for about two whorls, with smooth surface. Penultimate and last whorls regularly coiled, tightly attached, sculptured with very tall, trough-like radial ribs, and fine spiral striations throughout. Peristome double, expanded. Aperture rounded, with four barriers: one parietalis, two vertical palatalis and one columellaris.

Etymology: The specific epithet, euphrosyne, is a noun in apposition derived from Euphrosyne, one of the Three Graces (Charites) in Greek mythology, the personification of joy, beauty, and elegance. It refers to the graceful and delicate shell morphology of the new species.

  Chirasak Sutcharit, Ruttapon Srisonchai, Nattaphong Maneewan, Ekgachai Jeratthitikul and Supunya Annate. 2026. A New open-coiled Microsnail Species of the Genus Pagodapalaina (Caenogastropoda: Diplommatinidae) from Thailand. Animal Taxonomy and Ecology. DOI: doi.org/10.1556/1777.2026.00169 [16 Sep 2026]

𝙋𝙖𝙜𝙤𝙙𝙖𝙥𝙖𝙡𝙖𝙞𝙣𝙖 𝙚𝙪𝙥𝙝𝙧𝙤𝙨𝙮𝙣𝙚 Sutcharit, 2026 หรือ หอยกระสวยจิ๋วคลายเกลียวยูโฟรซีน ค้นพบที่ถ้ำทะลุ อำเภอละงู จังหวัดสตูล โดยตั้งชื่อชนิดตามรูปร่างเปลือกที่ละเอียดอ่อนและสง่างาม เสมือน “ยูโฟรซีน” ผู้เป็น 1ใน 3เทพีแห่งความงามของเทพปกรณัมกรีก 

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[Mollusca • 2025] Pagodapalaina gen. nov. & Pagodapalaina hortulanica • A New sinistral Genus of Diplommatinidae (Gastropoda: Cyclophoroidea) from the Malay Peninsula and Sumatra, with Description of A New Species from Perak, Peninsular Malaysia

Pagodapalaina Z.-Y. Chen gen. nov.
Pagodapalaina hortulanica gen. & sp. nov.
 Pagodapalaina spp. 

in Chen, Sutcharit et Ablett, 2025.

DOI: doi.org/10.11646/zootaxa.5737.3.5  

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Abstract

A new diplommatinid genus, Pagodapalaina Z.-Y. Chen gen. nov., is erected for several sinistral species from the Malay Peninsula and Sumatra originally assigned to Diplommatina Benson, 1849. In addition, a new species of this new genus, Pagodapalaina hortulanica sp. nov., is described from Perak, Peninsular Malaysia. The genus Pagodapalaina gen. nov., is characterised by a sinistral and conical shell with a mostly keeled periphery; the radula consists of a strong central tooth with a large central cusp and smaller lateral cusps; the basal plate of the central tooth bears two small cusps; the lateral and marginal teeth have very short basal parts. An annotated type catalogue of all known species is presented, with illustrations provided for most taxa. Additionally, Diplommatina laemsonensis Boonmachai, Bergey & Nantarat, 2023 and Diplommatina prakaiphetensis Boonmachai, Bergey & Nantarat, 2023 are recognised as synonyms of Pagodapalaina acme (Laidlaw, 1949) comb. nov., and Pagodapalaina sinistra (Tomlin, 1938) comb. nov., respectively.

Mollusca, Micro snails, new genus, new species, Southeast Asia, systematics, taxonomy

Pagodapalaina hortulanica gen. & sp. nov., holotype, NHMUK 19930124.

Pagodapalaina Z.-Y. Chen gen. nov.

Etymology. The name of the new genus is derived from “Pagoda”, referring to the tiered, keeled and tower-like shape of the shell, reminiscent of East Asian pagodas, and diplommatinid genus name Palaina . This genus name is feminine.

Distribution. Thailand, Malaysia, Indonesia. The known species of the new genus are distributed on the Malay Peninsula and Sumatra.

Pagodapalaina hortulanica sp. nov.

Etymology. We adopted Davison’s manuscript name with minor modification. The name hortulanica, meaning “garden-dwelling” in Latin, may refer to the flourishing vegetation of the type locality.

 Pagodapalaina spp. 

FIG. 3. A. Pagodapalaina lenggongensis, syntype, NHMUK 1943.6.28.1. B. Pagodapalaina hidagai, paratype, CUMZ Di 005. C. Pagodapalaina parabates, holotype, NHMUK 1948.11.12.6. D. Pagodapalaina pongrati, paratype, CUMZ Di 044. E. Pagodapalaina prakayangensis, paratype, CUMZ Di 007. F. Pagodapalaina sinistra, syntype, NHMUK 1938.10.25.4. G. Pagodapalaina superba brevior, holotype, NHMUK 1948.11.12.7, the outline of shell follows Laidlaw (1949). H. Pagodapalaina suratensis, paratype CUMZ Di 029. Scale bars = 1 mm.

FIG. 2. A. Pagodapalaina acme, holotype, NHMUK 1948.11.12.5. B. Pagodapalaina attenuate, holotype, NHMUK 1948.11.12.8. C. Pagodapalaina carinaspinosa, paratype, NHMUK 20030224/1. D. Pagodapalaina diminuta, holotype, SMF 105374/1. E. Pagodapalaina gadutensis, paratype, NHMUK 20030225/1. F. Pagodapalaina jirasaki, paratype, CUMZ Di 041. G. Pagodapalaina karoensis, paratype, NHMUK 20030226/1. H. Pagodapalaina krabiensis, paratype CUMZ Di 032. Scale bars = 1 mm.

ZHE-YU CHEN, CHIRASAK SUTCHARIT, JONATHAN D. ABLETT. 2025. Pagodapalaina, A New sinistral Genus of Diplommatinidae from the Malay Peninsula and Sumatra, with Description of A New Species from Perak, Peninsular Malaysia (Gastropoda: Caenogastropoda: Cyclophoroidea). Zootaxa. 5737(3); 389-400. DOI: doi.org/10.11646/zootaxa.5737.3.5 [2025-12-24]

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[Mollusca • 2026] Georissa meghalayaensis & Acmella bensoni • New Species of Georissa (Gastropoda: Hydrocenidae) and Acmella (Gastropoda: Assimineidae), with new records of Georissa from Northeast India

 

Georissa meghalayaensis sp. nov. and
Acmella bensoni sp. nov. 

 Das & Aravind, 2026

DOI: doi.org/10.5852/ejt.2026.1060.3284 

 x.com/atree_org

Abstract

The present study describes one new species each of Georissa and Acmella from Northeast India. Georissa meghalayaensis sp. nov. and Acmella bensoni sp. nov. are described from Krem Puri, Meghalaya. In addition, Georissa sp. was newly recorded from a soil-leaf litter sample collected at the Sadu Chiru waterfall area in Manipur, and Georissa sarrita was newly recorded from Tuipui in Mizoram. All species were identified based on morphological features, with shell sculpture and suture being the primary distinguishing characters. Notably, all the species from Meghalaya were found inside caves, except for Georissa meghalayaensis (Krem Puri), which was found at the edge of the cave entrance on a wet, moss-covered rocky wall. Further studies are required to confirm the true cavernicolous nature of these microsnails.

Keywords: biodiversity hotspot, cave biodiversity, conchology, conservation, endemics

Georissa meghalayaensis sp. nov. 

Acmella bensoni sp. nov. 

Nipu Kumar Das and Neelavar Ananthram Aravind. 2026. New Species of Georissa (Gastropoda: Hydrocenidae) and Acmella (Gastropoda: Assimineidae), with new records of Georissa from Northeast India.  European Journal of Taxonomy, 1060(1); 1–27. DOI: doi.org/10.5852/ejt.2026.1060.3284 [2026-05-27] 

 x.com/atree_org/status/2065383012116627609

[Mollusca • 2025] Chamalycaeus aduncus • The First Record of an Operculate Micro Land Snail from the Alycaeinae (Caenogastropoda: Cyclophoridae) in Cambodia

 

Chamalycaeus aduncus Jirapatrasilp,   

in Jirapatrasilp, Thi, Chantha, Chourn, Sophea, Jeratthitikul, Pholyotha, Siriwut, Srisonchai, Panha et Sutcharit, 2025. 

www.ruthenica.net/node/6016

 Researchgate.net/publication/390396808 

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This study reports the first record of the operculate micro land snail from the Alycaeinae, Chamalycaeus aduncus Jirapatrasilp sp. nov., also the first new species of the genus in Cambodia, based on a recent survey in Battambang. This new species is similar to Chamalycaeus excisus (Möllendorff, 1887) and C. excisus sublimus Páll-Gergely et Auffenberg, 2019 from the Philippines, in shell size and shape, and the strongly downwards coiling of R3, but differs in having a shorter R2 without any blunt keel, a round aperture without any incision, and a beak- or hook-like basal edge of the outer peristome. 

Keywords: Battambang; Cyclophoroidea; Gastropoda; Mollusca; taxonomy

Chamalycaeus aduncus sp. nov.
A paratype CUMZ 14462/1, and B paratype CUMZ 14462/2, showing a scraping hole at the umbilical side.

. Representative SEM images of Chamalycaeus aduncus sp. nov., holotype CUMZ 14461
 A whole shell in different positions, and B Close-up images of the aperture; white arrows pointing to the beak- or hook-like basal edge of the outer peristome.

Chamalycaeus aduncus Jirapatrasilp sp. nov.

 

Parin JIRAPATRASILP, Sothearen THI, Nasak CHANTHA, Phyroum CHOURN, Chhin SOPHEA, Ekgachai JERATTHITIKUL, Arthit PHOLYOTHA, Warut SIRIWUT, Ruttapon SRISONCHAI, Somsak PANHA and Chirasak SUTCHARIT. 2025. The First Record of an Operculate Micro Land Snail from the Alycaeinae (Caenogastropoda, Cyclophoridae) in Cambodia, with Description of A New Species of Chamalycaeus von Möllendorff, 1897. Ruthenica Russian Malacological Journal. 35(2); 65-72. https://www.ruthenica.net/node/6016

 Researchgate.net/publication/390396808_The_first_record_of_an_operculate_micro_land_snail_from_the_Alycaeinae_Cyclophoridae_in_Cambodia

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[Mollusca • 2026] Operculate Land Snails (Gastropoda: Caenogastropoda: Cyclophoroidea) from Padang Bindu Karst, South Sumatra, Indonesia with the Description of A New Species, Chamalycaeus dayangmerindu

 

c. Chamalycaeus dayangmerindu Aulia & Nurinsiyah, sp. nov.;
d. C. korintjiensis (Páll-Gergely, 2020), holotype (ZMA.MOLL 135672).
a. Stomacosmethis cf. jagori (E. von Martens, 1860); b. S. jagori (E. von Martens, 1860), syntype (SMF 109304); 

in Aulia, Nurinsiyah, Mujiono, Páll-Gergely et Ambarwati, 2026.  

 DOI: doi.org/10.3897/zookeys.1272.179378

Abstract

The study on Cyclophoroidea from Padang Bindu Karst, South Sumatra, was conducted to document the species diversity of the superfamily in the area. The samples, including leaf litter and soil samples, were collected in May–June 2021 and followed by the determination and examination on 2023 to 2024 in the Museum Zoologicum Bogoriense. In total 3,780 specimens from the superfamily Cyclophoroidea were examined. Measurements of the shell and operculum were performed using L.A.S V4. 13.0 and IMAGE J. The research revealed 11 species from three families (Cyclophoridae, Diplomatinidae, Pupinidae) and four subfamilies. Plectostoma kitteli is the most abundant species followed by Stomacosmethis cf. jagori (19.84%) and Diplommatina liwaensis (6.67%). A new species, Chamalycaeus dayangmerindu Aulia & Nurinsiyah, sp. nov. is described. The study also discovered four species endemics to Sumatra with one species among them so far only recorded from Padang Bindu karst area. These findings emphasize the region’s unique biodiversity.

Key words: Biodiversity, conservation, limestone, molluscs, operculum

Shells of Alycaeinae. a. Stomacosmethis cf. jagori (E. von Martens, 1860); b. Stomacosmethis jagori (E. von Martens, 1860), syntype (SMF 109304);
c. Chamalycaeus dayangmerindu sp. nov.; d. Chamalycaeus korintjiensis (Páll-Gergely, 2020), holotype (ZMA.MOLL 135672).

Chamalycaeus dayangmerindu Aulia & Nurinsiyah, sp. nov.

Habitat. Limestone rocks.

Distribution. The species is so far only recorded from Padang Bindu Karst, South Sumatra.

Etymology. The species name Dayang Merindu was inspired by Princess Dayang Merindu, a figure from local folklore. According to the legend, Princess Dayang Merindu ignored the greeting of a man, as she was already married. Her action was then perceived as arrogance, and the man cursed her into stone. The stone associated with this tale is located inside Gua Putri, a karst cave formation in the Padang Bindu area.

 Latifah Nurul Aulia, Ayu Savitri Nurinsiyah, Nova Mujiono, Barna Páll-Gergely and Reni Ambarwati. 2026. Operculate Land Snails (Gastropoda, Caenogastropoda, Cyclophoroidea) from Padang Bindu Karst, South Sumatra, Indonesia with the Description of A New Species, Chamalycaeus dayangmerindu. ZooKeys. 1272: 1-31. DOI: doi.org/10.3897/zookeys.1272.179378 [02 Mar 2026]

[Mollusca • 2025] Hypselostoma pongrati & H. sichomphuense, ... • Two New Species of terrestrial Microsnails of the genus Hypselostoma W.H. Benson, 1856 (Gastropoda: Eupulmonata: Hypselostomatidae) from northeastern Thailand

 

A, B. Hypselostoma pongrati sp. nov. 
 C, D. Hypselostoma sichomphuense sp. nov.  

Tanmuangpak & S. Tumpeesuwan,

in Tanmuangpak, Nahok, Chanlabut, C. Tumpeesuwan et S. Tumpeesuwan, 2025.

 DOI: doi.org/10.3897/zookeys.1265.160661

Abstract

Two new species of hypselostomatid land microsnails, Hypselostoma pongrati Tanmuangpak & S. Tumpeesuwan, sp. nov. from Nong Bua Lamphu Province and H. sichomphuense Tanmuangpak & S. Tumpeesuwan, sp. nov. from Khon Kaen Province, are described based on the morphology of their shell, radula, and genital system. Both new species are very similar in shell shape to H. phupaman from Chaiyaphum Province, possessing a double-keeled last whorl. However, H. pongrati Tanmuangpak & S. Tumpeesuwan, sp. nov. is distinguished by the absence of apertural barriers, whereas H. sichomphuense Tanmuangpak & S. Tumpeesuwan, sp. nov. possesses three apertural barriers, and H. phupaman possesses six or seven. The three species were found on isolated limestone hills in the Chaiyaphum-Khon Kaen-Nong Bua Lamphu-Loei area.

Key words: Apertural barriers, double-keeled last whorl, genital system, limestone hills, radula

Taxonomy

Family Hypselostomatidae Zilch, 1959

Genus Hypselostoma W.H. Benson, 1856

Living Hypselostoma spp.
A, B. Hypselostoma pongrati sp. nov. paratype NHLRU015;
C, D. H. sichomphuense sp. nov. paratype NHLRU033.

 Hypselostoma pongrati Tanmuangpak & S. Tumpeesuwan, sp. nov.

Diagnosis. This new species has a prominent keel on the upper part of the last whorl and a weaker keel on the lower part. Apertural barriers absent (Fig. 3A, G, H, L). Terminal part of the last whorl is adnated to penultimate whorl.

Etymology. This new species is dedicated to the late Pongrat Dumrongrojwattana, our highly respected senior who was an expert on microsnails and who provided us with many land snails references, knowledge, and inspiration.

 Hypselostoma sichomphuense Tanmuangpak & S. Tumpeesuwan, sp. nov.

 

Diagnosis. This new species differs from Hypselostoma phupaman by the presence of a non-prominent lower keel on the last whorl and the absence of basal and parietal apertural barriers. Aperture has three smooth tooth-like swellings (Fig. 4A, G–I), whereas there are no apertural barriers in H. pongrati sp. nov. (Fig. 3A, G–I). Spire shorter than the spire of H. pongrati sp. nov.

Etymology. The specific epithet sichomphuense refers to Si Chomphu District, Khon Kaen Province, northeastern Thailand, where this species was discovered.

 Kitti Tanmuangpak, Benchawan Nahok, Utain Chanlabut, Chanidaporn Tumpeesuwan and Sakboworn Tumpeesuwan. 2025. Two New Species of terrestrial Microsnails of the genus Hypselostoma W.H. Benson, 1856 (Gastropoda, Eupulmonata, Hypselostomatidae) from northeastern Thailand. ZooKeys. 1265: 49-67. DOI: doi.org/10.3897/zookeys.1265.160661

[Mollusca • 2025] Georissa chatra & G. principalis • Phylogenetic and Morphological Evidence for Two New Species of Terrestrial Micro Snail Genus Georissa Blanford, 1864 (Neritimorpha: Hydrocenidae) from Central Thailand

 

หอยทากจิ๋วจุกแดงทรงเจดีย์ • Georissa principalis  Buathanom & Tongkerd, 
หอยทากจิ๋วจุกแดงทรงฉัตร • Georissa chatra  Buathanom & Pholyotha,  

in Buathanom, Tongkerd, Jirapatrasilp, Janjai, Mitchueachart, Annate, Panha, Sutcharit et Pholyotha, 2025. 

Tropical Natural History. Supplement 8 (2025): 

Abstract

This paper introduces two newly discovered endemic micro snails, Georissa chatra Buathanom & Pholyotha, sp. nov. and G. principalis Buathanom & Tongkerd, sp. nov., from limestone hills of Uthai Thani and Nakhon Sawan Provinces in central Thailand. These findings expand the number of Georissa species recorded in Thailand to seven. The taxonomic status and species boundaries of these new species were determined through a comprehensive analysis of comparative morphology and mitochondrial genetics. Georissa chatra sp. nov. is distinguished by a conical shell with tall and prominent carinas. Georissa principalis sp. nov. is characterized by an elongate conical or turreted shell with prominent cord-like spiral ridges, and an operculum with two layers. The cytochrome c oxidase subunit I (COI) phylogeny supports the monophyly of both lineages, but the relationships with other congeners remain unresolved. The analysis also revealed interspecific genetic distances among examined species ranging from 6.8% to 18.6%. Additionally, intraspecific genetic distances are surprisingly high, with 6.1% for G. chatra sp. nov. and 7.5% for G. principalis sp. nov. The observed high intraspecific genetic divergences are likely due to the significant endemism and fragmented distribution of populations within karst ecosystems. As a result, the discovery of these two new species significantly advances our understanding of micro snail diversity and represents a crucial first step in establishing a comprehensive DNA barcode reference library for micro snails in Thailand.

Keywords: COI, Endemic, Limestone, Operculated snail, Morphology, Systematics, Taxonomy, Hydrocenoidea 

Subclass Neritimorpha Koken, 1896

Order Cycloneritida Frýda, 1998

Superfamily Hydrocenoidea Troschel, 1857

Family Hydrocenidae Troschel, 1857

Genus Georissa Blanford, 1864

Living Georissa chatra sp. nov. from a limestone hill near Wat Si Uthum Phon, Nakhon Sawan.
A, B.snails in microhabitats on the limestone wall; insets showing close-up views of (A) a snail hiding in a small crevice and (B) a snail on a bare wall. C–F.four different individuals while climbing slowly on moist tissue paper.

Georissa chatra Buathanom & Pholyotha, sp. nov.

 หอยทากจิ๋วจุกแดงทรงฉัตร

Diagnosis.− Shell minute, conical, dark orange, with tall and prominent carinas: one on upper periphery and one on below periphery.

Etymology.− The specific epithet “chatra” refers to a dome or umbrella-like structure sometimes with multiple tiers or layers, which is used in several Asian royal or state ceremonies, reflecting the distinctive shell shape of this new species.

Shells of Georissa principalis sp. nov.
A–C.paratype CUMZ 15273 from Wat Khao Mano, Nakhon Sawan.

Living Georissa principalis sp. nov.
 A.snail in a microhabitat on the limestone wall at Tham Khao Kaji, Uthai Thani; an inset showing a close-up view of a snail among lichen on a bare wall. B–E.four different individuals while climbing slowly on moist tissue paper, (B, C)from Wat Khao Ruea, Nakhon Sawan and (D, E)from Wat Khao Mano, Nakhon Sawan.

Georissa principalis Buathanom & Tongkerd, sp. nov.

หอยทากจิ๋วจุกแดงทรงเจดีย์

Diagnosis.− Shell minute, elongate, turreted, yellow-orange to light brownish, with about six to seven prominentspiral ridges at the periphery, and operculum with 2 layers.

Etymology.− The name “principalis” is derived from the Latin word meaning “chief” or “leader” and is chosen to honor Her Royal Highness Princess Maha Chakri Sirindhorn for her outstanding leadership in biodiversity conservation in Thailand.

Paniwat BUATHANOM, Piyoros Tongkerd, Parin Jirapatrasilp, Teerangkul Janjai, Bowornluk Mitchueachart, Supunya Annate, Somsak Panha, Chirasak Sutcharit and Arthit Pholyotha. 2025. Phylogenetic and Morphological Evidence for Two New Species of Terrestrial Micro Snail Genus Georissa Blanford, 1864 (Neritimorpha: Hydrocenidae) from Central Thailand. Tropical Natural History. Supplement 8 (2025): 62-78. DOI: 10.58837/tnh.25.8.267040

https://li01.tci-thaijo.org/index.php/tnh/article/view/267040

[Mollusca • 2025] Dicharax devraivasi • A New Micro-snail Species of the Genus Dicharax Kobelt & Möllendorff, 1900 (Caenogastropoda: Cyclophoridae: Alycaeinae), from sacred groves in the northern Western Ghats, India

 

 Dicharax devraivasi

Bhosale, Thackeray, Yadav & Khandekar, 2025

DOI: doi.org/10.61733/jconch/4543

 Researchgate.net/publication/390521141

 

Abstract

 We describe a new micro-snail species of the genus Dicharax based on 16 specimens collected from three sacred groves in Kolhapur District, in the northern Western Ghats of Maharashtra State, India. This species can be easily distinguished from its congeners in several non-overlapping morphological characters: R2 with closely spaced, blunt, elevated ribs; R3 with an inflated, blunt swelling; and basal part of the outer peristome (part close to the umbilicus) is more expanded than the rest of the outer peristome. We also describe and illustrate the living animal, operculum, radula, and jaw. This is the first report of the genus from the northern Western Ghats and extends its known geographic distribution in the Western Ghats by 370 km north. The new species highlights the importance of sacred groves as a biodiversity reservoir and emphasizes the need for in-depth investigations to uncover largely unknown biodiversity at these sites. We also discuss the need for systematic, fine-scale sampling in the northern Western Ghats to reveal mostly unknown land-snail diversity.

Key words. Biodiversity hotspot, Devrai, endemic, Dicharax devraivasi n. sp.,  taxonomy

Living snail of Dicharax devraivasi n. sp.
A, male, holotype NRC-AA-8454. B, female, paratype NRC-AA-8457. C, immature male (not collected) showing semitransparent shell. D, immature male, showing penis (at arrow).

Dicharax devraivasi n. sp.

Etymology. The specific epithet is used as a noun in apposition. It is derived from the Marathi word “devrai”, meaning “sacred grove”, and Sanskrit word “vasi”, meaning “inhabitant of”, as the new species has so far only been reported from multiple sacred grove forests in Kolhapur District, northern Western Ghats of Maharashtra. The suggested English common name is Devrai micro-snail.

Amrut Bhosale, Tejas Thackeray, Omkar Yadav and Akshay Khandekar. 2025. A New Micro-snail Species of the Genus Dicharax Kobelt & Möllendorff, 1900 (Caenogastropoda: Cyclophoridae: Alycaeinae), from sacred groves in the northern Western Ghats, India. Journal of Conchology. 45(3); DOI: doi.org/10.61733/jconch/4543  [5 April 2025]

 Researchgate.net/publication/390521141_A_new_micro-snail_species_of_the_genus_Dicharax_from_the_northern_Western_Ghats_India

[Mollusca • 2025] Clostophis udayaditinus • First Record of the Microsnail Genus Clostophis Benson, 1860 (Eupulmonata: Pupilloidea: Hypselostomatidae) from Cambodia, with Description of A New Species

Clostophis udayaditinus Sutcharit & Panha,

in Sutcharit, Thi, Chantha, Chourn, Sophea, Jeratthitikul, Pholyotha, Siriwut, Srisonchai et Panha, 2025. 

Journal of Conchology. 45(3); 

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Abstract

 Specimens of a new species of hypselostomatid microsnail, Clostophis udayaditinus Sutcharit & Panha, n. sp., were collected from the limestone hills area in Battambang Province, western Cambodia. Besides being a species new to science, this discovery represents a new country record for the genus. The new species differs from all other congeners by its concave-conical shell, with apertural dentition four in number, and hooked parietal and columellar lamellae. Living snails were found crawling on the walls in a cave, and the snails have a colourless, semitransparent soft body.

Key words. Angkor Kingdom, endemic species, limestone, pulmonates, taxonomy

Clostophis udayaditinus n. sp.  from the type locality.
A–C, paratype CUMZ 14466 of living snails crawling on wet tissue paper (three snails at different angles; all shell widths about 1.3 mm). D, light microscope image of paratype CUMZ 14467 with enlarged aperture at different angles.

 Abbreviations: c = columellar lamella, ip = infraparietal lamella, p = parietal lamella, pl = palatal plica.

Clostophis udayaditinus n. sp. from Battambang, Cambodia.
A, holotype CUMZ 14441 with enlarged aperture at different angles, and enlarged columellar lamella and palatal plica, and B, C, protoconch. D, paratype CUMZ 14446 from the type locality.

 Abbreviations: c = columellar lamella, ip = infraparietal lamella, p = parietal lamella, pl = palatal plica.

Family Hypselostomatidae Zilch, 1959 

Clostophis Benson, 1860

 Type species. Clostophis sankeyi Benson, 1860, by monotypy. 

Remarks. Until now, the genus Clostophis has been known to be widely distributed from Peninsular Malaysia to Myanmar, mainland Indochina, and southern China (Páll-Gergely et al. 2020; Páll-Gergely & Hunyadi 2022; MolluscaBase Eds 2024). There are 20 species known from Cambodia, including the new species, described here.

Clostophis udayaditinus Sutcharit & Panha, n. sp. 

Diagnosis. Shell concave-conical, with long, descending tuba and expanded peristome. Apertural dentition four: consisting of one hooked parietal lamella, one small infraparietal lamella, one large, strong palatal plica, and one hooked columellar lamella. Umbilicus wide.

Etymology. The species name udayaditinus is from “udayadit-”, and the suffix “-inus”, meaning possession or belonging to. This name is a memorial to King Udayadityavarman II, who ruled the Angkor Kingdom around 1100 A.D. He also ordered the building of the Bannan Temple (Higham 2014), which became the name of the hill—the type locality of this new species.

Chirasak Sutcharit, Sothearen Thi, Nasak Chantha, Phyroum Chourn, Chhin Sophea, Ekgachai Jeratthitikul, Arthit Pholyotha, Warut Siriwut, Ruttapon Srisonchai and Somsak Panha. 2025. First Record of the Microsnail Genus Clostophis Benson, 1860 (Eupulmonata: Pupilloidea) from Cambodia, with Description of A New Species. Journal of Conchology. 45(3); DOI. doi.org/10.61733/jconch/4538  [23 February 2025] 

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[Mollusca • 2020] Diplommatina fusiformis, D. burapha, ... • A Review of Diplommatina Species (Gastropoda: Diplommatinidae) in eastern Thailand with the Descriptions of Five New Species

[A] Diplommatina fusiformis spec. nov. หอยกระสวยจิ๋ว,  

[B-E] D. khwantongae spec. nov. หอยกระสวยจิ๋วคณิตา, 

D. crispata khaochamaoensis Panha et al., 1998, 

  หอยกระสวยจิ๋วบูรพา D. burapha sp. n.,   

หอยกระสวยจิ๋วชฎาทอง D. chadathongae Kamtuptim, Dumrongrojwattana & Wongkamhaeng sp. nov.  

หอยกระสวยจิ๋วจันทบุรี  D. chantaburiensis sp. n. 

 in Dumrongrojwattana, Kamtuptim & Wongkamhaeng, 2020

 DOI: 10.3897/BDJ.8.e57689

Abstract

Background: Microsnails in the genus Diplommatina Benson, 1849 from eastern Thailand are revised, based on the collection of the Zoological Research Collection, Burapha University, Chonburi Province, Thailand and on recently-collected materials.

New information: Five new species, Diplommatina burapha sp. n., D. chadathongae sp. n., D. chantaburiensis sp. n., D. fusiformis sp. n. and D. khwantongae sp. n., are described as new to science. The geographic distribution of these eastern species is presented.

Keywords: Diplommatina, Diplommatinidae, taxonomy, Thailand

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.

Two Diplommatina species from eastern Thailand.
A) D. fusiformis spec. nov., B-E) D. khwantongae spec. nov.,
B) Holotype, C-D) Living snail. (Photos by Ms. Rattanawadee Tekavong).
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.

  

 Pongrat Dumrongrojwattana, Chanakarn Kamtuptim and Koraon Wongkamhaeng. 2020. A Review of Diplommatina Species in eastern Thailand with the Descriptions of Five New Species. Biodiversity Data Journal. 8: e57689. DOI: 10.3897/BDJ.8.e57689

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 สด ๆ ร้อน ๆ หอยกระสวยจิ๋วชนิดใหม่ของโลก 5 ชนิด จากภาคตะวันออก ได้แก่ 

1. หอยกระสวยจิ๋วบูรพา (Diplommatina burapha Dumrongrojwattana, Kamtuptim & Wongkamhaeng, 2020) จากจังหวัดสระแก้ว ตั้งตามภูมิภาคที่พบ คือ ภาคตะวันออกและสอดคล้องกับชื่อมหาวิทยาลัย "บูรพา"

2. หอยกระสวยจิ๋วชฎาทอง (Diplommatina chadathongae Kamtuptim et al., 2020 in Dumrongrojwattana et al., 2020) หอยชนิดนี้ตั้งชื่อเพื่อเป็นเกียรติและระลึกถึงคุณแม่ของนางสาวชนากานต์ ขำทับทิม นิสิตชั้นปีที่ 4 ภาควิชาชีววิทยา หนึ่งในผู้ร่วมงานวิจัยชิ้นนี้

3. หอยกระสวยจิ๋วจันทบุรี (Diplommatina chantaburiensis Dumrongrojwattana et al., 2020) ตั้งชื่อตามจังหวัดจันทบุรี ที่ซึ่งพบหอยกระสวยจิ๋วชนิดนี้เป็นครั้งแรก

4. หอยกระสวยจิ๋ว (Diplommatina fusiformis Dumrongrojwattana et al., 2020) ตั้งชื่อตามรูปทรงเปลือกหอยที่เป็นทรงกระสวย

5. หอยกระสวยจิ๋วคณิตา (Diplommatina khwantongae Dumrongrojwattana et al., 2020) ตั้งชื่อให้เป็นเกียรติและแสดงความระลึกถึง นางสาวคณิตา ขวานทอง หรือ พะลอย ของอาจารย์และเพื่อน ๆ ร่วมรุ่น นิสิตผู้ทำการศึกษาและค้นพบหอยกระสวยจิ๋วชนิดนี้ ผู้จากไปก่อนวัยอันควร

ผลการศึกษาครั้งนี้ ทำให้จำนวนชนิดของหอยกระสวยจิ๋วในภาคตะวันออก เพิ่มขึ้นจากเดิมที่รายงานไว้เพียง 1 ชนิด คือ หอยกระสวยจิ๋วเขาชะเมา (Diplommatina crispata khaochamaoensis) เพิ่มขึ้นเป็น 6 ชนิด

[Mollusca • 2023] Sohtsuia diting • Integrative Taxonomy revealing A Troglobitic New Genus of Diplommatinidae (Gastropoda: Caenogastropoda: Cyclophoroidea) from Jiangxi, China

Sohtsuia Z.-Y. Chen,
Sohtsuia diting Chen, Lyu & Chen, 2023 

DOI: 10.11646/zootaxa.5231.4.10 

 Researchgate.net/publication/367636325

Abstract

A new subterranean diplommatinid snail is described and illustrated from Jiangxi, China. The species is diagnosed by its cylindrical-fusiform shell and absence of internal columellar lamellae and parietal folds. The morphological and molecular phylogenetic characterization of the new species supports the erection of a new genus, Sohtsuia Z.-Y. Chen, gen. nov. A molecular phylogeny of representative East Asian continental species of Diplommatina Benson, 1949 is provided and the relationships of the new genus are discussed. Sohtsuia diting sp. nov. is described as new species.

Keywords: Gastropoda, China, Diplommatinidae, new genus, new species, systematics, taxonomy 

 

Shell of Sohtsuia diting gen. & sp. nov. Scale bar: 1 mm

Sohtsuia diting sp. nov.  

 

  Type locality (A) and living specimens (b) of Sohtsuia diting gen. & sp. nov.  

Zhe-Yu Chen, Zhi-Tong Lyu and Hui-Ming Chen. 2023. Integrative Taxonomy revealing A Troglobitic New Genus of Diplommatinidae from Jiangxi, China (Gastropoda: Caenogastropoda: Cyclophoroidea). Zootaxa. 5231(4); 491-500. DOI: 10.11646/zootaxa.5231.4.10

  Researchgate.net/publication/367636325_Integrative_taxonomy_revealing_a_troglobitic_new_genus_of_Diplommatinidae_from_Jiangxi_China