[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] Fansipanica milae, Vinatachea porcellana, ... • New taxa of Camaenidae (Gastropoda: Stylommatophora) from northern Vietnam

Fansipanica milae Páll-Gergely & Dedov,

   

in Páll-Gergely, Gojšina et Dedov, 2026.

DOI: doi.org/10.3897/zookeys.1280.185160

 

Abstract

The following new taxa are described from northern Vietnam: Fansipanica milae Páll-Gergely & Dedov, gen et sp. nov., Ducanhia Páll-Gergely, gen. nov. (type species: Helix balansai Morlet, 1886), Vinatachea porcellana Páll-Gergely, sp. nov. The reproductive anatomy of all three species is described. Helix (Chloritis) gereti Bavay & Dautzenberg, 1900 is moved to Fansipanica gen nov., and Camaena delsaerdti Thach & F. Huber, 2018 is moved to Vinatachea.

Key words: Anatomy, Fansipan Mountains, new species, systematics, taxonomy

Fansipanica milae gen. et sp. nov. 
A–C. Living specimen, D. Habitat. 

 

Fansipanica milae Páll-Gergely & Dedov, gen et sp. nov., 

Ducanhia Páll-Gergely, gen. nov. 

(type species: Helix balansai Morlet, 1886), 

Vinatachea porcellana Páll-Gergely, sp. nov. 

Barna Páll-Gergely, Vukašin Gojšina and Ivailo Dedov. 2026. New taxa of Camaenidae from northern Vietnam (Gastropoda, Stylommatophora). ZooKeys. 1280: 365-392. DOI: doi.org/10.3897/zookeys.1280.185160 [28 May 2026]

[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 

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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] 

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[Mollusca • 2022] Burmochlamys fasciola, B. albida, B. versicolor, ... • Uncovering local Endemism from southeastern Myanmar: Description of the New Karst-associated Terrestrial Snail Genus Burmochlamys (Eupulmonata: Helicarionidae)

 

Burmochlamys Pholyotha & Panha,
A Burmochlamys fasciola sp. nov. paratype showing left and right lateral views;  
D B. albida sp. nov. paratype; E B. moulmeinica sp. nov. paratype;
F B. versicolor sp. nov. paratype; G B. whitteni sp. nov. paratype 

in Pholyotha, Sutcharit, Lin et Panha, 2022.   

 DOI: doi.org/10.3897/zookeys.1110.82461 

Abstract

Salween River basin’s karst ecosystems in southeastern Myanmar remain largely unexplored and are likely to harbour a high terrestrial snail diversity that are often associated with high levels of snail endemism. Here, an outstanding group of new karst-associated terrestrial snails, Burmochlamys gen. nov., are discovered. A study of the comparative morphological and anatomical data reveals that the reproductive tract and radula of this new genus are closely related to the helicarionid genus Sophina Benson, 1859 but shell morphology (shape, size, and sculpture) and mantle extensions are distinct from the latter genus. Burmochlamys gen. nov. now consists of four known nominal species, B. cassidula comb. nov., B. cauisa comb. nov., B. perpaula comb. nov., and B. poongee comb. nov., and five new species; B. albida sp. nov., B. fasciola sp. nov., B. moulmeinica sp. nov., B. versicolor sp. nov., and B. whitteni sp. nov. The highlight is that the members of the new genus show site-specific endemism, being restricted to karstic habitat islands of the Salween River basin. In addition, the discovery supports that the unique and complex structure of Salween River basin’s karst ecosystems are habitats in which the terrestrial malacofauna have speciated and become endemic.

Keywords: Diversity, endemic, Indochina, land snail, limestone, Salween River basin, taxonomy

Family Helicarionidae Bourguignat, 1877

Subfamily Durgellinae Godwin-Austen, 1888

Living snails of Burmochlamys species
A Burmochlamys fasciola sp. nov. paratype CUMZ 14214 showing left and right lateral views B B. cassidula specimen CUMZ 14209
C B. poongee specimen CUMZ 14210 D B. albida sp. nov. paratype CUMZ 14212
E B. moulmeinica sp. nov. paratype CUMZ 14217 F B. versicolor sp. nov. paratype CUMZ 14219 G B. whitteni sp. nov. paratype CUMZ 14222.

Genus Burmochlamys Pholyotha & Panha, gen. nov.

 

Type species: Burmochlamys fasciola sp. nov., by original designation.

Etymology: The name combines Burmo in reference to Burma, the historical name of Myanmar, and the Greek word chlamys meaning mantle or cloak in reference to land snail with well-developed mantle extensions. Therefore, the generic name means the Burmese land snail with the well-developed mantle extensions. The gender of the new generic name is feminine.

Diagnosis: Shell subglobose to globose, small size, little high spire, and sculptured with spiral furrows and undulating radial lines. Snail with five well-developed mantle extensions; caudal horn raised. Genitalia with penial retractor muscle attached at tip of epiphallic caecum; gametolytic organ with rather short to moderate cylindrical duct and bulbous sac; well-developed dart apparatus; flagellum absent. Radula with large monocuspid central tooth and attached by two smaller teeth; laterals and marginals undifferentiated, large monocuspid, and at base of each tooth on outer side attached by a smaller tooth.

B. cassidula comb. nov., B. cauisa comb. nov., 

B. perpaula comb. nov., and B. poongee comb. nov., 

and five new species; B. albida sp. nov., B. fasciola sp. nov., 

B. moulmeinica sp. nov., B. versicolor sp. nov., and B. whitteni sp. nov.

A adult of Burmochlamys moulmeinica sp. nov. while climbing slowly on the karst wall after raining at Lun Nya Pagoda B mating pairs of B. versicolor sp. nov. on the karst wall at Bayin Nyi Cave
C B. versicolor sp. nov. eaten by the carnivorous snail Carinartemis sp. on the karst wall at Bayin Nyi Cave D B. cassidula eaten by the carnivorous snail Haploptychius sp. on the karst wall at Kaw Gon Cave. 

 Arthit Pholyotha, Chirasak Sutcharit, Aung Lin and Somsak Panha. 2022. Uncovering local Endemism from southeastern Myanmar: Description of the New Karst-associated Terrestrial Snail Genus Burmochlamys (Eupulmonata, Helicarionidae).  ZooKeys. 1110: 1-37. DOI: doi.org/10.3897/zookeys.1110.82461 

[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 • 2021] Hemiplecta nemorosa • Systematic Review of the Dextral Hemiplecta Albers, 1850 (Eupulmonata: Ariophantidae) from Thailand with Description of A New Species and List of All the Indochinese Species

A Hemiplecta humphreysiana from Singapore; B Hemiplecta distincta from Saraburi, Thailand;
D, E Hemiplecta funerea from Nan, Thailand D yellow shell form and E dark shell form;
  F Hemiplecta esculenta from Chiang Mai, Thailand; 

Hemiplecta nemorosa  Sutcharit & Panha, 2021

DOI: 10.3897/zookeys.1047.65735

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Abstract

The genus Hemiplecta is a group of large-sized land snails which have long been used as a food resource by Indochinese people. There are five dextral and four sinistral species currently recognized from Thailand. The dextral group is comprised of two previously recorded species (H. humphreysiana and H. distincta), two newly recorded species (H. funerea and H. esculenta), and one new species (Hemiplecta nemorosa sp. nov.) from northern Thailand is being proposed. We reassessed the diagnostic characters of the genitalia, mantle edge, and radula. Specimens were classified into the genus Hemiplecta on the basis of the penial verge and shell lobe, and on the characters of a bulbous gametolytic sac without a gametolytic duct. A complete species list, together with photographs of the name-bearing types or authenticated specimens and the taxonomic status of Hemiplecta s.l. that are known from Indochina including Peninsular Malaysia and Myanmar, is provided for the first time. In total, this species list contains 39 available nominal species names described from this area. Type or authentic specimens can be located for 37 nominal species names, of which 25 are illustrated herein and the other 12 were recently illustrated. However, two available species-level names could not be traced to any type specimens. In addition, lectotypes of H. funerea and H. pluto are designated herein to stabilize the names.

Keywords: Conservation, edible snails, lectotype, Southeast Asia, taxonomy type specimen

Living snail.
A Hemiplecta humphreysiana from Singapore (width about 45 mm)
B, C Hemiplecta distincta B from Saraburi, Thailand (width about 65 mm) and C mating pairs
D, E Hemiplecta funerea from Nan, Thailand (width about 50 mm) D yellow shell form and E dark shell form (width about 50 mm)  
F Hemiplecta esculenta from Chiang Mai, Thailand (width about 30 mm).

 Chirasak Sutcharit and Somsak Panha. 2021. Systematic Review of the Dextral Hemiplecta Albers, 1850 (Eupulmonata, Ariophantidae) from Thailand with Description of A New Species and List of All the Indochinese Species. ZooKeys. 1047: 101-154. DOI: 10.3897/zookeys.1047.65735

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[Mollusca • 2025] Discartemon sirindhornae • A New Discartemon Species (Eupulmonata: Streptaxidae) from Peninsular Thailand

 

Discartemon sirindhornae Artsamart & Siriboon,

in Artsamart, Rungruangdejwattana, Camngam, Raksasin, Sutcharit, Jirapatrasilp et Siriboon, 2025.   

หอยนักล่าสิรินธร  ||  DOI: doi.org/10.58837/tnh.25.8.267107  

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Abstract

Discartemon sirindhornae Artsamart & Siriboon, sp. nov. is described and illustrated based on specimens collected from Chumphon Province in Peninsular Thailand. The new species possesses a flattened shell with a slightly convex spire, a weakly angular last whorl, and an intermediately expanded whorl. The apertural dentition consists of one parietal lamella, one ridge-like and one small lower palatal, one small basal, and one small columellar lamella. The penis is long, slender and twisted distally, with penial hooks separated by elevated longitudinal folds. The current study advances knowledge of the streptaxid land snail species in Thailand and emphasizes the value of limestone habitats for preserving biodiversity.

Keywords: carnivorous snail, systematics, genitalia, limestone, endemic species

Discartemon sirindhornae

หอยนักล่าสิรินธร 

 

Palod Artsamart, Pongpisit Rungruangdejwattana, Chalinee Camngam, Chutathip Raksasin, Chirasak Sutcharit, Parin Jirapatrasilp and Thanit Siriboon. 2025. Discovery of A New Discartemon Species (Eupulmonata: Streptaxidae) from Peninsular Thailand.  Tropical Natural History. Suppl. 8; 380-389. DOI: doi.org/10.58837/tnh.25.8.267107 [2025-10-20]

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[Mollusca • 2025] Siamopotaxis principalis & S. thailandensis • A New Helicarionoidean Land Snail Genus Siamopotaxis gen. nov. (Eupulmonata: Helicarionidae) from Thailand based on Molecular Phylogenetic and Morphological Evidence

 

Siamopotaxis Pholyotha, gen. nov. 
Siamopotaxis principalis Pholyotha, sp. nov. 
Siamopotaxis thailandensis Pholyotha, sp. nov.

in Pholyotha, Tongkerd, Panha et Sutcharit, 2025.  

 DOI: doi.org/10.58837/tnh.25.8.267115 

Abstract

The new helicarionoidean land snail genus Siamopotaxis Pholyotha, gen. nov. is described for two new species, Siamopotaxis principalis Pholyotha, sp. nov. and Siamopotaxis thailandensis Pholyotha, sp. nov., both from Thailand. The new genus is characterised by a medium-sized, globose, high-spired, cream-coloured shell, with one or two supraperipheral bands, a rounded last whorl, a short epiphallic caecum, an elongated dart apparatus, and many radular teeth with pectiniform cusps. Siamopotaxis principalis sp. nov. differs from S. thailandensis sp. nov. by the presence of one spiral band, whereas the latter species has two spiral bands. A DNA sequence analysis of mitochondrial COI and 16S DNA, and nuclear 28S DNA gene fragments, supports the systematic placement of these new taxa and confirms that Siamopotaxis gen. nov. as a distinct clade within the Helicarionidae.

Keywords: Diversity, Endemic, Indochina, Land snail, Limestone, Taxonomy

A–D Siamopotaxis principalis sp. nov., A holotype CUMZ 15186, and B–D paratypesCUMZ 15257 from the type locality. 
E, F  Siamopotaxis thailandensis sp. nov., E holotype CUMZ 15116 and F paratype CUMZ 15117 from the type locality 

Photographs of living snails.
A, B Siamopotaxis principalis sp. nov., paratype CUMZ 15257, A right side, B left side.
C, D Siamopotaxis thailandensis sp. nov., C right side of paratype CUMZ 15117, D left side of paratype CUMZ 14924.

หอยหางดิ้นเจ้าฟ้า Siamopotaxis principalis 

Arthit Pholyotha, Piyoros Tongkerd, Somsak Panha and Chirasak Sutcharit. 2025. Discovery of a New Helicarionoidean Land Snail Genus Siamopotaxis gen. nov. (Eupulmonata: Helicarionidae) from Thailand Based on Molecular Phylogenetic and Morphological Evidence. Tropical Natural History. Suppl. 8; 121-139. DOI: doi.org/10.58837/tnh.25.8.267115 [2025-10-14]

[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] Theobaldius? konkanensis • A New Species of cyclophorid land snail (Gastropoda: Caenogastropoda: Cyclophoridae) from the coastal regions of Maharashtra, India

Theobaldius? konkanensis 

Bhosale, Thackeray, Yadav, Khandekar, White & Raheem, 2025

DOI: doi.org/10.1080/13235818.2025.2462864 

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ABSTRACT

We describe a new species of cyclophorid land snail, Theobaldius? konkanensis n. sp., from the coastal and lower elevational region of the northern Western Ghats in Maharashtra, India. Theobaldius? konkanensis n. sp. can be differentiated from other species of Theobaldius Nevill, 1878 by the combination of a conoidally depressed shell with a more elevated spire, a deep notch on the apertural margin overhung by a prominent raised fold, and an operculum with the edges of the whorls conspicuously raised and bearing short spines. We provide a detailed description of the new species, focusing on the shell, operculum, jaw and radula, and the external morphology of the living animal; we map its distribution using recently collected data, and compare it with other species of Theobalidus and other cyclophoroidean genera.

KEYWORDS: Konkan, northern Western Ghats, operculum, taxonomy, Theobaldius?

Theobaldius? konkanensis n. sp.

 

Amrut Bhosale, Tejas Thackeray, Omkar Yadav, Akshay Khandekar, Tom S. White and Dinarzarde C. Raheem. 2025. A New Species of cyclophorid land snail (Caenogastropoda: Cyclophoridae) from the coastal regions of Maharashtra, India. Molluscan Research. 45(2); 157-169. DOI: doi.org/10.1080/13235818.2025.2462864 [11 Mar 2025] 

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