Piyoros Tongkerd

Chulalongkorn University · Department of Biology

The poorly studied leatherleaf slug genus Valiguna in Thailand was carefully investigated. Members of this genus are phenotypically similar, making their identification very challenging. This study clarifies the taxonomic status of all Valiguna species in Thailand by combining morphological and anatomical studies with DNA barcoding. Monophyly of al...

The Malay Peninsula has traditionally been considered to harbour a diverse land-snail fauna, both in terms of a high species richness and a wide variety of conchological traits, especially within the limacoid land snails. A recent survey along the Malay Peninsula of southern Thailand discovered an overlooked limacoid taxon “ Trochomorpha ” sculptic...

The semislug Megaustenia siamensis, commonly found in Thailand, is notable for its exceptional capacity to produce biological adhesives, enabling it to adhere to tree leaves even during heavy rainfall. In this study, we generated the first reference genome for M. siamensis using a combination of three sequencing technologies: Illumina’s short-read,...

The mechanism of bioluminescence in the luminous land snails remains largely unknown. Here, we analyzed basic biochemical properties of the luminous land snail, Quantula weinkauffiana . The luminescence activity was extracted from the light organ located near the mouth using a neutral buffer containing detergent. The reaction of the crude buffer ex...

Land snails were collected for the project ‘Conserving Myanmar’s Karst Biodiversity’ from the limestone karsts in Mon, Kayin, and Shan states and in the regions of Tanintharyi and Mandalay between 2015 and 2017, through cooperation with Fauna and Flora International (FFI) and the Forestry Department of Myanmar. Here, we report on a portion of the c...

The mysterious world of the bioluminescent molluscs in terrestrial ecosystems is mesmerizing, but Quantula striata was previously the only terrestrial mollusc known to be luminescent. Here, we document the new discovery of bioluminescence in four land snails, namely Phuphania crossei , P. globosa , P. carinata , and P. costata. Our observations est...

The Euconulidae is a globally distributed land snail family but there is no record of this family from Thailand. In this study, we describe a new genus, Siamoconus gen. nov., based on comparative studies of the shell characteristics, external morphology of animals, radula, genital and spermatophore structures, and molecular phylogeny. We performed...

The snorkel snail genus Rhiostoma Benson, 1860 is comprised of terrestrial cyclophorid snails with wide-ranging species diversity and radiation in Southeast Asia. The typical characters of the genus are a depressed shell, a detached and descending portion of the last whorl with a distinctive peristomal breathing device attached, and a calcareous cu...

Lingulidae are often considered living fossils, because they have shown little morphological change since the Paleozoic. Limited morphological variation has also made the taxonomic study of living lingulids challenging. We investigated species diversity and phylogenetic relationships of extant lingulids and show that they are substantially more div...

Thai limestone karsts are known to contain a rich biodiversity of animals, especially terrestrial snails, but still require further intensive exploration to evaluate their biodiversity. To date, only a few studies on the limestone karst-inhabiting land snail genera have been published. The present work focuses on the species diversity and phylogene...

This study reviews the Dicharax species in Thailand. Altogether ten Dicharax species are reported, four of which are new to science and described herein. They are Dicharax borealis Jirapatrasilp & Páll-Gergely sp. nov., Dicharax burchi Jirapatrasilp & Páll-Gergely sp. nov., Dicharax panhai Jirapatrasilp & Páll-Gergely sp. nov. and Dicharax pongrati...

Indochina land snails of the family Ariophantidae are in need of thorough systematic revision. Here we comprehensively revise the systematics of the large-shelled, sinistral (counterclockwise) coiling snails from Thailand and Peninsular Malaysia. Molecular phylogeny based on mitochondrial ( coi and 16S) and nuclear (28S) gene sequences demonstrates...

Members of the terrestrial snail family Dyakiidae from Southeast Asia show a distinct geographical distribution pattern and possess different degrees of complexity in their amatorial organ gland. This study is the first molecular phylogeny of ten of the 12 genera in this family, performed to provide insights into the origin of Dyakiidae and the evo...

Members of the terrestrial snail family Dyakiidae from Southeast Asia show a distinct geographical distribution pattern and possess different degrees of complexity in their amatorial organ gland. This study is the first molecular phylogeny of ten of the 12 genera in this family, performed to provide insights into the origin of Dyakiidae and the evo...

Members of the land snail genus Sarika Godwin-Austen 1907 are superficially similar and difficult to differentiate by their shell morphology so that their species limits are still unclear. In order to resolve the taxonomy of this group, a phylogenetic reconstruction of Sarika is presented, based on morphological and anatomical characters, as well a...

Southeast Asia boasts a high diversity of carnivorous terrestrial snails in the family Streptaxidae. Six genera are now recognized in this region, mainly classified by the traditional characters of shell morphology, especially the configuration of the apertural dentition and eccentric shell shape. More recently, genital characters have been used to...

The endemic terrestrial Crown Snail from Southern Thailand formerly in Macrochlamys Gray, 1847 is now described as Taphrenalla Pholyotha & Panha gen. nov., based on comparative morphology and molecular data. Overall, eleven Taphrenalla species are now recognized, including two nominal species: T. asamurai and T. diadema . A total of nine new specie...

Knowledge of Myanmar land snails is based on the late eighteenth to early twentieth century literature and many species need to be re-investigated, especially in the genera Macrochlamys Gray, 1847 and Sarika Godwin-Austen, 1907. In order to update this knowledge, this paper presents information on these two related genera based on new materials fro...

Nucleotide sequences of a 658 bp DNA fragment of the cytochrome c oxidase subunit 1 were used to investigate the population structure, phylogeographical pattern and genetic variation of Pontodrilus longissimus Seesamut and Panha, 2018 sampled from 16 localities along the coastline of Thailand. Bayesian inference, maximum likelihood analyses and the...

Recent conceptual and practical advances in phylogenetic species delimitation have enabled progressively robust biodiversity studies. Delimiting species in widespread taxa is an intriguing problem; the edible operculated land snail Cyclophorus volvulus (Müller, 1774) is a good example since it shows a high degree of shell and color variation along...

Phylogenetic relationships of two morphologically similar scolopendrid genera, Rhysida Wood, 1862, and Alluropus Silvestri, 1912, were investigated based on broad-scale taxonomic sampling from SE Asia, India and Australia. Morphological revision and molecular phylogenetics using three loci validate seven Rhysida species in SE Asia and Australia: R....

Metaphire peguana (Megascolecidae) is a terrestrial earthworm that was found to be widely distributed throughout the whole of Penang state during our field collecting. The differences in the average length and diameter of M. peguana between the island and mainland Penang population were correlated with their behavior and the environmental parameter...

The centipede genus Scolopendra in mainland Southeast Asia is reviewed taxonomically based on morphological characters, informed by a molecular phylogenetic analysis using sequences from three mitochondrial and nuclear genes (COI, 16S rRNA and 28S rRNA). Eight nominal species of Scolopendra, namely S. morsitans Linnaeus, 1758, S. subspinipes Leach,...

The collection of the Southeast Asian tree snail genus Amphidromus Albers, 1850 at the Natural History Museum, London includes more than 100 lots of type specimens representing 85 name-bearing types, 9 paratypes and 6 paralectotypes, and one nomen nudum. Lectotypes are here designated for A. cambojien-sis, A. perakensis globosus, A. columellaris gl...

The collection of land caenogastropod snails in the genus Cyclophorus Monfort, 1810 housed in the Natural History Museum, London (NHM), includes 52 type lots. Lectotypes have been designated for 43 available species-level names to stabilize existing nomenclature, two previously designated lectotype, two holotypes, one paratype, one syntype, one pos...

Specimens of the operculated land snail genus Pterocyclos Benson, 1832, from Thailand and Peninsular Malaysia were investigated based on their shell characteristics. Type specimens and topotypic material were studied and compared with newly collected specimens. Two new species are described, viz. Pterocyclos diluvium Sutcharit & Panha, new species,...

The semi-aquatic freshwater earthworm genus Glyphidrilus Horst, 1889 from Thailand was investigated based on extensive recent collecting. The species in this genus were characterized by their external and internal morphological characters of the location of wings, genital openings, genital organ structures and their locations, as well as the dimens...