ISSN 2755-3531
First interception of Xeropicta derbentina in the Benelux (Gastropoda: Geomitridae)
Louis Bronne & Milan Lassman
Abstract. In October 2025, an adult live specimen of Xeropicta derbentina (Krynicky, 1836) was discovered in an organic grocery store in Brussels, representing the first record of this species in Belgium. Fertilized eggs were laid by the individual and successfully hatched. Although the animal was found in vegetables it has most certainly reach Belgium adhering to other products. Xeropicta derbentina could potentially establish in North-western Europe helped by urban microclimates. Early detection and monitoring of this invasive species, particularly via citizen science, are therefore essential.
Published 4 January 2026
DOI. https://doi.org/10.61733/jconch/4561
Occurrence of golden Portuguese Oysters (Crassostrea angulata) in farmed populations in Taiwan
Yu-Ai Chen, Ren-Shyang Tai, Te-Yu Liao & Li-Lian Liu
Abstract. Although selective breeding for shell colour has been established in oysters, the prevalence of golden oysters in wild or farmed populations remains poorly known. In the present study, we investigated the occurrence of the golden Portuguese Oyster, Crassostrea angulata (Lamarck, 1819), in aquaculture areas in Taiwan. Our results showed no significant difference in the proportion of golden oysters among the Taixi, Qigu, and Kinmen sites (one-way ANOVA, p > 0.05), with respective averages of 9.7 ± 5.2%, 9.5 ± 5.4%, and 8.4 ± 5.8%. The consistent presence of approximately 10% golden oysters across all three locations may be attributed to the year-round availability of oyster spat and the absence of site-specific selective pressures.
Key words. Magallana angulata, shell colour, COI
Published 27 January 2026
DOI. https://doi.org/10.61733/jconch/4562
Dan Minchin
Abstract. The Zebra Mussel, Dreissena polymorpha, was introduced to Lough Derg, in the Shannon catchment, Ireland, during the early 1990s. Its presence led to the decline of the native Duck Mussel, Anodonta anatina, its empty shells remaining at lake depths to 11 m. Dreissena polymorpha shells were recovered throughout the lake to depths over 30 m. The Asian Clam, Corbicula fluminea, was first recorded in Lough Derg in 2011 and has also extended its range beyond 30 m, although it was not found in the most southern region of the lake. The Quagga Mussel, Dreissena bugensis, first found in 2021, has locally displaced D. polymorpha. Exposed shells of all these species provide a settlement surface for byssal attachment and a change to sediment habitats, with their shells likely to provide refuges for other invertebrates.
Key words. Corbicula, Dreissena, benthos, introduced, local extinction, invasive species
Published 29 January 2026
DOI. https://doi.org/10.61733/jconch/4563
Daniel C. Cavallari & Rafael M. Rosa
Abstract. Numerous recent records on the citizen-science platform iNaturalist, initially identified by us as Drymaeus ribeiroi, prompted a re-evaluation of its taxonomic status and geographic range. A mid-western species from Brazil, D. ribeiroi was originally described as a subspecies of the poorly known Amazonian D. nigrogularis and later elevated to species rank without stated justification. We reassessed its status through examination of type material, additional museum specimens, and new photographic evidence. Our analysis shows that both nominal taxa are sympatric, share key diagnostic features, particularly the dark-brown pigmentation on the parietal peristome, supporting the treatment of ribeiroi as a junior synonym of nigrogularis. The iNaturalist records also expand the known distribution of the species across the southern and eastern margins of the Amazon rainforest. The observations of living individuals reveal a distinctly yellow head-foot with potential phylogenetic relevance. The occurrence of the species in both forested and urbanised habitats, and its prevalence within the Amazon “deforestation arc”, shows that improved sampling and assessment of its conservation status should be urgently undertaken.
Key words. Amazon, citizen science, Orthalicoidea, taxonomy
Published 30 January 2026
DOI. https://doi.org/10.61733/jconch/4564
First record of Melanoides tuberculata in Rhodes, Greece: a new invader or a failed introduction?
Konstantinos Kalaentzis, Gerasimos Kondylatos, Eleftherios Katsillis & Bernhard Hausdorf
Abstract. We report the first record of the freshwater snail Melanoides tuberculata on Rhodes Island, Greece. Empty shells were recorded in 2017 and 2021, followed by the observation of two live individuals in 2022, possibly indicating short-term survival and at least one overwintering event. Subsequent surveys revealed only shells, suggesting a transient or unsuccessful introduction rather than an established population. Seasonal hydrological instability may limit persistence. Continued monitoring is recommended.
Key words. Aegean, alien, non-native species, freshwater gastropods, aquarium trade
Published 1 February 2026
DOI. https://doi.org/10.61733/jconch/4565
Captain Thomas Brown (1785–1862): his life and molluscan taxa
Eugene V. Coan & Brian Goodwin
Abstract. A biography is provided for Captain Thomas Brown, who lived in Scotland and England, and is known to have visited Ireland and France. He chiefly made his living as a writer and publisher of popular natural history books, and eventually as a curator of the Manchester Museum. In malacology, he is most noted for two editions of a book on the Recent molluscs of the British Isles, one edition of a book on its fossil fauna, and a major paper on Carboniferous molluscs. Sadly, most of the types of his Recent species have been lost. Brown introduced 43 genera and 440 species, including unavailable names published in synonymies. Some genera are still in use. The species include 46% gastropods, 43% bivalves, 9% cephalopods, and 2% other classes. The species are 45% Recent, 23% Carboniferous, 10% Quaternary, 7% Jurassic, and 15% other epochs. We additionally list 13 taxa that have been misattributed to him. About a quarter of his taxa lack modern placements.
Here we designate Sipho striata T. Brown, 1827, to be the type species of Sipho T. Brown, 1827, affirming its place as a junior synonym of Puncturella R.T. Lowe, 1827. We designate Turbo graphicus T. Brown, 1818, as the type species of Pyramis T. Brown, 1827 [non Röding, 1798, nec Schumacher, 1817], ensuring its position as a junior synonym of Cingula J. Fleming, 1818. We designate Brochus striatus T. Brown, 1827, as the type species of Brochus T. Brown, 1827, ensuring its place as a synonym of Caecum J. Fleming, 1813. We designate Planaria alba T. Brown, 1827, as type species of Planaria T. Brown, 1827 [non Planaria O.F. Müller, 1776], fixing its position in the synonymy of Gyraulus Charpentier, 1837. We designate Cochlea virgata da Costa, 1778, as the type species of Heliomanes T. Brown, 1844 [non Newman, 1840], ensuring its placement as a synonym of Cernuella Schlüter, 1838. Naticopsis mazaevi Coan & Goodwin, 2026, is proposed as a replacement name for the Upper Permian Natica minima T. Brown, 1841, non I. Lea, 1833. Volutopsius golikovi Coan & Goodwin, 2026, is proposed as a replacement name for the Recent northwestern Pacific Fusus castaneus Mörch, 1848, non T. Brown, 1827.
Published 8 February 2026
DOI. https://doi.org/10.61733/jconch/4566
Li-Wen Lin & Ran-Xi Lin
Abstract. Two new Chinese camaenid species, Moellendorffia daner sp. nov. [儋耳多粒螺] from Hainan Province and Trichelix gengqii sp. nov. [耿齐绒粒螺] from Sichuan Province, are described in this paper. Photographs of the shells and the genitalia of these two new species are provided along with a distribution map of known Moellendorffia and Trichelix species from China and adjacent areas.
Key words. China, taxonomy, new species, anatomy, systematics
Published 8 February 2026
DOI. https://doi.org/10.61733/jconch/4567
Mihailo Vujić & Vukašin Gojšina
Abstract. Three species of the genus Gyraulus (Hygrophila: Planorbidae) are known to date as part of the Serbian fauna—G. acronicus (A. Férussac, 1807), G. albus (O.F. Müller, 1774), and G. parvus (Say, 1817)—with the last species reported exclusively under its junior synonym G. laevis (Alder, 1838). None of these species have been recognized as allochthonous in Serbian waters. Herein, we report on the occurrence of G. chinensis (Dunker, 1848) in Serbia for the first time, as well as on a morph of G. parvus with dark-pigmented tentacles, the allochthonous North American race of this species. We discuss the morphology and identification of these species, as well as the possible pathways of their introduction to Serbia. Both G. chinensis and the dark-tentacled morph of G. parvus are currently restricted to indoor and human-controlled waters in Serbia.
Key words. Allochthonous, aquarium, aquatic habitat, East Asia, greenhouse, Mollusca, North America
Published 25 February 2026
DOI. https://doi.org/10.61733/jconch/4568
Four new species of door snail from China (Gastropoda: Stylommatophora: Clausiliidae: Phaedusinae)
See also Correct original spelling of Probosciphaedusa gongjin Chen et al., 2026
Zhong-Guang Chen, Zhe-Yu Chen, Zhi-Jie Xu, Fan Li & Shan Li
Abstract. Four new species of Clausiliidae (Phaedusinae) are described from China, namely Atractophaedusa lui sp. nov. from Hunan, Euphaedusa qiuying sp. nov. and Probosciphaedusa gongjini sp. nov. from Hubei, and Synprosphyma xihuashida sp. nov. from Sichuan, based on comparative morphology. Atractophaedusa lui sp. nov. is most similar to A. takagii (H. Nordsieck, 2005), but it can be distinguished by its more slender shell, shallower palatal plicae, and the distant position of the peristome insertions. Euphaedusa qiuying sp. nov. is the first species of the genus with a dextral shell and can be distinguished from the congeners by the dextral, slender-fusiform, ribbed shell. Probosciphaedusa gongjini sp. nov. is the second species in its genus and can be distinguished from the type species by its more slender shell having more whorls and less prominent inferior and subcolumellar lamellae. Synprosphyma xihuashida sp. nov. is the first species of its genus with strong ribs and can be distinguished from its congeners by its small, ribbed shell with a straight lunella, which is separate from the lower palatal plica.
Key words. Taxonomy, land snails, clausiliids, new taxon, morphology
Published 12 March 2026
DOI. https://doi.org/10.61733/jconch/4569
Correct original spelling of Probosciphaedusa gongjin Chen et al., 2026
Zhe-Yu Chen & Zhong-Guang Chen
Published 17 March 2026
DOI. https://doi.org/10.61733/jconch/4570
Rodrigo B. Salvador, Emer Flanagan, Matthías S. Alfreðsson, Thomas G. A. Bawin, Joosep Sarapuu & Barbara M. Tomotani
Abstract. The Copse Snail, Arianta arbustorum (Linnaeus, 1758), is a common species in Europe, reaching from the Pyrenees in the south to the Arctic circle in northern Norway, and from the British Isles in the west to Russia in the east, with populations further afield in Iceland, Faroe Islands, and Canada. While its populations in Central Europe and the Alps have been widely studied, little is known about the Baltic coast and Nordic populations in Europe, including the Icelandic A. a. pseudorudis (Schlesch, 1924). We conducted a phylogeographic study focusing on the Baltic and Nordic populations of A. arbustorum, covering nearly all the species’ distribution, including individuals from all recognized subspecies. Our analysis showed the existence of a monophyletic Baltic/Nordic clade that represents a recent expansion front of the copse snail towards northern latitudes. Moreover, there were likely multiple introduction events in Iceland, and A. a. pseudorudis is considered a synonym of A. a. arbustorum. The type locality of A. arbustorum is restricted to Sweden, based on original literature and reassessment of syntypes. Arianta canigonensis (Boubée, 1833) is considered a separate species and has nomenclatural priority over A. xatartii (Farines, 1834), resulting in new combinations: A. canigonensis doriae (Paulucci, 1878) comb. nov., A. canigonensis gaillardi (Germain, 1912) comb. nov., A. canigonensis repellini (Reeve, 1852) comb. nov., A. canigonensis vareliensis (Ripken & Falkner, 2000) comb. nov., and A. canigonensis xatartii (Farines, 1834) comb. nov. Only three subspecies remain in A. arbustorum: the nominate A. a. arbustorum, A. a. stenzii (Rossmässler, 1835), and A. a. styriaca (Frauenfeld, 1868); the other subspecific taxa (alpicola, picea, pseudorudis) cannot be maintained as distinct subspecies and are synonymised with nominate arbustorum.
Supplemental Materials (https://doi.org/10.61733/jconch/4571s)
Key words. Phylogenetics, Pleistocene, poleward range expansion, population genetics, Stylommatophora
Published 23 March 2026
DOI. https://doi.org/10.61733/jconch/4571