Aydin Örstan

• Ph.D.
• Research Associate at Carnegie Museum Of Natural History

The European land snail Cepaea nemoralis was introduced into Burlington, New Jersey, USA by William G. Binney in 1857 with specimens from near Sheffield, England. First in 1869 and later in 1878, Binney noted that the species had become widespread throughout the city. Between 1908 and 1933, Henry A. Pilsbry collected a large number of C. nemoralis...

A survey was carried out to determine the distribution range of Cochlostoma mienisi Schütt, 1978, a little studied land snail of southwestern Turkey. The species was found on the island of Kekova off the coast of Turkey and at an additional location on the mainland facing the island. The closest congeners of C. mienisi are on Crete and mainland Gre...

Thirty-three species of land snails were collected during a survey of the calcareous areas of the Karaburun Peninsula in western Turkey. The first record of Pagodulina hauseri for Turkey is given. Also given is the first record outside of Chios of a specimen identified tentatively as Vitrea storchi. Anatomies of Microxeromagna lowei, Monacha ocella...

China is one of the most biodiverse countries worldwide, with a variety of landforms and climatic conditions. However, the diversity and biogeographic distribution of bdelloid rotifers, one of the most widespread microscopic organisms worldwide, have received little attention in China. In order to understand the species diversity of bdelloid rotife...

The survey of the freshwater snails in the Potomac River that started in the fall of 2023 was continued in 2024. Three species, Cipangopaludina cf. japonica, Gillia altilis and Laevapex fuscus, have been added to the list of species recorded during the survey. Results The survey was done between 29 April and 25 November 2024. The locations surveyed...

The brachiopod Argyrotheca cuneata (Brachiopoda: Megathyrididae) is reported for the first time from the southern coast of Türkiye. Twenty-three complete specimens were found in samples of shell grit taken from depths less than 5 m. The findings suggest that A. cuneata may be a common brachiopod species in shallow nearshore habitats along the south...

We report the finding of the Lessepsian migrant Coriophora lessepsiana Albano, Bakker & Sabelli, 2021 at the western shore of the Gulf of Antalya at the southern coast of Türkiye in October 2022. The species was collected in the Mediterranean for the first time at the Israeli coast in 2018. The present record is the first from the Turkish coasts an...

Land snails exhibit an extraordinary variety of shell shapes. The way shells are constructed underlie biological and mechanical constraints that vary across gastropod clades. Here, we quantify shell geometry of the two largest groups, Stylommatophora and Cyclophoroidea, to assess the potential causes for variation in shell shape and its relative fr...

A survey of the freshwater snails in the Potomac River was carried out in the fall of 2023. Elimia virginica and Leptoxis carinata were the most commonly observed larger snail species. Cincinnatia integra was found in the Potomac River for the first time in nearly 100 years.

Six small rock pools were studied to determine the taxonomic diversity of bdelloid rotifers inhabiting them. The most frequently found bdelloids in rock pools belonged to the bottom-feeding genus Adineta and the suspension-feeding genera Otostephanos and Philodina. To explain the coexistence of multiple bdelloid species in small rock pools two proc...

We discuss the distributions and conchological characteristics of 7 Albinaria taxa present in calcareous areas around the coastal town of Marmaris in southwestern Türkiye. A new subspecies, Albinaria coa tek Örstan is described from a disjunct population found on a small island south of Marmaris. The new subspecies is geographically closest to A. b...

The coastal snail Pirenella conica (Gastropoda: Potamididae) was observed and photographed in its mud flat habitat (Alaçati Bay, Karaburun Peninsula, Türkiye) and in the laboratory. The snails were amphibious; they moved about in damp sediment when the sea had receded and readily left the water in the laboratory to move on dry surfaces. The siphon,...

The Southeast Asian genus Angustopila, currently comprising 13 nominal species, encompasses the world’s tiniest land snails. This work shows that there are far more species than previously suspected, and that this genus is in fact a very speciose group of tiny snails widely distributed in Southeast Asia. Angustopila is revised based on type materia...

Two relatively rare Mediterranean gastropods, Cima cylindrica and Cima minima (family Cimidae) have been found in samples collected near the shore at Phaselis. These are the first records of these species from the coasts of Türkiye.

A land snail from an altitude of 2300 m on Tahtalı Mountain in southern Türkiye is described as a new species, Metafruticicola diva Örstan & Yıldırım spec. nov. The new species is distinguished from the previously known high-altitude Metafruticicola species by its unbanded shell with short hairs and anatomical characteristics.

A new species of bdelloid rotifer, Philodina monstrosa sp. nov. (Rotifera: Bdelloidea: Philodinidae), is described. Philodina monstrosa is a large carnivore exceeding 1000 µm in length that feeds on live and dead rotifers. The habitat of the rotifer is a birdbath in Maryland, U.S.A. This finding brings attention to the presence of undiscovered biod...

A survey of the land snails of Bozcaada, a small island in the Aegean Sea near the northwest coast of Turkey, found 30 species. Mediterranea depressa (Sterki) was recorded for the first time in Turkey. Five species in the family Enidae were found on the island; the most unexpected one was Chondrus tournefortianus (Férussac) outside of its previousl...

A survey conducted during the years 2019 and 2021 in Phaselis found 22 species of snails and one species of semi-slug. The most abundant taxa were Albinaria lycica phaselis, Metafruticicola schuberti, Orculella ignorata and Rumina saharica. The scarcity of larger snails (Cornu, Eobania and Zonites species) was noteworthy. The anatomy of a specimen...

Two new, extremely small land snail species, Angustopila coprologos Páll-Gergely, Jochum & Hunyadi n. sp. and Angustopila psammion Páll-Gergely, Vermeulen & Anker n. sp. are described from northern Vietnam and northern Laos, respectively. The former is characterized by a rough surface sculpture and bears tiny mud granules arranged in a pattern of r...

An account of the butterfly Red-spotted Purple Limenitis arthemis puddling on dung is presented.

This is the pdf version of a Zoom presentation given on behalf of the Natural History Society of Maryland on 14 October 2021. It starts with a brief introduction to slug biology. Next the most common slug species present in Maryland, USA are discussed. The native genera include Megapallifera, Pallifera and Philomycus, while among the introduced spe...

The discovery and the description of the bdelloid rotifer Coronistomus impossibilis are summarized. This is followed by a discussion of some of the problems that stymie taxonomical research in bdelloids.

A new bdelloid rotifer, Coronistomus impossibilis gen. nov., sp. nov. is described from the Hawlings River in Maryland, USA. The new species is a non-swimming sediment dweller that exceeds 550 µm in body length. Its corona is a weakly bilobed ciliated field on the ventral side of the head with lateral borders continuing into mouth. The species has...

Taxonomically significant morphological, behavioral and ecological traits of bdelloid rotifers in the family Philodinidae are discussed. It is recommended that new morphospecies descriptions include information on all of these traits.

My purpose here is to highlight three long-standing problems in the taxonomy of Adineta vaga (Davis, 1873) and its subspecies: 1. The lack of unique morphological criteria to identify the morphological variant (morphovariant) Davis described; 2. The lack of an evolutionarily meaningful subspecies definition applicable to parthenogenetic bdelloid ro...

A land snail extracted from rotting wood in a pine forest at an altitude of 1350 m on the noncalcareous Sandras Mountain in western Turkey is described as a new species, Mediterranea xylocola Örstan spec. nov. Besides its unusual habitat, the new species is also characterized by its small shell (~4 mm in diameter) microsculptured with distinct spir...

The distribution records of Albinaria species along the southwestern coast of Turkey and the identity of the specimens collected near its type locality indicate that Clausilia (Albinaria) luschani E. von Martens, 1889 is a junior synonym of A. anatolica (Roth, 1839). Basteria 83 (4-6): 131-132. Published 9 November 2019

The genera Aulacospira and Pseudostreptaxis of the Philippines are revised based on the collections of the Senckenberg Forschungsinstitut und Naturmuseum (Frankfurt am Main, Germany), the Florida Museum of Natural History (USA), and recently collected material. Three new species are described: Aulacospira lens Páll-Gergely & Auffenberg, sp. n., Aul...

The genera Aulacospira and Pseudostreptaxis of the Philippines are revised based on the collections of the

The range of Albinaria latelamellaris Neubert, 2000 has been found to cover an area only about 10 hectares around its type locality in southwestern Turkey. A new subspecies, Albinaria latelamellaris kekovensis subspec. nov., is described from a disjunct population about 9 km away in the coastal Kekova region. The shells of the new subspecies differ...

The morphological descriptions of the species of bdelloid rotifers and the associated taxonomic difficulties, primarily resulting from the inadequate original descriptions of many species, are discussed. The genus Adineta, whose members are relatively easy to study and frequently encountered, is proposed as a starting point for taxonomic revisions...

The distribution of the mean greater shell dimensions of 2446 genera of stylommatophoran land snails consists of two groups peaking at 3 mm and 15.3 mm. The 3-mm group includes the miniature snails whose adult shell dimensions range from almost 0.8 mm to less than 1.5 mm. Relative surface area, shell thickness and egg size are discussed as potentia...

We present an annotated list of the more than 40 bdelloid taxa that have been described since the publication of Josef Donner's Ordnung Bdelloidea in 1965. Additionally, a Habrotrocha specimen that was misidentified in the literature is designated here to be a new species.

This study compared the growths of the foot and the shell of the clausiliid snail Euxina circumdata during its ontogeny. Also monitored was how the snails carried their shells in apparent conformity with the changes in the relative dimensions of their shells and feet. In juvenile snails foot lengths were comparable to shell lengths, but the feet st...

A captive individual of Pomatias elegans was able to repair an opening at the edge of the aperture of its shell. I have reported (Örstan, 2005a) the presence of scars of repaired breaks on the shells of the land snail Pomatias elegans (Müller). Now I present the results of a shell repair test done with a live specimen of the same species. One adult...

Comparison of the shells of a land snail collected in Montreal, Canada with those of several North American and European Discus species resulted in the identification of the Montreal specimens as the European Discus rotundatus.

A significant difference was obtained between the mean shell lengths of two samples of Batillaria minima measured two years apart at a location in Florida. Some phenomena potentially responsible for the observed difference are discussed.

This paper describes a method to determine the volume of a snail shell from the weight of the water displaced by the shell. The volume of a snail shell signifies the amount of housing space the occupant snail needs. This significance holds even if the snail's body fills a portion of the inner space of its shell, leaving aside the rest for other fun...

Seven species of land snails and one semi-terrestrial snail were found at the Ottoman fort in the village of Rumelifeneri at the entrance to the Bosphorus from the Black Sea. Discus rotundatus was recorded for the second time in Turkey.

I studied the reproduction and the population turnover of a succineid land snail living by a small lake in central Maryland. The identity of the snail, deduced from its external characteristics and the genitalia, comes closest to Oxyloma retusum (Lea, 1834). The species has a semelparous life cycle. The snails that survive the winter grow and repro...

The European land snail Cepaea nemoralis (Linnaeus, 1758) was introduced in North America in 1857 inBurlington, New Jersey, U.S.A. There is only one anedoctal record of C. nemoralis from Montreal, Canada, but without a dateor an exact location. In this note, recent records of C. nemoralis are presented for Montreal, based on surveys from 7 to 9Augu...

A specimen of Vertigo pusilla from the Kastamonu province of Turkey is the third record of the species for the country.

When Pedipes ovalis withdraws into its shell, its foot is se-questered between the parietal and the columellar teeth, while the sinus above the parietal tooth encloses the portion of the mantle skirt with the pneumostome. This organization suggests that one function of the long parietal tooth characteristic of the genus is to prevent the snail's fo...

A live thrips was photographed inside an empty shell of the land snail Zonitoides arboreus. The insect seemed to have been using the shell as a shelter.

The land snail Anguispira fergusoni is a newly recorded prey for the parasitoid larva of the sciomyzid fly Pherbellia albovaria.

Twenty-one native species of land snails were recorded during a survey of the Aydin Mountains in the Province of Aydin, Turkey. Idyla aydinensis Örstan (Pulmonata: Clausiliidae) is described as a new species from an altitude of 1030 m. The new species is characterized by a narrow shell with closely spaced fine ribs and a long penis with a grooved p...

Turkish specimens of Xerocrassa cretica are compared with specimens from the Greek islands of Karpathos and Kasos. Turkish specimens have larger and higher shells and differ in the proportions of some parts of their genitalia.

The holotype of Sprattia sowerbyana aksoylari was recently deposited in the Carnegie Museum of Natural History in Pittsburgh, Pennsylvania, U.S.A. A brief re-description of the holotype is also given. Sprattia sowerbyana aksoylari was given full species rank i.e. Sprattia aksoylari by Nordsieck (2004).

The intertidal snail Batillaria minima can withdraw its body into its shell at least a quarter of a whorl away from the aperture of its shell. Shells with repair scars in the last quarter turn of the body whorl indicate that the retractibility of the snail protects it from predatory attacks. An effective defense mechanism in gastropods is the retra...

Records of Papillifera bidens (Linnaeus, 1758) from various locations around Istanbul based on collections done in the early 2000s.

Diversidad de los caracoles terrestres en una zona caliza amenazada cercana a Estambul, Turquía.¿ Las praderas calcáreas situadas al NNO de Estambul están en peligro de ser rápidamente invadidas por la ciudad en expansión. Estudios anteriores demostraron que estos hábitats albergan especies vegetales raras, incluyendo algunos endemismos turcos. Con...

Fifty species of land snails, (38 native, 12 introduced), were collected during a survey of the Bodrum peninsula, Turkey. Collections were also done on the Turkish island Kara Ada off the coast of Bodrum and the more distant Greek islands, Kalimnos and Psérimos. Pyramidula chorismenostoma and Vitrea sossellai are recorded for the first time in Turke...

Contrary to a claim in the literature, scars on the shells of Pomatias elegans demonstrate that this species can repair its shell.

Three new disjunct records of the land snail Levantina spiriplana from western Turkey are given. One record is from an antique city and the other two are from inland areas that had access to the Aegean in the antiquity. The distribution pattern suggests that the species was introduced to these locations by humans.

Borlumastus gen. nov. is described as a new genus of the family Enidae and compared concho-logically and as regards the genitalia with similar genera. The new genus is characterized by an elongated shell with only a palatal tooth in its aperture, an S-shaped penile verge, longitudinal folds covering the inside walls of the penis and by the lack of...