Gastropoda Systematics

The gastropod family Xenophoridae affix foreign objects to the shell surface. The objects include bivalve shells, smaller gastropod shells, shell fragments and encrusting corals. We identified gastropods attached on 100 shells of Xenophora pallidula (Reeve, 1842). We found that the buccinid Nassaria nivea (Gmelin, 1791), Bursa sp., the turrid Turricula javana (Linne, 1758) and the nassarid Bullia vittata (Linne, 1758) were the most common objects. Fragments and bivalve shells could not be identified.

Compiled and augmented by Christophe Avon Based on : « Freshwater Mollusk Bibliography » [02-26-2015] : 22,441 References, 1786 pp. "This freshwater mollusk bibliography database is a collaborative effort by Kevin Cummings, Illinois Natural History Survey, Art Bogan, North Carolina Museum of Natural Sciences, Tom Watters, The Ohio State University Museum of Biological Diversity, and Christine Mayer, Illinois Natural History Survey. The project was funded by the National Fish & Wildlife Foundation". Website : http://ellipse.inhs.uiuc.edu:591/mollusk/ http://www.WAS-Archives.org.

Identifying natural groups within the caenogastropod family Vermetidae has proven challenging. The sessile lifestyle of vermetids, with associated xenomorphically distorted, overgrown and corroded shells, has resulted in a long and confused taxonomic history based primarily on adult shell characters. In this study, we use morphological, anatomical and molecular data to clarify systematics and phylogenetic relationships within the genus Dendropoma s.l. We assess generic names previously used in the Dendropoma group for availability and recognize Veristoa Iredale, 1937, as a junior synonym of Dendropoma Mörch, 1861. We describe 21 species, eight of which are new, place them into four robustly supported genera (Dendropoma s.s.; Novastoa Finlay, 1926; Ceraesignum n. gen.; Cupolaconcha n. gen.), and outline the current state of knowledge of the distribution of these taxa. The genus Dendropoma s.s. is well supported in our phylogenetic analysis and is additionally supported by features of the operculum, reproductive traits and a novel mitochondrial gene order. Among the four genera, members of Dendropoma s.s. alone maintain unstalked egg capsules in the mantle cavity rather than attaching them to the shell via a slit in the female mantle. The opercula of examined species within the genus Novastoa are characterized by a well-developed mammilla on the internal surface and upright tightly packed spiral lamina on the external surface. In Ceraesignum n. gen., the operculum lacks a mammilla and displays a fingerprint-like texture on its inner surface. The genera Ceraesignum n. gen. and Novastoa form a well-supported monophyletic group with the genus Dendropoma s.s., although sister group relationships among these genera are not resolved. The fourth genus, Cupolaconcha n. gen. is more closely related to the vermetid genera Eualetes Keen, 1971a, Thylaeodus Mörch, 1860, and Petaloconchus Lea, 1843, demonstrating that Dendropoma s.l. is not a monophyletic group. The calcified operculum of Cupolaconcha n. gen. is unique in the Vermetidae and examined species in this genus are also characterized by a translocation of the valine mitochondrial tRNA. Further study will encompass the full range of morphological diversity in the Vermetidae to clarify the major lineages within this remarkable family of snails

In this paper, we describe a non-marine mollusk fauna deriving from late middle Miocene (late Serravallian; Sarmatian) deposits of western Serbia. The assemblage encompasses a diverse land snail fauna with twenty-four species, along with four species of freshwater pulmonate gastropods and one bivalve species. While the aquatic snails are ubiquitous elements in Europe during the middle Miocene, the terrestrial gastropod fauna, consisting of both common and rare species, offers the first comprehensive insight into land snail diversity on the Balkan Peninsula during that time and permits conclusions on regional biogeography. The fauna shows high affinities to the middle Miocene faunas of central Europe and shares only few elements with western and eastern European and Anatolian assemblages. Ecologically, the freshwater mollusks point to a standing or slowing moving, probably highly vegetated, lacustrine environment. The land snails indicate the presence of humid forests around Lake Vračević, which is in line with current climatic reconstruction for the Sarmatian of southeastern Europe. ?Vertigo vracevicensis Neubauer & Harzhauser sp. nov. and Pisidium mionicense Neubauer, Harzhauser & Mandic sp. nov. are introduced as new species. Discus costatus (Gottschick, 1911) is shown to be a junior objective synonym of Discus solarioides (Sandberger, 1872). •

Cowries (Cypraeidae) are diverse and occur in all tropical and some temperate seas, from shallow waters to the deep sea. There is a vast literature documenting the distribution, taxonomy, and shell variation, among many other topics. Because of its popularity among shell collectors, amateurs have contributed more to the cowrie literature than to most molluscan families. Traditionally, taxa have been described based on shell characters, and the majority of species descriptions continue to be published in non-peer-reviewed journals, magazines and books. Molecular studies in the last two decades have largely confirmed phylogenies based on morphology and anatomy. Currently, 245 species and 166 subspecies (or 411 operational taxonomic units) are recognized in 48 genera in the family. Despite being the best-known seashell family, the discovery curve suggests that there are still more taxa to be discovered. A review of the knowledge of the family is presented, and information on each genus is summarized.

The Pachychilidae comprises freshwater cerithioidean gastropods with a pantropical distribution that extends from Central to South America, Africa and Madagascar to Australasia. Traditionally treated as members of the so-called “Melaniidae” or Thiaridae sensu lato, they have a confusing taxonomic history, and, in addition, their phylogeny is still not completely resolved. Currently, the systematics of the Southeast Asian pachychilid taxa, in particular species of the widespread Brotia A. Adams, 1866 sensu lato, is under revision. In addition to this ongoing work, the present paper briefly summarises the taxonomic history of the Pachychilidae, catalogues the described pachychilid genera, species and subspecies known from Southeast Asia, and documents their relevant type material located in various museum collections world-wide. Excluded from this list are those Brotia taxa endemic to Sulawesi, which will be treated separately. In total, 124 nominal species and subspecies are identified here, which can be attributed to the Pachychilidae by diagnostic characteristics of their shell, operculum, radula, and, if available, by their soft body anatomy. In addition to those in the Malacological collection of the Berlin Natural History Museum several types from various other museum collections are included here, which were not always recognized previously as types. In order to stabilise the taxonomy, we herein designate 48 lectotypes. When necessary, comments on systematics, taxonomy or further references are added. The taxonomic status of several species is changed and indicated accordingly.

In this paper current knowledge on the diversity of the gastropod
cephalaspidean genus Haminoea from India is revised. A comprehensive
literature review was undertaken and novel specimens were
collected. Specimens from India were DNA barcoded using the gene
cytochrome c oxidase sub-unit I and a Bayesian gene tree together
with an Automatic Barcode Gap Discovery (ABGD) species delimitation
analysis were inferred to compare Indian samples with species
from the Indo-West Pacific. The most comprehensive DNA data set to
date of the genus Haminoea is included and new morpho-anatomical
features of Indo-West Pacific species were generated through fine
anatomical work and scanning electron microscopy. A critical appraisal
of previous records of the country is included and a new species,
Haminoea aptei sp. nov., is described from the Andaman Islands and
Lakshadweep Islands, India.

The identity of Turbo bryereus Montagu is established after examining the original, figured type-specimen. It is considered a valid species of Schwartziella (Rissoidae: Rissoininae) from the West Indies. Rlsoina scalarella C.B. Adams, R. bermudensis Peile and R. fischeri var.
michaudi Desjardin are considered junior synonyms . " R. bryeea" auctt. is described as new s.n. Rissoina dyscrila n.sp.

The present paper details a very diverse non-marine gastropod fauna retrieved from Caspian Pleistocene deposits along the Volga River north of Astrakhan (Russia). During time of deposition (early Late Pleistocene, late Khazarian regional substage), the area was situated in shallow water of the greatly expanded Caspian Sea. The fauna contains 24 species, of which 16 are endemic to the Pontocaspian region and 15 to the Caspian Sea. The majority of the species (13) belongs to the Pyrgulinae (Hydrobiidae), a group famous for its huge morphological variability in the Pontocaspian region. The phenotypic diversity has led to an inflation of genus and species names in the literature. New concepts are proposed for many of the genera and species found in the present material, with implications for the systematics and taxonomy of the entire Pontocaspian gastropod fauna. Laevicaspia vinarskii sp. n. is described as a new species. This contribution is considered a first step in revising the Pontocaspian gastropod fauna.

The family Eulimidae comprises minute gastropods best known for its parasitic habit on Echinodermata. Despite this, reports of association between eulimids and echinoderms are rather scarce. In this study, two new hosts, Parathyone suspecta and Holothuria grisea, were observed for the eulimid Melanella eburnea. This is the first record for the latter species in Brazilian waters. In addition we observed the association between the eulimid M. hypsela and the holuthurian Isostichopus badionotus, which is a new record for Brazilian waters.

The ‘scaly-foot gastropod’ is widely recognized as an iconic species of deep-sea hydrothermal vent ecosystems in the Indian Ocean. Uniquely among gastropods, this species carries hundreds of dermal sclerites on its foot and these scales can be covered in iron sulphide that also covers its shell, making it the only extant metazoan known to utilize iron sulphide as part of its skeleton. It has not been formally named, despite attracting great attention from both scientists and the general public alike, although a manuscript name has occasionally been used in various sources. The RRS James Cook JC67 expedition in 2011 sampled the biota of the Longqi vent field (37°47.027′S, 49°38.963′E), Southwest Indian Ridge, for the first time, revealing a previously unknown population of the ‘scaly-foot gastropod’. The present study gives a formal name to the ‘scaly-foot gastropod’, Chrysomallon squamiferum n. gen., n. sp. with Longqi vent field as the type locality. The erection of the new monotypic genus is supported by both morphological and molecular characterization, differentiating it from existing genera of the family Peltospiridae. Analysis of the cytochrome c oxidase subunit I gene reveals a 24–26% pairwise distance between Chrysomallon and five other genera of Peltospiridae, while the range among those five genera is 14–25%. The new genus is placed in the family Peltospiridae based on morphological characteristics, including lack of sexual dimorphism, no copulatory organ, the distal end of marginal teeth being subdivided into many denticles and the ventral margin of the gill leaflets carrying a series of bulges. A five-gene Bayesian phylogenetic reconstruction does not contradict the placement within Peltospiridae.

New samples of freshwater molluscs collected by the second author in the East Mediterranean region of Turkey
revealed three new species of the genus Pseudamnicola Paulucci, 1878, i.e., P. goksunensis n. sp., P. merali n. sp., and
P. marashi n. sp. Descriptions and photos of the species as well as the type localities are presented.

The Paleocene gastropod species described as Trochus alabamensis Aldrich, 1886 has long been considered a member of the vetigastropod genus Solariella. Newly collected material from Mississippi’s Matthews Landing Marl Member of the Porters Creek Formation (Late Paleocene: Selandian) with well preserved anastrophic protoconchs provides evidence that this species belongs to the Heterostropha/ Heterobranchia. A redescription is provided and a discussion of its characters leads to placement in the family Mathildidae. A new genus,Toulminella Bieler & Dockery, is introduced for it.

The bulimulid genus Bostryx Troschel, 1847 is the most species-rich genus of land snails found in Chile, with the majority of its species found only in the northern part of the country, usually in arid coastal zones. This genus has been sparsely studied in
Chile and there is little information on their distribution, diversity or ecology. Here, for the first time, a formal analysis of the diversity of bulimulids in the Región de Atacama, northern Chile, is reported. Of the seventeen species recorded for the area, most of them were effectively found in the field collections and one record was based on literature. Five taxa are described as new: Bostryx ancavilorum sp. nov., Bostryx
breurei sp. nov., Bostryx calderaensis sp. nov., Bostryx ireneae sp. nov. and Bostryx valdovinosi sp. nov., and the known geographic distribution of seven species is extended. Results reveal that the Región de Atacama is the richest region in terrestrial snails in Chile, after the Juan Fernández Archipelago. All of the terrestrial molluscan species occurring in the area are endemic to Chile, most of them with restricted geographic distributions along the coastal zones, and none of them are currently protected by law. Further sampling in northern Chile will probably reveal more snail species to be discovered and described.

"The Phoenix talussnail is remarkable for its ability to live in the hot, dry hills of the Sonoran Desert. It occurs in northeastern Maricopa County within the greater Phoenix metropolitan area from Piestewa Peak north to the town of New River, and from the McDowell Mountains west to New River. The species is known from 25 locations."

Evolution of views on the family Ceritellidae, which actually after their erection were considered as nerineas, taking the key position within the latter group, has been reviewed. Ceritellidae was positioned as a group of most primitive and commonly unplicated nerineas, ancestral for most nerineids. Later the basic morphological features of nerineas were reconsidered. Data on morphology of ceritellid genera, summarized from numerous literature sources, demonstrate that only some genera can be interpreted as true nerineas. Heterostrophy of the shell is the single feature, common for both taxa, so only Fibula and Sequania have a selenizone and shell construction as in nerineas. Systematical position of other genera needs to be revised. Ceritella and Ceritellopsis are certain representatives of Acteonoidea, therefore family Ceritellidae cannot to be placed among nerineids. Proceritella has to moved into Trochidae, while Terebrella and Gymnocerithium have to be placed in Cerithioidea.

Background: The Atlantic Forest is globally one of the priority ecoregions for biodiversity conservation. In Argentina, it is represented by the Paranense Forest, which covers a vast area of Misiones Province between the Paraná and Uruguay rivers. The Uruguay River is a global hotspot of freshwater gastropod diversity, here mainly represented by Tateidae (genus Potamolithus) and to a lesser extent Chilinidae. The family Chilinidae (Gastropoda, Hygrophila) includes 21 species currently recorded in Argentina, and three species in the Uruguay River. The species of Chilinidae occur in quite different types of habitats, but generally in clean oxygenated water recording variable temperature ranges. Highly oxygenated freshwater environments (waterfalls and rapids) are the most vulnerable continental environments. We provide here novel information on three new species of Chilinidae from environments containing waterfalls and rapids in the Uruguay River malacological province of Argentina. Materials and Methods: The specimens were collected in 2010. We analyzed shell, radula, and nervous and reproductive systems, and determined the molecular genetics. The genetic distance was calculated for two mitochondrial markers (cytochrome c oxidase subunit I–COI-and cytochrome b-Cyt b-) for these three new species and the species recorded from the Misionerean, Uruguay River and Lower Paraná-Río de la Plata malacological provinces. In addition, the COI data were analyzed phylogenetically by the neighbor-joining and Bayesian inference techniques. Results: The species described here are different in terms of shell, radula and nervous and reproductive systems, mostly based on the sculpture of the penis sheath. Phylogenetic analyses grouped the three new species with those present in the Lower Paraná-Río de la Plata and Uruguay River malacological provinces. Discussion: Phylogenetic analyses confirm the separation between the Uruguay River and the Misionerean malacological provinces in northeast Argentina. These new endemic species from the Uruguay River add further support to the suggestion that this river is a diversity hotspot of freshwater gastropods (with 54 species present in this basin, 15 of them endemic). These endemic species from environments with rapids and waterfalls should be taken into account by government agencies before the construction of dams that modify those ecologic niches in the Uruguay River.

We describe a new fossil littorinid species, Echinolittorina nielseni sp. nov., from the Quaternary Caldera Strata, Región de Atacama, northern Chile. Fossils of littorinids are globally rare because of their high-intertidal habitat on rocky shores. The new species has a large, broad shell with strong spiral ribs and an angled periphery, differing from the two living littorinids currently found along the coasts of mainland Chile and from all the extant species distributed in the southeastern Pacific. In comparison with the living Chilean Echinolittorina peruviana, the new species shows stronger ribs and more inflated whorls, but they share an unusual detail in the irregular arrangement of spiral sculpture. We hypothesize that the new species may be ancestral or sister to E.peruviana and discuss the adaptive significance of shell sculpture.

The coast of northern Chile has been sparsely studied in regards to its invertebrate fauna, with just a few works reviewing the distribution of local mollusks. This work presents a survey of the shallow water heterobranch sea slugs currently occurring around the port of Caldera (27 S), in the Regió n de Atacama, northern Chile.

During the KARUBENTHOS I expedition to the tropical western Atlantic island Guadeloupe, May 2012, an unknown species of Pyramidellidae was collected which resembles members of the rissoinid genus Zebinella in many details. Both a new species and genus are introduced, and possible explanations for this phenomenon are discussed.
Key words: Mollusca, Gastropoda, Pyramidellidae, Rissoinidae, Caribbean, West Indies, Guadeloupe.

Recently discovered hydrothermal vent fields on the East Scotia Ridge (ESR, 56–60°S, 30°W), Southern Ocean, and the South West Indian Ridge (SWIR, 37°S 49°E), Indian Ocean, host two closely related new species of peltospirid gastropods. Morphological and molecular (mitochondrial cytochrome c oxidase subunit I, COI) characterization justify the erection of Gigantopelta gen. nov. within the Peltospiroidae with two new species, Gigantopelta chessoia sp. nov. from ESR and Gigantopelta aegis sp. nov. from SWIR. They attain an extremely large size for the clade Neomphalina, reaching 45.7 mm in shell diameter. The oesophageal gland of both species is markedly enlarged. Gigantopelta aegis has a thick sulphide coating on both the shell and the operculum of unknown function. The analysis of a 579-bp fragment of the COI gene resulted in 19–28% pairwise distance between Gigantopelta and six other genera in Peltospiridae, whereas the range amongst those six genera was 12–28%. The COI divergence between the two newly described species of Gigantopelta was 4.43%. Population genetics analyses using COI (370 bp) of 30 individuals of each species confirmed their genetic isolation and indicate recent rapid demographic expansion in both species.