No abstract available
A new species of Semiricinula, S. preturbinoides spec. nov. is described from the Langhian Middle Miocene of Java, Indonesia, as part of a series describing the assemblage found at Wonosari, and the presence of Taurasia striata (de Blainville, 1832) is recorded from these same beds.
Based on newly collected material, we describe a new species belonging to an unusual group of planispiral trigonostomid species, including also Pseudomalaxis boettgeri Cossmann, 1916, and erect the genus Rotatrigonostoma gen. nov. for these species.
An Iberian semi-slug, Drusia valenciennii (Webb & Van Beneden, 1836), was found in 2019 in the Netherlands. When this introduced species was first encountered, only photographs were taken, but a few juveniles were later collected; their raising to maturity is described. One mature specimen was dissected to examine the genitalia and confirm the identification. This is the first record of a Drusia species in northwestern Europe.
In this study, Truncatellina cylindrica (A. Férussac, 1807), Truncatellina rothi (Hesse, 1916), and Truncatellina haasi Venmans, 1957 were investigated, and a lectotype for Isthmia rothi was selected. So far, the three species have only been defined by their shell morphology. Intensified collection efforts throughout the past 100 years increased the number of specimens available, and it has become increasingly questionable whether these three species represent different taxa. In this study 1070 specimens were photographed, and measurements of several shell traits were taken. A multivariate ratio analysis revealed that the morphological trait variation of T. rothi (and probably T. haasi as well) is mainly covered by the variability of T. cylindrica. There is no morphological evidence that the investigated specimens represent different taxa. A genetic study is needed to reveal possible cryptic clades.
New data on the shell and the genital anatomy as well as on distribution and ecology of Eubrephulus peloponnesicus (E. Gittenberger, 1984) are presented. The morphology of genitalia and shell confirm the classification as Eubrephulus. Differences to the genera Chondrula and Mastus are discussed.
A new, isolated, population of the endemic Iberian hydrobiid Corbellaria celtiberica has been located, based on shells at the eastern foothills of the Iberian System (Province of Castellón, Valencian Community, Spain). The shells are biometrically studied and compared with shells from the type locality and with additional data from the literature. The finding of this new population considerably expands the previously known distribution area of the species.
A new species of Chicoreus (Triplex) is described from the Sudan in the Red Sea. It is compared with three closely related, allopatric species from the Red Sea: C. (T.) corrugatus (G.B. Sowerby ii, 1841); C. (T.) ethiopius Vokes, 1978; and C. (T.) teva Houart & Lorenz, 2016, as well as with C. (T.) strigatus (Reeve, 1849) and C. (T.) paini Houart, 1983 from the Indo-West Pacific. Chicoreus (Triplex) corrugatus ethiopius is here given the status of a valid species.
Collections in 2007 of 634 stations at 21 sites in northern Madagascar yielded 35 species and subspecies of rhytidoid land snails: Ampelita akoratsara akoratsara Emberton, 1999, A. akoratsara paulayi subspec. nov., A. analamerae Emberton, 1999, A. andavakoerae spec. nov., A. anjajaviensis spec. nov., A. atropos (Deshayes, 1850), A. capdambrae spec. nov., A. celestinae spec. nov., A. clotho (Deshayes, 1850), A. consanguinea (Deshayes, 1850), A. ela spec. nov., A. gaudens (Mabille, 1884), A. granulosa (Deshayes, 1850), A. kendrae spec. nov., A. kirae spec. nov., A. lachesis (Deshayes, 1850), A. lamarei lamarei (L. Pfeiffer, 1846), A. lamarei sakalava (Angas, 1878), A. lincolni spec. nov., A. masoalae Emberton, 1999, A. michellae spec. nov., A. miovaova spec. nov., A. niarae spec. nov., A. stilpna (Mabille, 1884), A. thompsoni spec. nov., Eurystyla ambatoensis (Emberton & Griffiths, 2009), E. julii julii (Fischer-Piette & Garreau, 1965), E. julii kely subspec. nov., E. julii soa (Emberton & Griffith, 2009), Paraclavator moreleti (Deshayes, 1851), Embertoniphanta amphibulima (L. Pfeiffer, 1847), E. echinophora (Deshayes, 1850), E. oviformis (Grateloup, 1840), E. josephinae spec. nov., and E. socii (Fischer-Piette, F. Blanc & Salvat, 1975).
Live adults of 17, and tissue samples of 22, of these 35 taxa were collected. The new species bring Madagascar’s total described rhytidoid species to 135. More await discovery, both within Madagascar’s forests and within extensive, unidentified collections from 1995-1996.
Discoveries include: (a) the hairy-shelled Embertoniphanta echinophora has a broad rainforest distribution and has an isolated, deciduous-forest, sister species, E. josephinae spec. nov.; (b) the gigantic (shell height 91.7 mm), micro-endemic Embertoniphanta socii is effectively absent from northern Ankarana; (c) the Eurystyla radiation is much more extensive than previously imagined; (d) southern Namoroka Reserve is not the home of its namesake Ampelita namerokoensis Fischer-Piette, 1952 (described from Bemaraha, far to the south!), but of A. thompsoni spec. nov.; (e) A. miovaova spec. nov., as proposed, is one of the most conchologically variable species of land snails; (f) A. lincolni spec. nov. is now the largest known Ampelita (73.5 mm diameter).
During the 2019 expedition of ‘Stichting Duik de Noordzee Schoon’ (DDNZS Foundation, or Dive to Clean the North Sea) several species were collected from ship wrecks that have not previously been recorded from the southern North Sea. A remarkably large specimen of Lamellaria latens (O.F. Müller, 1776) was found on the Queenford (40 km W of IJmuiden, The Netherlands) and juvenile specimens on the Ocean Prince and Inger Neilsen (Dogger Bank, United Kingdom). A juvenile specimen of Velutina plicatilis (O.F. Müller, 1776) was found on the St Luke (Dogger Bank, United Kingdom) and another on the U97 (105 km nw of Den Helder, The Netherlands). Over the last decade numerous species have been reported for the first time as autochthonous from wrecks in the Dutch part of the southern North Sea as a result of the ddnzs and other dive campaigns. They are part of the rich fauna living on hard substrates. As most are well known from the rocky shores of the British Isles it is likely that these species have previously been underreported due to sampling methods employed.
We present a history of the various collections of pelagic, or holoplanktic Mollusca, available in the Naturalis Biodiversity Center, Leiden The Netherlands. Both for the fossil and present-day collections numbers of available lots, stratigraphic and geographic origin and availability of type specimens are documented. We discuss four issues related to these collections: 1) preservation of pyritised fossils, 2) the backgrounds of the Maltese fossil collection material, 3) a list of all 505 taxa considered valid, 216 of which are currently living species (many of which also have a fossil record) and 4) diagnosis of Vaginellinae subfamily nov.
Since 1958 John van Aartsen had a keen interest in molluscs of the Mediterranean, and particularly the differences in malacofauna of the western and eastern parts of that basin. He focussed on Rissoidae, Pyramidellidae and bivalves; published 139 malacological papers and described 105, particularly minute-sized, species. Together with his wife Jozina, many trips were devoted to the collection of samples potentially containing small shell species. His collection with an odd 33,000 samples has been included in that of Naturalis Biodiversity Center (Leiden).
Type specimens of Polyplacophora present in the collections of the Nationaal Natuurhistorisch Museum, Leiden, formerly Rijksmuseum van Natuurlijke Historie (RMNH), and the Zoölogisch Museum Amsterdam (ZMA), now merged in the Naturalis Biodiversity Center, are listed. In total there is type material of 183 different species, consisting of 87 primary types (including 41 pro parte types) and 197 secondary type samples. On two plates are depicted the original coloured drawings of the newly described species by Nierstrasz (1905) published in ‘’Der Chitonen der Siboga Expedition’’. In addition an overview of all recent polyplacophoran species present in the two major molluscan collections in the Netherlands (Naturalis Biodiversity Center and Natuurhistorisch Museum Rotterdam (NMR)) is presented, including localities (country level) and number of samples. The history of the collections from both former RMNH, ZMA and NMR is summarized.