Journal of Conchology 43 (3), April 2019

ISSN 2755-3531

 

Is Limax cinereoniger Wolf, 1803, present in Italy? An anatomical approach to the study of Italian Limax (Gastropoda: Pulmonata: Limacidae)

Marco Bodon, Gianbattista Nardi, Simone Cianfanelli, Stefano Birindelli & Ivano Niero

Abstract. An anatomical approach to the study of the slugs belonging to the genus Limax, based on the structures present in the inner walls of the penis, is proposed. These characteristics clearly allow the separation of the different species and they agree with the results obtained in genetic investigations. In this first contribution many populations of L. cinereoniger are reported from the north-eastern area of Italy (Veneto, Trentino-Alto Adige and Friuli-Venezia Giulia) and compared with other European populations. The diagnostic characters of L. cinereoniger, such as the sole colour (blackish lateral bands), the comparatively elongate penis (42–159 mm), first crest much longer than the second one and the low and very short second crest and pleat are discussed and compared with those of similar species.

Key words. Limax cinereoniger, genital anatomy, Europe, Italy

Date of publication. April 2019

 

Intraspecific morphological and genetic variability in the Palaearctic freshwater snail Radix ampla (Hartmann, 1821) (Gastropoda: Basommatophora: Lymnaeidae)

Katrin Schniebs, Peter Glöer, Maxim V. Vinarski, Luboš Beran & Anna K. Hundsdoerfer

Abstract. Radix ampla (Hartmann, 1821) is a widely distributed Palaearctic freshwater snail with a still insufficiently known distribution. This work aims to improve the knowledge of the intraspecific variability in the most important characters used for its determination. To find out which characters are really suitable to distinguish this species from other similar Radix species, an integrative approach was applied, involving morphological and molecular data (including sequences from six outgroup Radix species). Molecular sequences of the nuclear spacer fragment ITS-2 and the mitochondrial gene fragment cyt–b were obtained from 30 individuals of R. ampla as well as from eight individuals of R. monnardi (Hartmann, 1841) from different regions of Europe and Western Siberia. From the subsample of 36 specimens the variability of several characters that are commonly used for species identification (shell morphology, mantle pigmentation, shape and position of the bursa copulatrix, length and position of the bursa duct, length ratio of praeputium to penial sheath) were found to be broader than recognised in current literature. The differentiation of atypical R. ampla from R. balthica (Linnaeus, 1758) and R. lagotis (Schrank, 1803) using morphological characters only, was very difficult. R. monnardi and R. hartmanni (Hartmann, 1821) proved to be junior synonyms of R. ampla.

Key words. Freshwater gastropods, molecular genetics, morphology, Radix ampla, variation

Date of publication. April 2019

 

A Liburnica species from southern Italy (Gastropoda: Pulmonata: Helicidae)

Abstract. A species of the ariantine helicid genus Liburnica is reported for the first time from southern Italy. It is very similar to Liburnica setosa, the type species of the genus, in shell and anatomical features (namely: continuous detached peristome; occasional small faint denticle in basal peristome; penial papilla with lateral slit-like pore almost as long as the papilla itself; digitiform glands that branch at ca. 1/3 of their length). A potential name for this species is Helix setulosa Briganti, 1825 from a site (Salvitelle) very close to where it was collected (Gole del Fiume Platano). Briganti’s figures are not very clear, but they depict shells with a continuous peristome, angled at its innermost point, as in Liburnica species. Unfortunately, no sure syntypes and no topotypes were available and more research is therefore necessary to verify this hypothesis. From a biogeographical point of view, the finding of the genus Liburnica in southern Italy is interesting because it constitutes another case of a taxon with significant disjunct distribution involving Apennine Italy and the Balkan Peninsula.

Key words. Land snails, Mediterranean, anatomy, taxonomy, biogeography

Date of publication. April 2019

 

A new species of the genus Diodora Gray, 1821 (Gastropoda, Fissurellidae) from the Cabo Verde Islands

Keider Neves, Sara Castillo & Fran Ramil

Abstract. A new species is described, Diodora terezae, from off Boavista Island (Cabo Verde Archipelago) collected during the CCLME-FAO ecosystemic survey CAPVERT-1106 at a depth of 92–98 m. This new species is characterised by the presence of 70 flattened primary axial ribs, absence of secondary riblets in the interspaces, and numerous, evenly spaced, undulated concentric cords. The main differences between Diodora terezae n. sp., and those species previously reported from the Cabo Verde Islands or elsewhere are discussed. A table summarising the main morphological features, geographical distribution, depth range, and main references for all the species discussed in this paper is also provided.

Key words. Gastropoda, Fissurellidae, Diodora, new species, Cabo Verde Islands, Northwest Africa

New taxon. Diodora terezae Neves & Ramil, 2019

Date of publication. April 2019

 

A species comes of age: new material and micro-CT scanning reveal the adult of Gulella bicarinata Blume from Kilimanjaro, Tanzania; with a discussion of Mirellia Thiele from Kenya (Pulmonata: Streptaxidae)

Ben Rowson, Werner de Gier & A.J. (Ton) de Winter

Abstract. Gulella (Paucidentina) bicarinata Blume, 1965 was described from a damaged, immature shell. New topotypic material from Kilimanjaro, Tanzania includes adults which are here described with the aid of micro-CT scans of the unusual shell. The shell and anatomy of adults show similarities with the little-known central Kenyan taxon Mirellia Thiele, whose sole species Ennea prodigiosa E.A. Smith, 1903 is also scanned and dissected. Most workers have treated Mirellia either as a subgenus of Gulella L. Pfeiffer, or as a subgenus of Ptychotrema L. Pfeiffer. These alternatives are discussed and both species are assigned to Mirellia, which is here treated as a genus in its own right. 

Key words. Hunter snails, East Africa, taxonomy, snails, radula, shells, genitalia, anatomy

Date of publication. April 2019

 

Nassarius maxiutongi, a new species of Nassariidae (Mollusca, Neogastropoda) from the South China Sea

Shuqian Zhang, 2, Suping Zhang & Haitao Li

Abstract. A new nassariid species collected from Lingshui Bay of Hainan Island in the South China Sea is described and assigned to the genus Nassarius Duméril, 1805. This new species, Nassarius maxiutongi sp. nov., has a medium sized shell with a small, acute spire; spiral sculpture present on earlier teleoconch whorls but becoming reduced and absent on lower part of the penultimate and upper part of the last whorl. Each rachidian tooth bears 13 or 14 cusps in the male and 16 or 17 in the female specimen. These features can be used to distinguish the new species from its congeners.

Key words. Nassariidae, new species, China

New taxon. Nassarius maxiutongi Zhang, Zhang & Li, 2019

Date of publication. April 2019

 

New taxa and distribution data of Clausiliidae (Gastropoda: Pulmonata) from karst regions of Southeast Asia

Duc Sang Do, Jozef Grego & Miklós Szekeres

Abstract. Recently obtained mollusc samples provided valuable new information on the Clausiliidae of Laos, Vietnam, and China’s Yunnan Province. Grandinenia dautzenbergi abdoui Grego & Szekeres subsp. nov., Grandinenia muratovi Grego & Szekeres sp. nov., Oospira duci smidai Grego & Szekeres subsp. nov., Phaedusa micropaviei hmongorum Grego & Szekeres subsp. nov., Synprosphyma phuonganhae Do & Szekeres sp. nov., and Synprosphyma thachi Grego & Szekeres sp. nov. are described as new taxa, and the zoogeographical partitioning of the Southeast Asian clausiliid fauna is discussed in the light of the novel distribution data of these and some other noteworthy members of the family.

Key words. Garnieriinae, Phaedusinae, new taxa, Southeast Asia, zoogeography

New taxa. Grandinenia dautzenbergi abdoui Grego & Szekeres, 2019; Grandinenia muratovi Grego & Szekeres, 2019; Oospira duci smidai Grego & Szekeres, 2019; Phaedusa micropaviei hmongorum Grego & Szekeres, 2019; Synprosphyma phuonganhae Do & Szekeres, 2019; and Synprosphyma thachi Grego & Szekeres, sp. nov.

Date of publication. April 2019

 

Taxonomic reassessment of Megalobulimus toriii (Gastropoda, Strophocheilidae)

José H. Fontenelle, Barbara M. Tomotani & Rodrigo B. Salvador

Abstract. The taxonomical status of Megalobulimus toriii Morretes, 1937 from southeastern Brazil is reassessed herein. A large series of shells of M. toriii and M. yporanganus (Ihering & Pilsbry, 1901) were analysed for conchological features and measured for a principal component analysis. The material included recent shells and sub-fossil specimens (no living specimens or ethanol-preserved  specimens could be procured). Megalobulimus toriii falls within the spectrum of morphological variation of M. yporanganus and is thus considered its synonym. Megalobulimus yporanganus was originally described from the Ribeira Valley in São Paulo state and its present distribution includes only other localities in this valley. However, the species is also known from Holocene archaeological contexts (shell mounds) and karst outcrops, with the oldest records dating from circa 10,800–9,200 YBP. Its past distribution extended southwards to the coast of Santa Catarina state.

Key words. Brazil, Megalobulimus yporanganus, principal component analysis, sambaqui, shell mounds, Stylommatophora

Date of publication. April 2019

 

The works and new nominal molluscan taxa introduced by Malcolm Edmunds (1938–2017) with an obituary

Nathalie Yonow

Date of publication. April 2019