Fred Naggs

Carbon and oxygen isotope variations within the shell of an African land snail (Limicolaria kambeul chudeauiGermain): a high-resolution record of climate seasonality?:

Stable isotope analyses at high-resolution intervals along the growth axis of a shell of the land snail Limicolaria kambeul chudeaui Germain, collected in Ethiopia, show a cyclic pattern of d18O variation. The cycles have regular periodicity but vary in amplitude. The shape and amplitude of the shell d18O cycles is consistent with seasonal changes in the amount and isotopic composition of the rainfall, coupled with tempera ture and evaporative effects. The number of cycles (10) corresponds to the estimated lifespan of Limicolaria. Generally constant d13C values suggest unvarying diet, environmental CO2 influences, and metabolism throughout the snails life, except for one interval of large variations in both d13C and d18O that may be related to the onset of reproductive activity. If similar results can be obtained for fossil shells, they may provide a high-resolution record of past seasonal climate variability.

Karyotypes of operculate land snails of the genus Cyclophorus (Prosobranchia: Cyclophoridae) in Thailand

Summary Although earliest known records of the Cyclophoridae are from the European Mesozoic, Cyclophorus is a genus of dioecious terrestrial prosobranchs that currently ranges from South Asia to the Western Pacific region. Karyotypes of ten species of Cyclophorus have been examined from Thailand. Haploid and diploid chromosome numbers were invariant (n = 14, 2n = 28, FN = 56), but the karyotypes varied along a continuum with 14 metacentric chromosomes in C. volvulus while the remaining species contain unique representatives of every summed combination of metacentric and submetacentric types from 13m + 1sm to 6m + 8sm. The two larger species, C. aurantiacus and C. malayanus, exhibit the same karyotypes of 7m + 7sm. Karyotypes among populations of C. fulguratus showed variation between the central (12m + 2sm) and northeastern regions (13m + 1sm) of Thailand. Among the species with unique karyotypes, northern species possess a higher metacentric number relative to southern species. The ZZ-ZW sex-determining chromosomes were observed in C. fulguratus from Phuwiang, C. malayanus from Sramorakot and C. volvulus from Wang Kanlueang. Taxonomic and evolutionary implications of the present findings are discussed.

Restricted genetic variation in populations of Achatina (Lissachatina) fulica outside of East Africa and the Indian Ocean Islands points to the Indian Ocean Islands as the earliest known common source.

The Giant African Land Snail, Achatina ( = Lissachatina) fulica Bowdich, 1822, is a tropical crop pest species with a widespread distribution across East Africa, the Indian subcontinent, Southeast Asia, the Pacific, the Caribbean, and North and South America. Its current distribution is attributed primarily to the introduction of the snail to new areas by Man within the last 200 years. This study determined the extent of genetic diversity in global A. fulica populations using the mitochondrial 16S ribosomal RNA gene. A total of 560 individuals were evaluated from 39 global populations obtained from 26 territories. Results reveal 18 distinct A. fulica haplotypes; 14 are found in East Africa and the Indian Ocean islands, but only two haplotypes from the Indian Ocean islands emerged from this region, the C haplotype, now distributed across the tropics, and the D haplotype in Ecuador and Bolivia. Haplotype E from the Philippines, F from New Caledonia and Barbados, O from India and Q from Ecuador are variants of the emergent C haplotype. For the non-native populations, the lack of genetic variation points to founder effects due to the lack of multiple introductions from the native range. Our current data could only point with certainty to the Indian Ocean islands as the earliest known common source of A. fulica across the globe, which necessitates further sampling in East Africa to determine the source populations of the emergent haplotypes.

Phylogenetic relationships of the operculate land snail genus Cyclophorus Montfort, 1810 in Thailand.

Operculate land snails of the genus Cyclophorus are distributed widely in sub-tropical and tropical Asia. Shell morphology is traditionally used for species identification in Cyclophorus but their shells exhibit considerable variation both within and between populations; species limits have been extremely difficult to determine and are poorly understood. Many currently recognized species have discontinuous distributions over large ranges but geographical barriers and low mobility of snails are likely to have led to long periods of isolation resulting in cryptic speciation of allopatric populations. As a contribution towards solving these problems, we reconstructed the molecular phylogeny of 87 Cyclophorus specimens, representing 29 nominal species (of which one was represented by four subspecies), plus three related out-group species. Molecular phylogenetic analyses were used to investigate geographic limits and speciation scenarios. The analyses of COI, 16S rRNA and 28S rRNA gene fragments were performed using neighbour-joining (NJ), maximum likelihood (ML), and Bayesian inference (BI) methods. All the obtained phylogenetic trees were congruent with each other and in most cases confirmed the species level classification. However, at least three nominate species were polyphyletic. Both C. fulguratus and C. volvulus appear to be species complexes, suggesting that populations of these species from different geographical areas of Thailand are cryptic species. C. aurantiacus pernobilis is distinct and likely to be a different species from the other members of the C. aurantiacus species complex.

Pupilloidea of Pakistan (Gastropoda: Pulmonata): Truncatellininae, Vertigininae, Gastrocoptinae, Pupillinae (In Part)

Abstract. Based on over 3,500 dry shells and alcohol-preserved specimens from 77 localities, new records of 12 species (Truncatellina callicratis (Scacchi), T. himalayana (Benson), Boysia boysii (L. Pfeiffer), Vertigo antivertigo (Draparnaud), V. pseudosubstriata Ložek, Gastrocopta avanica (Benson), G. huttoniana (Benson), G. klunzingeri (Jickeli), Pupilla muscorum (Linnaeus), P. annandalei Pilsbry, P. turcmenica (O. Boettger), P. signata (Mousson)) are given; ten species (Columella nymphaepratensis sp. nov., Truncatellina ayubiana sp. nov., T. babusarica sp. nov., Vertigo superstriata sp. nov., V nangaparbatensis sp. nov., Boysidia tamtouriana sp. nov., Pupilla khunjerabica sp. nov., P. satparanica sp. nov., P. ziaratana sp. nov., P. paraturcmenica sp. nov.) are described. Shell variation is discussed for most species; the reproductive system is described and illustrated for nine species. Northern Pakistan, with its broader altitudinal range and generally wetter environmental conditions, has the highest diversity of pupilloids belonging to the genera discussed herein. Of the 22 species discussed in this report, ten species are currently considered endemic to Pakistan, the other 12 species being known from elsewhere in the region (Asia, Europe, and the Holarctic). The pupilloid fauna displays a high degree of Palaearctic/Holarctic influence at the generic level.

Systematics of the family Plectopylidae in Vietnam with additional information on Chinese taxa (Gastropoda, Pulmonata, Stylommatophora).

Abstract Vietnamese species from the family Plectopylidae are revised based on the type specimens of all known taxa, more than 600 historical non-type museum lots, and almost 200 newly-collected samples. Altogether more than 7000 specimens were investigated. The revision has revealed that species diversity of the Vietnamese Plectopylidae was previously overestimated. Overall, thirteen species names (anterides Gude, 1909, bavayi Gude, 1901, congesta Gude, 1898, fallax Gude, 1909, gouldingi Gude, 1909, hirsuta Möllendorff, 1901, jovia Mabille, 1887, moellendorffi Gude, 1901, persimilis Gude, 1901, pilsbryana Gude, 1901, soror Gude, 1908, tenuis Gude, 1901, verecunda Gude, 1909) were synonymised with other species. In addition to these, Gudeodiscus hemmeni sp. n. and Gudeodiscus messageri raheemi ssp. n. are described from north-western Vietnam. Sixteen species and two subspecies are recognized from Vietnam. The reproductive anatomy of eight taxa is described. Based on anatomical information, Halongella gen. n. is erected to include Plectopylis schlumbergeri and Plectopylis fruhstorferi. Additionally, the genus Gudeodiscus is subdivided into two subgenera (Gudeodiscus and Veludiscus subgen. n.) on the basis of the morphology of the reproductive anatomy and the radula. The Chinese Gudeodiscus phlyarius werneri Páll-Gergely, 2013 is moved to synonymy of Gudeodiscus phlyarius. A spermatophore was found in the organ situated next to the gametolytic sac in one specimen. This suggests that this organ in the Plectopylidae is a diverticulum. Statistically significant evidence is presented for the presence of calcareous hook-like granules inside the penis being associated with the absence of embryos in the uterus in four genera. This suggests that these probably play a role in mating periods before disappearing when embryos develop. Sicradiscus mansuyi is reported from China for the first time.

Novel shell device for gas exchange in an operculate land snail

The operculum of terrestrial snails tightly seals the shell aperture providing protection from predators and body-water loss. To allow respiration with a closed operculum, operculate land snails repeatedly evolved shell devices such as tubes or channels that open to the air. In all Asian members of the Alycaeidae, an externally closed tube lies along the suture behind the aperture that possesses a small internal opening into the last whorl at the tubes anterior end. However, this structure presents a paradox: how is gas exchanged through an externally closed tube? Here we show that many microtunnels open into the tube and run beneath radial ribs along the growth line of the last whorl in Alycaeus conformis. These tunnels open to the outside of the shell surface near the umbilicus. Examination under high magnification revealed that the outermost shell layer forms these tunnels only in the whorl range beneath the sutural tube. Each tunnel (ca 16 µm diameter) is far narrower than any known metazoan parasite. These findings support our hypothesis that the externally closed sutural tube functions with microtunnels as a specialized apparatus for predator-free gas exchange with minimal water loss when the operculum seals the aperture.

An annotated catalogue of type specimens of the land snail genus Cyclophorus Monfort, 1810 (Caenogastropoda, Cyclophoridae) in the Natural History Museum, London

Abstract The collection of land caenogastropod snails in the genus Cyclophorus Monfort, 1810 housed in the Natural History Museum, London (NHM), includes 52 type lots. Lectotypes have been designated for 43 available species-level names to stabilize existing nomenclature, two previously designated lectotype, two holotypes, one paratype, one syntype, one possible syntype and two paralectotypes are also listed. A complete catalogue of the Cyclophorus types in NHM, London is provided for the first time.

The Sri Lankan endemic semi-slug Ratnadvipia (Limacoidea: Ariophantidae) and a new species from southwestern Sri Lanka

Abstract The endemic Sri Lankan land‐snail genus Ratnadvipia is reviewed and a new species is described. Detailed descriptions of the shell, external morphology of the animal, reproductive anatomy, spermatophore and radula of Ratnadvipia irradians and the new species are provided. Distributional data collected to date for the two species are reviewed. Both species are associated with the highly fragmented rain forests of Sri Lankas wet southwestern quarter. R. irradians is the most wide‐ranging of Sri Lankas endemic land snails. It extends into the drier parts of the island and occurs in synanthropic habitats such as home gardens. The new species is largely restricted to the lowland rain forests of the southern part of the wet lowlands. Both species appear to be at least partly arboreal, but little is known of their ecology.

Annotated checklist of the terrestrial gastropods of Nepal.

Abstract This is the very first checklist of the terrestrial gastropods of Nepal. It includes 138 species and six subspecies, of which 22 species are endemic and four are introduced. It highlights 34 species recorded for the first time in Nepal and provides new distribution records for another 30 species.