Diversity of terrestrial gastropods in Kabylia region (Tizi-Ouzou, Northern Algeria)

The goal of this study was to record the malacofauna of the Kabylia region, Tizi-Ouzou, in Northern Algeria, at the edge of the Mediterranean Sea, and to report the distribution pattern of terrestrial gastropod diversity in five different types of habitat (dune, agricultural fields, rural sites, forests, and mountain locations). A total of 33 species of terrestrial snails and slugs were recorded, which represented 27 genera of 19 families, mainly Geomitridae and Helicidae. The rural habitat was the richest, with 23 species, while the mountain habitat yielded 20 species. The dune and forest habitats showed the smallest species richness.

Diversity and abundance of terrestrial gastropods in Skikda region (North-East Algeria): correlation with soil physicochemical factors

Background The inventory process is the first method to protect and safeguard animal biodiversity. This study carries out a quantitative and qualitative inventory of terrestrial gastropods at three sites in Skikda province (north-eastern Algeria). The relationship between terrestrial gastropod diversity and soil physicochemical factors was investigated using statistical analyses. Results The inventory data reveals the presence of four families and eight species showing varied predominance rates of Cornu aspersum species according to each site in the city of Skikda (Azzaba 53.88%; Ben-Azzouz 56.12%; El-Hadaiek 37.92%). The maximal specific richness was registered in the El-Hadaiek site (seven species), and the highest mean richness was noted in the Ben-Azzouz site (392 individuals). Of the eight gastropod species identified, three species (Cornu aspersum, Cantareus apertus and Rumina decollate) were classified as constant species. The Shannon–Weaver diversity and equitability indices vary by site. Conclusion The presence of certain species in one site and their absence in other sites, as well as the variation in ecological indices, could be attributed to the effect of soil-physicochemical factors.

Diversity and abundance of terrestrial Gastropods on the slopes of Mount Arjuna-Welirang, East Java, Indonesia

Nurhayati PA, Affandi M, Nurinsiyah AS. 2021. Diversity and abundance of terrestrial Gastropods on the slopes of Mount Arjuna-Welirang, East Java, Indonesia. Biodiversitas 22: 4193-4202. Before this study, the latest list of land snail species from Mt. Arjuna-Welirang was published in 1952. The current study aims to update the list of terrestrial Gastropods in the area, focusing on Sumber Brantas Arboretum and Raden Soerjo Forest Park Conservation Area (Tahura), East Java, Indonesia. Live snails and dead shells were collected from 24 10 × 10 m2 sampling plots to determine species richness, composition, and abundance. Sampling was carried out by combining visual observation (direct collection) and sorting-sieving soil-leaf litter samples. Total 646 specimens belonging to eight families and 13 species were collected, all new records to the area. Thus, the number of species known from Mt. Arjuna-Welirang was increased to 16 species from nine families. The diversity index of the Mt. Arjuna-Welirang slope was 1.1, and the dominance index was 0.54. The Tahura had a higher diversity index than the Arboretum, at 2.0 and 0.38, respectively, but the dominance index for Tahura was lower (0.18 and 0.85, respectively). This was due to the dominance of Bradybaena similaris, an invasive species in the latter area. Less canopy cover and more human activity in the Arboretum are factors that might cause this discrepancy. Many land snail species are sensitive to desiccation and habitat disturbance. Therefore, minimizing habitat changes and human activities is necessary to maintain or increase native land snail species diversity.

Autochthonous Angiostrongylus cantonensis, Angiostrongylus vasorum and Aelurostrongylus abstrusus infections in native terrestrial gastropods from the Macaronesian Archipelago of Spain

The presence of zoonotic relevant Angiostrongylus cantonensis infections has recently been reported in rat final hosts and gastropod intermediate hosts in Tenerife, Spain. However, data on A. cantonensis, Angiostrongylus vasorum and Aelurostrongylus abstrusus prevalences in endemic gastropods for other islands of the Macaronesian Archipelago are still missing. In order to fill this gap, we conducted an epidemiological study on terrestrial native slug (Plutonia lamarckii) and snail (Cornu aspersum, Theba pisana, Rumina decollata) species in 27 selected locations of Tenerife, Gran Canaria, El Hierro, Lanzarote, La Palma and Fuerteventura. Overall, 131 terrestrial gastropods were collected in winter/spring season 2018/2019 and examined for the presence of metastrongyloid lungworm larvae via artificial digestion. The current data revealed a total prevalence of 4.6% for A. vasorum, 3.8% for A. abstrusus and 0.8% for A. cantonensis. In Tenerife, three lungworm species were detected, thereby re-confirming A. cantonensis endemicity for this island. Prevalences of snails (C. aspersum) originating from El Hierro were 5% for A. abstrusus and 15% for A. vasorum, respectively, with larval burdens up to 290 larvae per specimen. This epidemiological study indicates the presence of human, canine and feline lungworm species in Macaronesia, Spain. The current data—particularly those on anthropozoonotic A. cantonensis—call for a regular large-scale monitoring on intermediate hosts, paratenic hosts and definitive hosts to prevent further spread of lungworm-related diseases in humans and animals.

Composition and structure of Gastropoda in the Lavandula dentata L. (Labiatae) stations in the Ghazaouet region (Tlemcen, North-West Algeria)

An approach to the diversity of malacofauna associated with toothed lavender was carried out in three stations belonging to the coastal region of Ghazaouet (Wilaya de Tlemcen) from January to July 2013. The specific richness of gastropods is 14 species. Four species are accessories and ten others are accidental. The relative importance of snails varies by station and by month and season. Gastropods preferring certain humidity are easily collected in winter and spring. In April, the species richness is relatively important (6 species) in the 1st and 2nd stations respectively. Milax gagates has a frequency of 78.57% in the first station (Sidi-Aissa) and 57.14% in the 2nd station (Sidi - Amar). Helicella pyramidata has a frequency of 35.71% in station 3 (Bab Khroufa). Similarly, this Helicellinae has a density equal to 0.50 in the same station. Keywords: Lavandula dentata, terrestrial gastropods, diversity, bioecology, vertical distribution, Ghazaouet region (Tlemcen).

Terrestrial gastropods of Humaitá Forest Reserve, southwestern Brazilian Amazon

The molluscan fauna of southwestern Brazilian Amazonia is poorly known due to the lack of focused collection areas in the region since the early 20th century. The present study provides an inventory of the terrestrial gastropods from a forest fragment in the eastern Acre state, Brazil: the Humaitá Forest Reserve (“Reserva Florestal Humaitá”). Live specimens and empty shells were collected between August 2018 and January 2019. A total of 20 species were identified, distributed in 11 families. Most (13) of these species were recorded in Acre for the first time. Furthermore, we confirm the occurrence of Systrophia helicycloides (d’Orbigny, 1835) in Brazil, reiterate the synonymy of Plekocheilus pentadinus (d’Orbigny, 1835) with P. floccosus (Spix in Wagner, 1827), and synonymize Solaropsis peruviana Haas, 1951 with S. juruana Ihering, 1905.