Planorbarius metidjensis explained

Planorbarius metidjensis is a freshwater lung snail.^[1]

Experiments confirmed it to be a host of the Schistosoma parasites, while the Bulinus truncatus freshwater snail has been known much longer as a carrier of schistosomiasis.^[2]

Description

The snail measures 8 mm x 16 to 18 mm. The shell is light yellowish, while the periostracum is brown, reddish or greenish. The body is nearly black with a grey foot and tentacles.^[3]

Schistosomiasis transmission

While P. metidjensis has been successfully infected with Schistosoma haematobium in the laboratory, in Morocco, no free-living infected snails have been found during a survey.^[4] Likewise, in the laboratory, snail specimens from Portugal and Salamanca were found to be very susceptible to infections by Schistosoma bovis strains gathered from the Salamanca region, but the 1977 study urged a prevalence survey of free-living snails.

In some areas, there are S. haematobium/S. bovis hybrids. P. metidjensis is immune to experimental infection with hybrid parasites collected in Corsica that contain 23% genetical material from S. bovis.^[5]

Distribution and habitat

The snail occurs in southwestern Morocco^[2] as well as in Algarve (Portugal) and Salamanca (Spain).^[6]

In a 2007 study carried out in Morocco, the snail was found in larger altitudes, and not in man-made water bodies like canals and artificial lakes. It tolerated a wide range of electrical conductivities (120 to 3650 microsieverts/cm) and up to 1.1 grams of chlorides per liter. It was often found together with Ancylus fluviatilis river snails.^[2]

References

• Brown D.S. (1994). Freshwater snails of Africa and their medical importance, 2nd edition. London: Taylor and Francis, 607 p.

page(s): 217, fig. 101c

External links

• Forbes, E. (1838). On the land and freshwater mollusca of Algiers and Bougia. The Annals and Magazine of Natural History, 2 (10): 250-255, pl. 11-12
• Graells, M.P. (1846). Catalogo de los moluscos terrestres y de agua dulce observados en España, y descripción y notas de algunas especies nuevas o poco conocidas del mismo país. Viuda é Hijos de Don Antonia Calleja, Madrid, and Calleja, Ojea y Compañia, Lima. vii + 23 pp., 1 pl.
• Image of Planorbarius metidjensis

Notes and References

1. MolluscaBase eds. (2022). MolluscaBase. Planorbarius metidjensis (Forbes, 1838). Accessed through: World Register of Marine Species at: https://www.marinespecies.org/aphia.php?p=taxdetails&id=1062886 on 2022-06-16
2. Habitats of Bulinus truncatus and Planorbarius metidjensis, the intermediate hosts of urinary schistosomosis, under a semiarid or an arid clima . . Yacoubi . B . 2007-03-06 . 101 . 311–316 . 10.1007/s00436-007-0500-4.
3. Web site: Planorbarius metidjensis (Forbes, 1838) . 2022-06-14 . AnimalBase . Göttingen University, Germany.
4. Étude rétrospective sur Planorbarius metidjensis et son rôle comme hôte intermédiaire potentiel dans la transmission de Schistosoma haematobium dans la région du Souss-Massa (Maroc) . . Yacoubi . B . 2020-03-22 . 113:123–129 . 10.3166/bspe-2020-0111 . fr . A Retrospective Study on Planorbarius metidjensis and Its Role as a Potential Intermediate Host in the Transmission of Schistosoma haematobium in the Souss-Massa Region (Morocco). free .
5. Morphological and genomic characterisation of the Schistosoma hybrid infecting humans in Europe reveals admixture between Schistosoma haematobium and Schistosoma bovis . PLoS Neglected Tropical Diseases . Kincaid-Smith . Julien . 2021-12-03 . 12 . 15 . 10.1371/journal.pntd.0010062. free . 10261/258654 . free .
6. Susceptibility of Planorbarius metidjensis from Portugal and Spain to Schistosoma bovis from Salamanca, Spain. . . Silva . ML . 1977-01-01 . 1 . 16 . 251–254 . 904368.