Margarya melanioides explained

Margarya melanioides is a species of large operculate freshwater snail, an aquatic gastropod mollusc in the family Viviparidae, the river snails.

Margarya melanioides is the type species of the genus Margarya.[1]

Distribution

The distribution of Margarya melanioides includes Dian Lake, Erhai Lake, Jianhu Lake, Xihu Lake, and Cibi Lake in Yunnan Province, China. Former records in Daduitai Lake and Xingyun Lake are considered as a result of the mix-up of species name.

An average population density was 36 individuals per square meter in Dianchi Lake in 1940s, 0.7 individuals per square meter in 1990s and 0.068 individuals per square meter in Dianchi Lake in 2012.

According to the population ecology research by Song et al. (2013), the population of will collapse in the Dian Lake in 2015.

Description

The width of the shell is up to 64.3 mm. The height of the shell is up to 94.7 mm.

Shu et al. (2010) provided details about the shell and about the radula.[2]

The diploid chromosome number of Margarya melanioides is 2n=18.[2] [3]

Ecology

Margarya melanioides is a dioecious species. Females are ovoviviparous and one female lay 5-6 eggs per year. The newborn shell is about 8 mm in height. The snail will reach maturity in one year in a shell height about 30 mm.

The lifespan is 3–4 years.[4]

Human use

This species is extensively harvested as a human food source, but harvesting is one of its threats.[4]

External links

Notes and References

  1. Du . L. . Yang . J. . von Rintelen . T. . Chen . X. . Aldridge . D. . 2013 . Molecular phylogenetic evidence that the Chinese viviparid genus Margarya (Gastropoda: Viviparidae) is polyphyletic . . 58 . 18. 2154–2162 . 10.1007/s11434-012-5632-y . free .
  2. Shu . F. . Köhler . F. . Wang . H. . 2010 . On the shell and radular morphology of two endangered species of the genus Margarya Nevill, 1877 (Gastropoda: Viviparidae) from lakes of the Yunnan Plateau, Southwest China . Molluscan Research . 30 . 1. 17–24 .
  3. Chen Y. X., Zhang N. G., Zhang W. & Li J. K. (1996). "The karyotype study of Margarya yaungtsunghaiensis and M. melanioides (Viviparidae)". Zoological Research 17: 94-96. (In Chinese with English abstract)
  4. Song . Zhuoyan . Zhang . Junqian . Jiang . Xiaoming . Wang . Chouming . Xie . Zhicai . 2013 . Population structure of an endemic gastropod in Chinese plateau lakes: evidence for population decline . . 32 . 2. 450–461 . 10.1899/12-099.1 .