Genetic, morphological, and life history traits variation in freshwater snails from extremely high environments of the Andean Altiplano

Abstract

Background: The isolated watersheds of the southwestern Andean Altiplano constitute a natural laboratory to study the evolutionary divergence of freshwater biota. Field observations showed that Biomphalaria snails from Parinacota, Colpa, and Caquena have different shell sizes. We performed morphometric analysis and common garden experiment to evaluate whether the observed shell variation has a genetic base and if this variation is manifested in other morphological characters and life history traits. Results: Network analysis revealed that the snails of Parinacota form a lineage genetically distinct from Caquena and Colpa. The morphometric analysis of the shell showed that the Parinacota snails were larger than Caquena and Colpa, both in nature and laboratory conditions, but there was no evidence of difference in the shape of the shell when compared using multivariate analyses. The number of eggs per ovicapsule was the only life history trait that was significantly different between lineages, although this difference may be also attributed to size of the progenitor; the oviposition rate did not differ between lineages or localities, and the hatching size and growth rate differed only at the locality level, not lineages. Conclusion:The results suggest that shell size of the snails has a genetic basis associated to the phenotype, while the expression and evolution of life history traits in extreme high environments are highly influenced by proximal causes.

Benthic macroinvertebrates community structure and physicalchemical characteristics at Lauca River Basin high altitude wetlands, Altiplano, Chile

“…It is one of the western-most fluvial-lacustrine basins of Miocene-Pliocene origin in Chile (Feitl et al, 2019, Rundel & Palma, 2000, and is filled by clastic and volcaniclastic sediments of lacustrine and alluvial origin (Kött et al, 1995). The aquatic ecosystems of this basin have been the subject of various studies anent ecology, morphology, morphometry, karyotypes, phylogenetics and phylogeography, finding high endemism of the species that inhabit them (Cárcamo-Tejer et al, 2021, Collado et al, 2011, Collado et al, 2014, Guerrero et al, 2015, Guerrero et al, 2017, Scott, 2010, Vila et al, 2010, Vila et al, 2013.…”