Morphological diversity and discrimination tools of the nonmarine ostracod Cypridopsis silvestrii across temporal and spatial scales from Patagonia

RAMOS, LORENA; PEREZ, ALEJANDRA PATRICIA; COVIAGA, CORINA; SCHWALD, ANTJE; ARISTEGUI, DANIEL; ALPERIN, MARTA; CUSMINSKY GABRIELA

ANAIS DA ACADEMIA BRASILEIRA DE CIENCIAS.

ACAD BRASILEIRA DE CIENCIAS

Lugar: Rio de Janeiro; Año: 2021

0001-3765

Geometric morphometric methods are powerful tools to discriminate between24 closely related ostracods taxa as well as to study the relationship between their25 morphological variations, taxonomy and paleoecology. Here, we apply valve outline26 analysis to identify the non-marine ostracod Cypridopsis silvestrii and compare it with27 Riocypris whatleyi juveniles and Eucypris cecryphalium. We further investigate C. silvestrii28 morphological variability throughout Argentinean Patagonia across different temporal and29 spatial scales. Morphological analyses allow the discrimination between C. silvestrii and R.30 whatleyi juveniles, pointing out differences in the posterior valve area and surface31 ornamentation. Cypridopsis silvestrii exhibits an extensive morphological variability but32 the three determined morphotypes inhabit a broad range of environments and could not be33 clearly linked to a particular environmental factor. Nevertheless, the "subtruncated"34 morphotype, which includes specimens previously described as E. cecryphalium, was35 found in five lakes from Southern Patagonia associated with low water conductivity as well36 as dominant cold and windy climatic conditions. Morphological differences between37 reproduction modes were also observed. These new results enhance the potential of38 ostracods as proxies for environmental and climate reconstructions, increase our39 understanding of morphological variations and set the ground for further taxonomic and/or40 molecular studies.