Phenotypic pattern over centric fusion clinal variation in the water-hyacinth grasshopper, Cornops aquaticum (Orthoptera: Acrididae)

The water-hyacinth grasshopper, Cornops aquaticum, occurs in freshwater environments in the New World between latitudes 23°N and 35°S. At the southernmost margin of this distribution the populations are polymorphic for three centric fusions (Robertsonian translocations). The frequencies of these chr...

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Detalhes bibliográficos
Autores: Colombo, Pablo Cesar, Remis, Maria Isabel
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2018
País:Argentina
Recursos:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/96648
Acesso em linha:http://hdl.handle.net/11336/96648
Access Level:acceso abierto
Palavra-chave:ACRIDIDAE
CENTRIC FUSIONS
CHROMOSOMAL CLINES
CORNOPS AQUATICUM
GRASSHOPPERS
MORPHOMETRIC EFFECTS
ORTHOPTERA
https://purl.org/becyt/ford/1.6
https://purl.org/becyt/ford/1
Descrição
Resumo:The water-hyacinth grasshopper, Cornops aquaticum, occurs in freshwater environments in the New World between latitudes 23°N and 35°S. At the southernmost margin of this distribution the populations are polymorphic for three centric fusions (Robertsonian translocations). The frequencies of these chromosome rearrangements increase southwards and the recombination in structural homozygotes and heterozygotes diminishes both along the middle and lower courses of the Paraná River. In the present paper we report a similar cline along the southward flowing Uruguay River. In addition, we report the morphological effects of two of these centric fusion polymorphisms, namely the fusions between chromosomes 2 and 5 of the standard complement (fusion 2/5) and chromosomes 3 and 4 (fusion 3/4) and extend this study to the Uruguay River. There is a strong inverse correlation of fusion frequency with temperature, which indicates that these polymorphisms may be related to increased tolerance of colder climates in this originally tropical species, or some other correlated variable. This study is a further example of chromosomal clines correlated with latitude and is one of a few examples of chromosome polymorphisms associated with phenotypic effects. Finally, it indicates ways of using this species for controlling pests.