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1.
Naturwissenschaften ; 102(5-6): 37, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26040240

RESUMO

Approximately 30% of the genera of Scrophulariaceae s.str. have a staminode, which is the remnant of a sterile stamen. However, there are no studies of the functionality or evolutionary pattern of staminodes in that family. This paper investigates three Scrophularia species with different staminode sizes to determine if the staminode safeguards nectar from dilution by rainwater and if it influences pollinator behavior. We also study staminode evolution and ancestral state reconstruction onto a phylogeny containing 71 species and subspecies with four different staminode developmental stages: tiny, large, enormous, and absent. The results showed that large staminodes did not hinder nectar collection or modify pollinator-visiting time but acted as a barrier to reduce rainwater entry. The latter reduced the dilution of nectar, which did not occur with tiny staminodes. The phylogenetic study revealed that the ancestral state in the genus corresponds with the presence of a large staminode vs. the tiny and enormous staminodes that are considered as derived. The complete disappearance of the staminode has occurred independently at least twice. Events occurred that increased or reduced the staminode size in one of the clades (Clade II), which includes species of sect. Caninae; most of these events occurred during the Pleistocene (0.6-2.7 Ma).


Assuntos
Filogenia , Scrophularia/anatomia & histologia , Scrophularia/classificação , Néctar de Plantas/fisiologia , Estruturas Vegetais/anatomia & histologia , Estruturas Vegetais/fisiologia , Polinização , Chuva
4.
Folia Biol (Krakow) ; 53(3-4): 197-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-19058543

RESUMO

In summer 2002, allis shad infected with Lernaea cyprinacea (L.) were detected in the Guadiana River, southwestern Spain. This is the first documented report ofL. cyprinacea parasitizing allis shad in its natural range.


Assuntos
Copépodes/fisiologia , Doenças dos Peixes/parasitologia , Peixes/parasitologia , Doenças Parasitárias em Animais/parasitologia , Animais
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