Juvenile growth rate is an important life-history trait that affects the size at maturity, and may influence the development of sexual ornamentation. The sword of several species of the genus Xiphophorus (Teleostei: Poeciliidae) is an elaborate secondary sexual trait that confers an advantage in terms of sexual selection, counterbalanced by locomotive and predatory costs. This study assesses di...

This paper describes the morphology of Cucullanus pinnai pinnai parasitizing Pimelodus maculatus in the Guandu River, Brazil, based on differential interference contrast (DIC) microscopy and scanning electron microscopy (SEM), providing new morphological data about this species of parasite. Nematodes were collected between May and October 2012 from specimens of Pimelodus maculatus in the Guandu...

Diet specificity is likely to be the key predictor of a predator's vulnerability to changing habitat and prey conditions. Understanding the degree to which predatory coral reef fishes adjust or maintain prey choice, in response to declines in coral cover and changes in prey availability, is critical for predicting how they may respond to reef habitat degradation. Here, we use stable isotope ana...

A new myxoporean species is described from a freshwater fish in Brazil. Myxobolus absonus sp. n. was found infecting Pimelodus maculatus captured in the river Piracicaba, State of São Paulo, Brazil. Cysts were found free in the opercular cavity. The spores are large (length--15.7 +/- 1.5 microns, width--10.2 +/- 0.7 microns; mean +/- S.D.) and oval in shape, with the anterior end slightly point...

Sexual selection via female mate choice can result in the evolution of elaborate male traits that incur substantial costs for males. Despite increased interest in how female mating preferences contribute to the evolution of male traits, few studies have directly quantified the locomotor costs of such traits. A sexually selected trait that could affect movement costs is the sword exhibited by ma...

The millipede genus Aponedyopus is endemic to Taiwan and contains three species. All previously described nominal species are considered to represent one species: Aponedyopus montanus Verhoeff, 1939 (the type species), including Aponedyopus reesi (Wang, 1957) and Aponedyopus maculatus Takakuwa, 1942, syn. n. Two further species are described as new: Aponedyopus similissp. n. and Aponedyopus lat...

abstract the cowpea weevil, callosobruchus maculatus is the one of the most destructive pests of the dried seeds including cowpea, chickpea, lentil, mung bean and broad bean. in the last few decades, the use of environmental friendly insecticides, particularly plant-based compounds, has attracted attention of many researchers. the objective of the present work was to evaluate the fumigant toxic...

The intensive use of synthetic pesticides in cowpea storage has led to the development of resistance by Callosobruchus maculatus and subsequent degradation of grain quality. In an attempt to circumvent these constraints, the susceptibility of C. maculatus to 2,2-dichlorovinyldimethyl phosphate (DDVP) and Lippia adoensis essential oil (EO) was investigated and variations in the proportions of nu...

Pimelodus (Pimelodidae) is a genus comprising a group of South American species with complex taxonomic relationships. Cytogenetics, polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP), and sequencing data of mitochondrial genes were analyzed to characterize 4 Pimelodus species: P. fur, P. heraldoi, P. maculatus, and Pimelodus sp. All populations presented 2n=56 chromos...

Ailinella gen. n. (Pseudophyllidea: Triaenophoridae) is proposed to accommodate Ailinella mirabilis sp. n. from Galaxias maculatus (Jenyns, 1842), a freshwater fish inhabiting the Andean lakes in Argentinean Patagonia. Ailinella belongs to the Triaenophoridae because it has a marginal genital pore, a follicular vitelline gland, and a ventral uterine pore. The new genus can be distinguished from...