A cytogenetic study was carried out on the chromosomes and the nuclear DNA content of the freshwater goby Economidichthys pygmaeus (Pisces, Gobiidae). The species is characterized by a 2n=46 karyotype consisting of 12 submetacentric and 11 subtelocentric chromosome pairs (NF=70). Major (45S) rDNA genes are terminal-centromeric located on the short arm of a single medium-small sized submetacentr...

Multiple predator effects (MPEs) can modify the strength of pest regulation, causing positive or negative deviations from those that are predicted from independent effects of isolated predators. Despite increasing evidence that omnivory can shape predator-prey interactions, few studies have examined the impact of alternative plant food on interactions between multiple predators. In the present ...

Trypanosoma spp. of ground squirrels and most other rodents belong to the 3ubgenus Herpetosoma and have been recorded from approximately 80 to 90 different species of rodents throughout the world (Davis, 1952). They are often designated as leurisi-like after the type species, Trypanosoma (Herpetosoma) lewisi (Kent) Laveran & Mesnil. All are very similar in appearance and cannot be differentiate...

Females increase their risk of mating with heterospecifics when they prefer the traits of conspecifics that overlap with traits found in heterospecifics. Xiphophorus pygmaeus females have a strong preference for larger males, which could lead to females preferring to mate with heterospecific males; almost all sympatric X. cortezi males are larger than X. pygmaeus males. In this study, we show t...

Age, growth and maturation of the temperate ‘mini-maximalist’ Idiosepius notoides from Tasmania is described and compared with those of its tropical congener Idiosepius pygmaeus. Using statolith increment analysis, growth of I. notoides was best described by a power curve with a maximum age of 115 days recorded. Males have a shorter lifespan than females, however growth rates were similar betwe...