In a replicated field experiment we studied the effects of natural densities of two exotic consumers, the predatory and herbivorous signal crayfish (Pacifastacus leniusculus) and the predatory rainbow trout (Oncorhynchus mykiss), on multiple trophic levels of a pond community. The goals were to: (1) determine the individual and combined effects of predators on macroinvertebrates, macrophytes, a...

Here we describe a new octoploid species of clawed frog from the Itombwe Massif of South Kivu Province, Democratic Republic of the Congo. This new species is the sister taxon of Xenopus wittei, but is substantially diverged in morphology, male vocalization, and mitochondrial and autosomal DNA. Analysis of mitochondrial “DNA barcodes” in polyploid clawed frogs demonstrates that they are variable...

The neural systems that control escape behavior have been studied intensively in several animals, including mollusks, fish and crayfish. Surprisingly little is known, however, about the activation and the utilization of escape circuits during prey-predator interactions. To complement the physiological and anatomical studies with a necessary behavioral equivalent, we investigated encounters betw...

The anti-predator behaviours of a New Zealand freshwater crayfish (Paranephrops zealandicus) to the native long-finned eel (Anguilla dieffenbachii) and the introduced brown trout (Salmo trutta) were investigated. Crayfish modified their behaviour in the presence of both trout and eels. However, a significantly greater number of defensive chela displays and swimming responses were made to eels t...

(Orconectes virilis) Mae Kindler and Jenna McCullough University of Minnesota – Itasca Biological Station Animal Behavior – June 29, 2010 Abstract Territoriality in female northern crayfish, Orconectes virilis, was studied through the observation of resident-intruder crayfish pair interactions based on size asymmetry. Resident-intruder pairings were chosen among 18 crayfish, with a total of 51 ...

Golgi impregnations reveal a variety of dendritic morphologies amongst Kenyon cells in the mushroom bodies of Drosophila melanogaster. Different morphological types of Kenyon cells contribute axon-like processes to five divisions of the medial and vertical lobes. Four of these divisions have characteristic affinities to antibodies raised against aspartate, glutamate, and taurine. A newly descri...

In January 2016, a 20-year-old female oriental small-clawed otter (Aonyx cinereus) from Night Safari in Singapore was euthanized and diagnosed with a thyroid gland carcinoma. Postmortem examination and histology also revealed metastasis to the regional lymph nodes and severe visceral pentastomiasis. Grossly, the lymph nodes were infested, and encapsulation was observed on the visceral serosal s...