The African weakly electric fishes Pollimyrus isidori and Pollimyrus adspersus (Mormyridae) produce elaborate acoustic displays during social communication in addition to their electric organ discharges (EODs). In this paper, we provide new data on the EODs of these sound-producing mormyrids and on the mechanisms they use to generate species-typical sounds. Although it is known that the EODs ar...

Recordings from the muscles of the pyloric chamber of the shrimp Palaemon display a rhythmic pattern which is either monophasic or biphasic, and is different from the triphasic pyloric pattern of large decapods. Identification of the pyloric neurones in the stomatogastric ganglion and study of their synaptic relationships indicate that the pyloric circuit of Palaemon is very similar to the pylo...

In euryhaline crustaceans, sensitivity to toxic trace metals may be linked to osmoregulation and salinity conditions. This study investigated if grass shrimp (Palaemonetes pugio) populations from different salinity regimes differed in sensitivity to cadmium (Cd). Grass shrimp were collected in May 2011 from two marsh sites with average salinities of ~3.0 ppt and 24.0 ppt. Groups were acclimated...

The sunflower stem weevil, Cylindrocopturus adspersus (LeConte) (Coleoptera: Curculionidae), has caused yield losses across much of the western Great Plains. Little is known about the field biology of this pest. Simple prediction models, such as degree-day models, are an integral tool for development of C. adspersus management strategies. Using data collected in Colorado, Kansas, and Nebraska, ...

A new species of Morulina from China is described and illustrated. It is close to M. orientis Tanaka from Japan and M. himalayana Cassagnau from Nepal. There are 12 tubercles on the head of all three species, but they can be separated by a number of chaetotaxic characters. A key for identification of all the species in the genus is given.

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First stage larval marsh grass shrimp, Palaemonetes vulgaris, were exposed to patterns of diurnal, semidiurnal, and constant hypoxia to evaluate effects on growth and to determine if there was a consistent relationship between exposures. A comparison of growth with cyclic exposures versus constant low dissolved oxygen (D.O.) concentrations equivalent to the minima of the cycles showed the cycli...