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The bopyrid isopod Probopyrus pandalicola (Packard, 1879) is a large, noticeable, hematophagous ectoparasite of palaemonid shrimps, including the daggerblade grass shrimp Palaemonetes pugio Holthuis, 1949. Bopyrids affect grass shrimp physiology and may also affect predator-prey dynamics. The purpose of this study was to determine whether the isopod affected the behavior and/or camouflage of grass shrimp, thereby altering the predation preferences of the mummichog Fundulus heteroclitus (Linnaeus, 1766). To determine whether the isopod affected predator preference through behavioral and/or camouflage alterations, paired combinations of unparasitized, parasitized, and marked shrimp were presented to mummichogs. One branchiostegite of some of the unparasitized shrimp was marked with black paint to mimic the bopyrid parasite. Mummichog predation preference and shrimp behavior immediately prior to predation events were recorded. All shrimp behavior was classified as motionless, walking, swimming, or backward thrusting. Immediately prior to predation, parasitized shrimp swam more (p = 0.0477) and backward thrusted less (p = 0.0272) than unparasitized shrimp. Mummichogs exhibited a preference for the more active shrimp (80.7% of shrimp; p <0.0001), and also for the less camouflaged (parasitized or marked) shrimp (81.5% of shrimp; p = 0.0011) if there was no difference in shrimp behavior. Parasitized shrimp were preferentially consumed (51/85 shrimp) when paired with unparasitized shrimp (p = 0.0089), but not with marked shrimp (p = 0.0837). A 30-min activity budget was created for each type of shrimp both in the presence and absence of predators; neither the parasite nor marking affected their behavior over 30 min (p = 0.1005). The major finding of this study was that P. pandalicola affected the predation preferences of F. heteroclitus by altering the behavior and/or camouflage of the grass shrimp. Parasitization alters predator-prey dynamics by decreasing the camouflage and the frequency of backward-thrusting behavior by the host when it is threatened by predation, which thereby decreases the ability of shrimp to escape from predators. [ABSTRACT FROM AUTHOR]

A fourth species of the stygobiotic blind prawn genus, Typhlocaris Calman, 1909 is described as T. ayyaloni n. sp. and illustrated in detail. The description is based on 18 specimens collected in a brackish, sulfidic warm-water pool in the 'Ayyalon Cave', a recently discovered karstic complex in Israel. Morphological comparison with congeners and some preliminary data on the behaviour of the new species and on its hypogeic habitat are also brought in brief. As no egg-bearing females were observed in the cave throughout an entire year, it is assumed that the warm and sulfidic water pool is only a feeding ground and that the prawn reproduces in some as yet unknown underground cavities, with presumably more appropriate environmental conditions. [ABSTRACT FROM AUTHOR]

Morphogenesis and variations in biochemical composition of the eggs of the prawn, Macrobrachium nipponense were studied during embryonic development. Eight morphological stages were defined. These are: the fertilized egg, cleavage, blastula, gastrula, egg-nauplius, egg-metanauplius, protozoea, and zoea. The whole embryogenesis lasts about 25 days at a water temperature of 18-22°C. Proteins, lipids, and carbohydrates were the main components of the embryos. During early embryonic development, protein content generally increased while the contents of lipid and carbohydrate decreased. It is suggested that the proteins in the yolk were used mainly in structural growth, whereas the lipids and carbohydrates were mainly used as energy sources. Lipid content increased while protein content decreased in the protozoea stage, showing that lipid is an important structural substance and protein can be utilized as an energy source, especially in late embryonic stages. Variations in biochemical composition were closely related to events in morphogenesis during embryonic development. The embryonic developmental stages used in the present study may be applied to other embryonic developmental studies of Macrobrachium, and be applicable in other palaemonids as well. [ABSTRACT FROM AUTHOR]

The pontoniine shrimp, Periclimenes adularans Bruce, 2003, previously known only by its type specimens from Australia, is recorded on the basis of some recently collected specimens from the East China Sea coast of Kyushu and the Ryukyu Islands, Japan as well as from the southwestern coast of Taiwan. The species' coloration in life is reported for the first time. Although the host species of P. adularans has not previously been recorded, the present study shows that this shrimp is associated with sea anemones, viz., Cerianthus filiformis Carlgren, 1922 and Megalactis hemprichii Ehrenberg, 1834. Supplementary morphological information on P. adularans is also given. [ABSTRACT FROM AUTHOR]