Brachyura

A total of 6 lung fluke species have been documented in Thailand, of which P. heterotremus is the most important, since it affects humans. Although P. westermani is found as metacercariae in the same crab species as P. heterotremus in Thailand, human infections with P. westermani have not been confirmed. To accurately discriminate between the individual metacercariae of these two species, we established a multiplex PCR method. Using this method, two products each were amplified from the metacercarial DNA samples of P. heterotremus (ca. 310 and 520 bp) and P. westermani (ca. 140 and 520 bp). In contrast, 520-bp products alone were found to be generated from the DNA samples of P. siamensis, P. bangkokensis and P. harinasutai, 3 other species of lung flukes known to occur in Thailand. Digestion of these 520-bp products with the restriction enzyme ScrFI could unequivocally discriminate species by the number and size of the produced band(s): 3 bands (ca. 60, 210 and 250 bp) for P. harina...

The native distribution of the blue crab Callinectes sapidus in the western Atlantic extends from Nova Scotia to Argentina. Introduced to Europe at the beginning of the 20th century, it is currently recorded almost ubiquitously in the Mediterranean and in the Black Sea. An overview of the occurrence, abundance, and ecological impact of the species in southern European waters is provided; additionally, we present a pragmatic assessment of its management scenarios, explicitly considering the dual nature of C. sapidus as both an invasive species and a fishery resource. We emphasise that the ongoing expansion of C. sapidus in the region may represent a stimulating challenge for the identification and implementation of future strategies in the management of invasive crustaceans. The impact of the invader could be converted into an enhancement of the services delivered by southern European coastal ecosystems, while mitigation costs could be transformed into profits for local populations.

The superfamily Portunoidea including extinct lineages is herein evaluated via cladistic analysis of adult morphological characters and traditional systematics. Nearly every fossil species has been examined via type material, or if this was not possible, through illustrations and original descriptions. The analyses indicate that the superfamily is much more diverse at the family level than has previously been recognized, and three subfamilies, Catoptrinae, Carcininae, and Macropipinae, are herein elevated to family status. One new family, Longusorbiidae; two new genera, Euronectes and Viaophthalmus; and two nomen nova are named herein in addition to the recognition of seven new combinations. The fossil record of each of the resulting families is evaluated and summarized, indicating that the superfamily extends into the Cretaceous but that many of the families are indeed much younger lineages.

Crabs has been known inhabiting diverse habitat. Crabs were found in the sea, and some other species were found in terrestrial or freshwater. Crabs is one of the important biotic components of the aquatic ecosystem as detrivore. Opak River is one of the major rivers in the Daerah Istimewa Yogyakarta (DIY), which has a various conditions and direct impact on biodiversity including the diversity of crabs. Up to now, there is no database of crab species from Yogyakarta. The aim of this research was to determine the diversity of crabs from Opak River. Research were carried out for 5 months between June and October 2013. Samples were characterized and identified morphologically. The results show that there are five species of crabs in Opak River. Parathelphusa convexa (De Man, 1879) was commonly found from upstream to downstream. Varuna litterata (Fabricius, 1798) was found in downstream to estuary (brackish water). The other three species were only found in the estuary area viz. Ocypode ceratophthalma (Pallas, 1772), Episesarma versicolor (Tweedie, 1940), and Scylla serrata (Forsskål, 1775). It can be concluded that diversity of crabs in the Opak River estuary area is higher than the upstream and downstream areas.

Juvenile blue crabs, Callinectes sapidus, extensively utilize oligohaline and freshwater regions of the estuary. With a presumptively larger surface-area-to-body weight ratio, juvenile crabs could experience osmo- and ionoregulatory costs well in excess of that of adults. To test this hypothesis, crabs ranging over three orders of magnitude in body weight were acclimated to either sea water (1,000 mOsm) or dilute sea water (150 mOsm), and gill surface area, water and sodium permeabilities (calculated from the passive efflux of 3H2O and 22Na+), gill Na+,K+-ATPase activity and expression were measured. Juveniles had a relatively larger gill surface area; weight-specific gill surface area decreased with body weight. Weight-specific water and sodium fluxes also decreased with weight, but not to the same extent as gill surface area; thus juveniles were able to decrease gill permeability slightly more than adults upon acclimation to dilute media. Crabs <5 g in body weight had markedly higher activities of gill Na+,K+-ATPase than crabs >5 g in both posterior and anterior gills. Acclimation to dilute medium induced increased expression of Na+,K+-ATPase and enzyme activity, but the increase was not as great in juveniles as in larger crabs.The increased weight-specific surface area for water gain and salt loss for small crabs in dilute media presents a challenge that is incompletely compensated by reduced permeability and increased affinity of gill Na+,K+-ATPase for Na+. Juveniles maintain osmotic and ionic homeostasis by the expression and utilization of extremely high levels of gill Na+,K+-ATPase, in posterior, as well as in anterior, gills. J. Exp. Zool. 305A:233–245, 2006.© 2006 Wiley-Liss, Inc.

Abstract: The stomatogastic nervous system of the crab, Cancer borealis, produces a slow gastric mill rhythm and a fast pyloric rhythm. When the gastric mill rhythm is not active, stimulation of the modulatory commissural ganglion neuron 1 (MCN1) activates a gastric mill rhythm in which the lateral gastric (LG) neuron fires in antiphase with interneuron 1 (Int1). We present theoretical and experimental data that indicate that the period of the MCN1 activated gastric mill rhythm depends on the strength and time course of the MCN1 evoked slow excitatory synaptic potential (EPSP) in the LG neuron, and on the strength of inhibition of Int 1 by the pacemaker of the pyloric network. This work demonstrates a new mechansim by which a slow network oscillator can be controlled by a much faster oscillatory neuron or network and suggests that modulation of the slow oscillator can occur by direct actions on the neurons and synapses of the slow oscillator, or indirectly by actions on the fast oscillator and its synaptic connection with the slow oscillator.

A new species of pinnotherid crab of the genus Afropinnotheres Manning, 1993, is described from the brown mussel, Perna
perna (Linnaeus, 1758), in southwestern India. This is the first record of the genus from the western Indian Ocean, the
other four species been recorded from the eastern Atlantic. The new species can be distinguished from all congeners in
possessing a more rounded male carapace, form of the chela, relatively longer ambulatory legs which have no natatory
setae, presence of dense pubescence on the male ambulatory legs, and the shape of the male and female telsons. The Indian
Pinnotheridae is also reviewed and the taxonomy of the species reappraised. The taxonomy of Pinnaxodes Heller, 1865,
and Holothuriophilus Nauck, 1880, is also discussed, in the context of their similarity to Afropinnotheres.

A modification to Performance-Tested MethodSM (PTM) 070601, Reveal® Listeria Test (Reveal), is described. The modified method uses a new media formulation, LESS enrichment broth, in single-step enrichment protocols for both foods and environmental sponge and swab samples. Food samples are enriched for 2730 h at 30C and environmental samples for 2448 h at 30C. Implementation of these abbreviated enrichment procedures allows test results to be obtained on a next-day basis. In testing of 14 food types in internal comparative studies with inoculated samples, there was a statistically significant difference in performance between the Reveal and reference culture U.S. Food and Drug Administration&#39;s Bacteriological Analytical Manual (FDA/BAM) or U.S. Department of Agriculture-Food Safety and Inspection Service (USDA-FSIS) methods for only a single food in one trial (pasteurized crab meat) at the 27 h enrichment time point, with more positive results obtained with the FDA/BAM reference ...

The activities of individual force-sensitive mechanoreceptors of the dactyl (terminal leg segment) of the crab, Carcinus maenas, have been recorded during free walking. These receptors have also been mechanically and electrically stimulated in freely moving animals to directly evaluate their function in locomotion. All force-sensitive mechanoreceptors fired during the stance phase of walking and were silent during swing. Receptor discharges showed regular phase relationships to bursts in motor neurons of leg muscles. Crabs walk laterally and use the legs of one side either in trailing to actively push the animal to the opposite side, or in leading, to less forcefully pull the animal in that direction. Individual force-sensitive mechanoreceptors differed in their patterns of activity during trailing or leading according to their location on the dactyl. Units of proximal receptors fired more vigorously when used in trailing than in leading. Discharges in trailing were also increased b...