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The aim of this work was to evaluate the spatial and temporal distribution of shrimp species in the Lake Nokoué-Cotonou Channel complex for an efficient management of the fishery. The results of one year sampling from five stations (North, South, East, Central and West) in the complex revealed the following proportions: Penaeus notialis 73.68%, Macrobrachium macrobrachion 13.81%, Macrobrachium vollenhovenii 5.36%, Penaeus monodon 2.68%, Macrobrachium felicinum 2.20%, Penaeus kerathurus 1.72%, Macrobrachium cf. zariquieyi 0.27%, and Macrobrachium equidens 0.27%. The species M. cf. zariquieyi and M. equidens were never reported from Benin, but are now found in Lake Nokoué. Spatially, Penaeus (Penaeus notialis) are more abundant in the west (Acadja concentration zone), while Macrobrachium (Macrobrachium macrobrachion) are more dominant in the east (near the Ouémé entrance) and north (near the Sô entrance) of the lake. Penaeus are strongly present in the lagoon complex from January to August, while Macrobrachium are more abundant in Lake Nokoué from September to December. Spearman's correlation analysis revealed that increasing salinity, pH, transparency and total dissolved solids (TDS) positively influenced the abundance of P. notialis , while increasing salinity, pH, transparency, and TDS negatively influenced the abundance of M. macrobrachion at the 5% significance level. For an efficient management of the shrimp fishery, it is desirable that the shrimp fishery in Lake Nokoué, mainly in the Cotonou Channel, which is a very sensitive area for their seasonal migrations, benefits from at least three months of respite per year, from November to January. This period corresponds to the strong migration of juvenile Penaeus towards the lake. This should allow many Penaeus to grow up and breed at least once in their lives, according to the species' life cycle presented. [ABSTRACT FROM AUTHOR]

Two new species of the genus Onycocaris are described, based on single specimens from Fiji and Moorea respectively. Onycocaris iti sp. nov. is closely related to the relatively widespread species, O. seychellensis Bruce, 1971; whilst O. brucei sp. nov. is a pseudo-cryptic species allied to O. quadratophthalma (Balss, 1921). [ABSTRACT FROM AUTHOR]

A new species of Palaemonella , P. sandyi sp. nov., is described on the basis of specimens collected in association with euphylliid scleractinian corals, Euphyllia glabrescens and E. cristata. Material was collected from the Maldives, Cebu in the Philippines, Semporna in Malaysia, and from Java, Bali, Sulawesi, Kalimantan, Ternate and Raja Ampat in Indonesia. The new species is similar to P. colemani and P. euphyllius , which are associated with euphylliid corals of the genus Fimbriaphyllia. The new species can be distinguished from P. colemani and P. euphyllius , as well as from the species P. philippinensis and P. smiti , which are both symbionts with plerogyrid scleractinians, on the basis of morphological characters in the rostrum and ambulatory pereiopods, colouration, and molecular data. [ABSTRACT FROM AUTHOR]

Here, the symbiotic palaemonid shrimp Hamodactylus boschmai is recorded from Korean waters for the first time, based on specimens collected from different invertebrate hosts by trimix diving at depths of between 45 and 60 m in Jejudo Island. This species can readily be distinguished from its congeners by the presence of a distinct supraorbital tooth, the proximal segment of the antennular peduncle having a single tooth on the distolateral margin, the presence of a denticulate lamina along the entire cutting edge of the fingers of the first pereiopod chela, and the chela of the second pereiopods having a strongly hooked tip on the movable finger. An illustrated description, colour photographs, and a comparison of partial mitochondrial cytochrome c oxidase subunit I gene sequences are provided. Résumé: La crevette Palaemonidae symbiotique Hamodactylus boschmai est signalée des eaux coréennes pour la première fois, à partir de spécimens collectés sur différents hôtes invertébrés en plongée trimix à des profondeurs de 45 à 60 m au large de l'île de Jejudo. Cette espèce peut être facilement distinguée de ses congénères par la présence d'une dent supraorbitale distincte, par le segment proximal du pédoncule antennulaire possédant une seule dent au bord disto-latéral, par la présence d'une lamelle denticulée tout au long du bord tranchant des doigts de la pince du premier péréiopode, la pince du second péréiopode présentant une extrémité fortement recourbée du doigt mobile. Une description illustrée, des photographies couleurs, et une comparaison des séquences partielles du gène de la sous-unité I de la cytochrome c oxydase mitochondriale sont fournies. [ABSTRACT FROM AUTHOR]

The palaemonid shrimp Macrobrachium macrobrachion is widely distributed in coastal rivers, estuaries and inland waters of West Africa. This species is economically important because it is the one of the two main freshwater shrimp commercially exploited by artisanal fisheries in southern Benin, besides showing great potential for aquaculture. Despite this, little is known about its reproductive biology in the natural environment. Considering these facts, the present study aimed to establish some breeding parameters for M. macrobrachion in Benin. Overall, 2424 specimens were collected between May 2015 and October 2016. Monthly changes in gonado-somatic index (GSI) and hepato-somatic index (HSI) suggest that the breeding season runs from July to October. In the Ouémé River Delta, the estimated size at first maturity is 8.16 cm TL in females, while it is 7.47 cm TL in males. In the Mono River/Grand-Popo Lagoon complex, the size at first maturity is 7.27 cm TL in females while it is 6.56 cm TL in males. The structure of the ovary as observed in females from either site just before spawning, shows the presence of two types of oocytes at different sizes and various developmental stages. Analysis of such ovarian structure suggests that M. macrobrachion has a synchronous oogenesis with a breeding season limited to a few months of the year. Fecundity was found to be between 3144 and 26 489 eggs in the Ouémé Delta, while it goes from 3124 to 22 660 eggs in the Mono River/Grand-Popo Lagoon complex. The present study provides important information on the reproductive biology of M. macrobrachion and of freshwater shrimp in general, and can also serve as a significant foundation for the aquaculture of species of freshwater shrimp. [ABSTRACT FROM AUTHOR]

Wnt4 (Wingless-type MMTV integration site family member 4) has been demonstrated to play critical roles in a wide variety of biological processes, including embryonic development, cell proliferation, and differentiation in vertebrates, but its function in crustaceans is still not clear. In the present study, the full-length wnt4 cDNA sequence was cloned and characterized for the ridgetail white prawn Exopalaemon carinicauda. The expression patterns of the wnt4 mRNA in embryos and larvae at different stages were investigated. The tissue distribution showed that wnt4 was obviously expressed in eyestalk and hepatopancreas. During embryonic development, the wnt4 was highly expressed in all developmental stages except the zygote, two-cell stage, and late zoaea stage. The wnt4 mRNA was expressed in Z1-Z5 and post-larval stages. Taken together, the present study indicates that the wnt4 gene may be involved in the regulation of embryonic and larval development in the ridgetail white prawn. [ABSTRACT FROM AUTHOR]

One species of Hippolytidae, Hippolyte californiensis Holmes, 1895, and one species of Palaemonidae, Periclimenes infraspinis (Rathbun, 1902), were collected in a single sample among sea grass in the northern Gulf of California, Mexico. Hippolyte californiensis is partly illustrated and compared to the descriptions available in the literature, noting minor differences with material from California where it was originally described. Diagnostic characters of P. infraspinis are also illustrated. Sex proportion and size distribution indicate a higher incidence of females (male : female ratio, 1 : 2.59), smaller size in males, a strong incidence of ovigerous females (31%), and a brood clutch of 82-200 embryos in P. infraspinis. In H. californiensis, males were more abundant (1.41 : 1), the incidence of ovigerous females was low (15%), and females carried 51-115 embryos. In both species, males, females, and ovigerous females were significantly different in size. These two species have not been reported as sympatric. [ABSTRACT FROM AUTHOR]

The p38 mitogen-activated protein kinases (MAPK) are a kind of Ser/Thr protein kinases that convert extracellular stimuli into a wide range of cellular response, appearing to function not only in stress stimuli but also in development. To explore the function of p38 MAPK in Palaemon carinicauda Holthuis, 1950, we cloned and characterized the full-length cDNA sequence (GenBank accession number KX893515) (designated as Pc-p38). The results showed that the open reading frame (ORF) of Pc-p38 was 1098 bp and it encoded a protein of 365 amino acids. Pc-p38 contained the conserved structures of a Thr-Gly-Tyr (TGY) motif and a substrate-binding site, Ala-Thr-Arg-Trp (ATRW), and was shown to have a close phylogenetic relationship to other p38 MAPKs in crustaceans. The tissue distribution patterns showed that Pc-p38 was widely expressed in all tissues, with highest expression in the hepatopancreas and ovary. Quantitative real-time PCR revealed that Pc-p38 was upregulated during ecdysis, reaching a peak at 5 min post-moult, suggesting that Pcp38 may be involved in muscle remodeling after moulting. In addition, the expression of Pc-p38 increased following exposure to different concentrations of mercury, in a dose- and time-dependent manner. In conclusion, an Pc-p38 gene was cloned and its role determined at different times postmoult and after stress from different concentrations of mercury, to further reveal the possible functions of p38 MAPK in P. carinicauda. [ABSTRACT FROM AUTHOR]

The first zoeal stage of the freshwater shrimp Macrobrachium surinamicum Holthuis, 1948 is described and illustrated based on hatchlings from an ovigerous female, collected in Rio Campupema, Abaetetuba, in the northern Brazilian state of Pará, and compared with the first zoeae of several other species of the genus occurring in Brazil. Although the first zoeae of the different species of Macrobrachium are morphologically very similar, they can still be separated by a combination of morphological characters but only M. surinamicum has one smooth seta on the maxillular endopod. Although a complete larval series of M. surinamicum presently remains unknown, as pereiopods 3-5 and pleopods are absent, the outcome of this study suggests that the larval development of this species is extended and includes at least seven larval stages. [ABSTRACT FROM AUTHOR]

A new sponge-associated species, Paraclimenaeus michaeli sp. nov. from Sulawesi, Indonesia, and Singapore, is described and illustrated. The new species can be distinguished from its congenerics by: (1) the downwards curved rostrum with 2 acute dorsal teeth subdistally, (2) the absence of subdistal teeth on the fixed finger of the major second chela, (3) the pairs of dorsal telson spines at about 0.33 and 0.66 of the telson length, (4) the caudal fan sparsely setose, and (5) the second pereiopods without subdistal teeth on fixed finger. To evaluate its relationship with congenerics and species of the related genera Apopontonia and Climeniperaeus, a phylogenetic analysis based on the 16S mitochondrial gene is presented. A key for the identification of the species in Apopontonia, Climeniperaeus and Paraclimenaeus is proposed. [ABSTRACT FROM AUTHOR]

We used both stomach content and stable isotope analyses to describe the feeding ecology of Siberian prawns Palaemon modestus (Heller, 1862), a non-native caridean shrimp that is a relatively recent invader of the lower Snake River. Based on identifiable prey in stomachs, the opossum shrimp Neomysis mercedis Holmes, 1896 comprised up to 34-55% (by weight) of diets of juvenile to adult P. modestus, which showed little seasonal variation. Other predominant items/taxa consumed included detritus, amphipods, dipteran larvae, and oligochaetes. Stable isotope analysis supported diet results and also suggested that much of the food consumed by P. modestus that was not identifiable came from benthic sources - predominantly invertebrates of lower trophic levels and detritus. Palaemon modestus consumption of N. mercedis may pose a competitive threat to juvenile salmon and resident fishes which also rely heavily on that prey. [ABSTRACT FROM AUTHOR]

In this study, the full-length cDNA sequence (GenBank accession number AGF80339.1) encoding a novel heat shock protein HSP70 family member (Heat shock cognate 70, EcHSC70) was cloned from the ridgetail white prawn, Exopalaemon carinicauda (Holthuis, 1950) [currently also as: Palaemon carinicauda Holthuis, 1950]. EcHSC70 full-length cDNA consists of 2452 bp, containing an open reading frame (ORF) of 1935 bp, and it encodes a 650-amino-acid protein with a theoretical size of about 71 kDa and a predicted isoelectric point of 5.32. Phylogenetic analysis showed that EcHSC70 can be categorized together with the known HSP70 family members reported in other crustaceans. Tissue-expression analysis revealed that EcHSC70 was constitutively expressed in all of the tested tissues, with a significantly increased expression in the gill post-moulting. Moreover, the relative rnRNA level of EcHSC70 tended to increase in the early stages of post-moulting (from 0 to 5 min), suggesting that EcHSC70 might take part in the recovery of E. carinicauda after moulting. In addition, under different levels of cadmium stress, EcHSC70 tended to be significantly expressed only after 24 h of cadmium exposure, and was more inducible by low concentrations of cadmium, as opposed to high concentrations. [ABSTRACT FROM AUTHOR]

The imidazole derivative KK-42 is frequently used as an insect growth regulator. However, the effect of KK-42 on prawn growth remains largely unknown. To explore the effect of KK-42 on the moult cycle of juvenile Macrobrachium nipponense (De Haan, 1849), 1.2-2.0 cm long prawns were collected from aquaculture grounds, and acclimated at 26 ± 1°C in running-water tanks for one week before the experiments. The prawns were soaked with KK-42 solution at a concentration of 1.95 x 10~4 mol/1 (treatment group) or without KK-42 solution (control group) for 1 min. Thereafter, a part of the prawns was used to measure body growth rate and moult cycle, and the rest, being at intermoult stage (C) and premoult stage (D), were used to quantitatively analyse the mRNA level of the cuticular chitinasel gene (Mnchi-1) and chitinase activity. The results showed that the average body weight of the treatment group was significantly higher than that of the controls. Meanwhile, the body growth rate increased more than 16% in the first two weeks after KK-42 treatment. The duration of the moulting period of the juvenile prawns was shortened by KK-42 treatment in the first two cycles among four consecutively-determined moult cycles, from 8.70 ± 1.07 and 9.81 ± 0.43 days to 6.93 ± 0.97 and 8.11 ± 1.20 days, respectively. The cuticular Mnchi-1 mRNA level as well as the chitinase activity at stage C showed an over 10- and 2-fold increase, respectively, after KK- 42 treatment. However, at stage D, only a modest rise was observed at 12 h (P <0.05). The results suggest that KK-42 can significantly up-regulate the cuticular Mnchi-1 gene expression and chitinase activity of the prawns at stage C, which may be one of the potential mechanisms of producing the KK-42-shortened moult cycle for juvenile M. nipponense. [ABSTRACT FROM AUTHOR]

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]

The river prawn Macrobrachium amazonicum Heller, 1862 occurs in limnic, brackish habitats in northeastern South America, with a broad distribution range, a wide phenotypic variability. Recently, representatives of populations from the Pantanal were reassigned to the newly described species M. pantanalense Dos Santos, Hayd & Anger, 2013, according to distinct morphology, lifehistory,, geographic distribution. Genetic distinctness is in a range that may be recognized as either inter- or intraspecilic, which raises the question to what extent genetic distance data alone should be used to determine whether two closely related populations belong to the same or different species. Here, we discuss the case of M. amazonicum, compare it with other cases of conflicting conclusions from studies on decapod crustaceans, mainly using morphological or genetic criteria. Based on these comparisons, we caution against a too simiplistic view of genetic distance as an exclusive criterion for the definition of “species” vs. “conspecific populations”. [ABSTRACT FROM AUTHOR]

This study aims to understand the reproductive and larval characteristics and the migratory patterns of the shrimp Macrobrachium yui (Holthuis, 1950). We conducted monthly samplings of the adult, juvenile and larval shrimp at fixed points in the Xuang River system in northern Laos. We determined the seasonal changes in size frequency distribution, difference in size among sampling sites, occurrence of drifting larvae, and physiological condition of the shrimp. The size distributions of M. yui differed significantly throughout the year among sections of the river system: small-sized juveniles occurred in the Xuang River, various size classes in the Pho Stream, and larger adults in the Bokengsakang cave stream. The gonadosomatic index of females is the highest in the Bokengsakang cave stream and the gonadosomatic index of males is the highest in the Pho Stream. Drifting larvae that had already completed morphological development for settlement on the substrate occurred only in the Bokengsakang cave stream, although the hatched larvae have a free-swimming larval period. The overall results indicate that M. yui females spawn in the Bokengsakang cave stream after mating with males during or before migration to the cave stream, and the hatched larvae remain in the cave stream until settling on the bottom. The life history migration of M. yui is attributed to the early stages of the life cycle, depending strongly on the cave stream. [ABSTRACT FROM AUTHOR]

The first stage of Pontonia simplex Holthuis, 1951 collected on the coast of Jalisco, Mexico, is described and compared with that of P. pinnophylax (Otto, 1821) and Ascidonia flavomaculata (Heller, 1864). [ABSTRACT FROM AUTHOR]

White spot syndrome virus (WSSV), an important shrimp pathogen that can affect both salt- and freshwater shrimp, has a high mortality rate that can reach up to 100% in 3-10 days. Therefore, we assessed the susceptibility of Macrobrachium nipponense (De Haan, 1849), a freshwater prawn native to Korea, to artificial WSSV infection. Although rearing in water containing WSSV-infected carcasses did not result in infection, M. nipponense was infected with WSSV after being fed a WSSV-containing diet, per os infection, or injection with the purified virus. In the feeding test, the first mortality was observed on the 7th day and cumulative mortality reached 30% by 3 weeks post-infection. After per os infection, experimental animals started dying on the second day and within 3 weeks mortality had reached 90%. In the injection test, the mortality was found to be dose-dependent. Prawn injected with 2.5 × 104, 900 and 80 copies/g body weight exhibited the first mortality at 1, 2 and 4 days post inoculation, with 100, 100 and 50% final mortality at 2, 10 and 12 days post inoculation, respectively. Histological observation revealed inclusion bodies in the gills, antennal glands and other tissues of ectodermal origin. Real-time polymerase chain reaction revealed the increase of viral titers, indicating viral replication in the inoculated host. This forms the first report of the experimental susceptibility of M. nipponense to WSSV. [ABSTRACT FROM AUTHOR]

The reproductive biology of Palaemon paucidens De Haan, 1844, from Goesan Lake, Korea, was investigated during the period May 2010-October 2011. The proportion of females was significantly greater than that of males (female?:?male ratio, 1?:?0.7). The gonadosomatic index (GSI) varied monthly, reaching a maximum in May and a minimum in September. Monthly variations in the proportions of ovigerous females showed peaks in April and May. The highest values of the GSI coincided with the breeding period of P. paucidens (April-August). There was no significant difference between the mean GSI of females with non-eyed and eyed eggs, indicating that P. paucidens is a non-consecutive breeder. There was a significant correlation between the number of eggs and the carapace length at early egg stages. There was no significant difference in the intercepts of the regressions of the number of eggs versus carapace length between females carrying non-eyed and eyed egg stages, indicating that there was no brood loss during the incubation period. Egg volume increased significantly (by 75.6%) as eggs developed from the non-eyed to the eyed stage. Reproductive output was 0.20 ± 0.04, based on dry weights in early egg stages. The results were compared with other studies of P. paucidens in Sukdang Lake and other species of palaemonids in different habitats. This comparison reveals intra- and inter-specific variations in reproductive traits of palaemonid shrimp. The phenomenon is suggested to be a result of adaptations to different environmental conditions. Variation in reproductive traits within the same species reflects a different life strategy adaptation in species that will require a different approach in fisheries management. Information on intra- and inter-specific variation in reproductive traits is important to be used as one basic issue of biological information to support an effective fisheries management of P. paucidens, which has been locally exploited in Korea and Japan. [ABSTRACT FROM AUTHOR]

The relationship between the depth of the carapace of shrimps of the genus Periclimenaeus and canal diameter of the sponges Ailochroia crassa, Aplysina fistularis, Callyspongia armigera, Ircinia fistularis, I. strobilina and Sidonops neptuni from Veracruz Coral Reef System National Park, SW Gulf of Mexico, Mexico, were studied. Thirty sponges were collected manually, using SCUBA, and placed underwater in hermetically sealed plastic bags, 1:1 formalin/alcohol solution was added to the plastic bags; then the crustaceans were manually removed and fixed in 70% ethanol. Correlations between mean depth of the carapace of a shrimp species and canal diameter of the sponges inhabited by that shrimp species were estimated. The total number of Periclimenaeus shrimps was 108, with three species associated with six species of sponges. The shrimps were found on seven reefs of the coral reef system. The most abundant species of shrimp were P. perlatus and P. wilsoni with 67 and 35 individuals, respectively. In the association of the shrimps with the sponges, P. perlatus was found in 84% of Aplysina fistularis specimens and P. wilsoni was found in 66% of Ircinia fistularis specimens. The deepest carapace was found in the females of P. pearsei with 3.96 ± 0.04 mm. The regression of the depth of the carapace of the shrimps against the canal diameter of the species of sponges showed a positive and significant relationship (P < 0.001). These correlations raise the need to explore the full range of morphological and physiological adaptations of species of the genus Periclimenaeus to the sponges they inhabit, and the geographical distribution of Periclimenaeus-sponge interactions is essential to understand how the use of sponge hosts has contributed to the biodiversity of shrimps throughout the SW Gulf of Mexico. [ABSTRACT FROM AUTHOR]

In the latter half of the 20th Century and the early part of the 21st the Asian shrimp species Palaemon macrodactylus began being reported from several world-wide locations. Literature records of Palaemon macrodactylus are herein collated, corroborated through examination of material where possible. Material from each main occupied region has been verified as P. macrodactylus, but records from Taiwan and Darwin do not refer to P macrodactylus. Some records still require verification in the absence of material examined. The data show that, in most cases, the first occurrence of P macrodactylus in a region is several years prior to the detection of the species. Biological, ecological and physiological aspects of the species are summarised to gain an understanding of why the species is such a successful invader. However, the factors favouring the introduction of P macrodactylus over other species of Pa/aemon remain unclear as many traits are shared with other species of the genus. Information on larval tolerances may provide further clues for the success of P macrodactylus. We hypothesis that the global distribution of the species has been achieved through a combination of at least three primary introductions from Asia and three secondary introductions, but the origin of the Argentinean population remains unclear. Small-scale secondary introductions have likely aided spread within a region. Regions at risk of invasion by P. macrodactylus include the Baltic Sea, southern Norway and South Africa, whilst further spread within occupied, broad regions should be expected. [ABSTRACT FROM AUTHOR]

New records are provided for four species of caridean shrimp (Alpheidae and Palaemonidae) from Sonora, Sinaloa, and Oaxaca, along the west coast of Mexico. Alpheus tenuis Kim & Abele, 1988 extends its northern range to Puerto Peñasco, Sonora. Alpheus martini Kim & Abele, 1988 is recorded for the first time outside of Panama (Alcatraz Island, Sonora). Pontonia simplex Holthuis, 1951 is recorded from Teacapan, Sinaloa, in the pen shell Atrina maura (Sowerby, 1835), which constitutes a new host record; additionally, its live colour pattern is described. The range of Pontonia margarita Smith, 1869 is extended along the Mexican coast south to Oaxaca. [ABSTRACT FROM AUTHOR]

In the Papaloapan River two freshwater prawns with abbreviated development have been recorded: Macrobrachium villalobosi (a stygobitic species) and Macrobrachium totonacum (an epigeal species). In this paper we describe four new species from this genus, and the distribution of these six species along the river basin. M. oaxacae nov. sp. occurs in the River La Junta, and together with M. cosolapaense nov. sp. is geographically close to the stygobitic species and M. totonacum, but differs from these in the following aspects: pigmentation, the number of rostral spines, and the relative proportions of the articles of the second pereiopod, of appendix masculina and appendix interna, and the number of spines on the appendix masculina. Macrobrachium mazatecum nov. sp. lives in two streams in Veracruz: the first close to Tierra Blanca Veracruz and the second on the Zapotal Veracruz near Mpio. Lerdo de Tejada. This species was also recorded in two springs near Valle Nacional Oaxaca, and differs from M. oaxacae nov. sp. and M. cosolapaense nov. sp. in the number of rostral spines, and the relative proportions on the articles of second pereiopod, of appendix masculina and appendix interna, and of the spines on the appendix masculina. Finally, Macrobrachium jacatepecense nov. sp. occurs only in a spring near Jacatepec, Oaxaca. This species differs from the other species in the relative proportions of the articles of the second pereiopod: however, it is very close to Macrobrachium oaxacae nov. sp. in the number of rostral spines, but based on the geographical distribution of both species and other features, it is clearly a different species. In this Papaloapan River basin, the distribution of this complex of species is very limited, because the various populations live in very restricted areas associated with springs or small streams, and without direct interconnections. All these new species are comparable with the epigeal Macrobrachium species in the southeast of Mexico that have abbreviated larval development. [ABSTRACT FROM AUTHOR]

During fieldwork in Raja Ampat, West Papua, Indonesia, in 2007, a pontoniine shrimp, most likely belonging to the genus Anchistus, was collected from a coral boring bivalve of the genus Spengleria. This is the first record of a pontoniine shrimp living in association with a boring bivalve. As it probably concerns a juvenile shrimp, its identity remains unclear. Its affinities with the Indo-West Pacific mollusc-associated genera and with congenerics are discussed. [ABSTRACT FROM AUTHOR]

Macrobrachium madhusoodani new species is described from the upper reaches of Ithikkara River, Kerala, South India. The species shares certain characters with M. scabriculum (Heller, 1862), M. aemulum (Nobili, 1906), and M. nobilii (Henderson & Matthai, 1910) in the number and arrangement of rostral teeth, while it differs remarkably from those three species in distinctive diagnostic characters: rostral formula 10-14/2-3 with 5-6 postorbital teeth; carapace smooth with distal end of rostrum straight; chelae with 4 denticles in the movable and 3 in the immovable finger, in the proximal part of the cutting edge; the distal part of the fingers of the second chelate legs are darkly pigmented except the tip. Three prominent pigment spots are found midlaterally on the last three abdominal somites, with prominent pigmentation at the tip of the telson. [ABSTRACT FROM AUTHOR]

This study estimates reproductive parameters (length at first maturity, reproduction period, and fecundity), mortality, and maximum sustainable yield for Macrobrachium amazonicum on Combu Island (Amazon estuary). Samples were taken monthly between March 2003 and February 2004. Ovigerous females were recorded throughout the year, with reproductive peaks in the middle of the flood period (March), in the low water period (September), and the peak dry period (December) of the Guamá River. The size at which 50% of the females were mature was 60.8 mm TL. Absolute fecundity varied between 40 and 3375 eggs per female. The exploitation rate for maximum sustainable yield (EMSY) for males was lower than that for females. For both sexes, EMSY was below the exploitation rates (E). The present study demonstrates the need for management of the prawn fishery on the islands in the Amazon estuary, such as establishing a minimum commercial size. [ABSTRACT FROM AUTHOR]

The article presents research on the unusual rostrum in Palaemon longirostris. It notes that the variation comprises variation in dorsal and central teeth, and the relative length and shape of the rostrum. Specimens are encountered with a rostral morphology well outside this background variation. It bears a single post-orbital tooth situated above the orbit. It shows that deformations in decapod crustaceans have been most attributed to parasitic infections. However, some studies indicates morphological abnormalities could be attributed to poor wound healing.

Importing exotic species always has the risk of these becoming introduced pests. In a study on ponds in the Golestan Province, Iran, a number of shrimps was caught and identified as Macrobrachium nipponense. Due to the morphological similarities between M. nipponense and M. rosenbergii, it may have been erroneously introduced instead of M. rosenbergii, or it may have come along with other released aquatic animals. Until now, the species had only been reported in Iran from the southern and south-eastern parts of the Caspian Sea. [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]

The article reports the first record and extension of the known distribution of the inland prawn, Macrobrachium Aracamuni Rodríguez, 1982 in Brazil, known also as decapoda, palaemonidae. This paper presents the record of the occurrence of the prawns on Brazilian territory and extending the known range of the species up to South America. Specifics used for the study are explained such as abbreviations, carapace length, and others. The species studied in this experiment were not previously recorded from Brazil. However, the series of specimens studied were collected from the upper Rio Negro drainage, State of Amazonas in Brazil.

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]

This study investigates the phenoloxidase activity of a glandular substance that is supposedly injected in prey by Speleonectes sp. Phenoloxidase in that substance may be derived from a hemocyanin-like component produced by glands of the injecting apparatus and may cause deleterious effects on prey. We describe general morphology of the postulated injection apparatus of Speleonectes sp. and measurements of phenoloxidase activity of the putative injected substance. We also describe deleterious effects of a manually injected phenoloxidase (laccase) on Palaemonetes pugio Holthuis, 1949. [ABSTRACT FROM AUTHOR]

The palaemonid genus Laomenes is re-established. The type species, Periclimenes (Corniger) ceratophthalmus Borradaile, associated with crinoids, differs from other Periclimenes Costa species at the generic level on the account of the epistome being armed with horns, the posterior rostral carina forming well developed supraorbital eaves, the presence of a supraocular tooth at the edge of the supraocular eaves, the eye with the cornea produced distally, and the mandible with a widened and multidentate incisor process. Three other crinoid associates, P. amboinensis (De Man), P. (Corniger) cornutus Borradaile, and Parapontonia nudirostris Bruce are now placed in the genus Laomenes. The monotypic genus, Parapontonia Bruce is considered to be a junior subjective synonym of Laomenes. A key and a checklist to the species of Laomenes known at present are provided. [ABSTRACT FROM AUTHOR]

The two caridean families, Gnathophyllidae Dana, 1852 and Hymenoceridae Ortmann, 1890, are reported for the first time from Taiwan with three species. One of these, Phyllognathea simplex Fujino, 1973, is herein recorded from the only male known for this species. The two other species, Gnathophyllum americanum Guérin-Méneville, 1855 and Hymenocera picta Dana, 1852, are widely known circumtropical species, but recently controversy arose if these two species are truly cosmopolitan or represent species complexes. The morphological characters and coloration of the Taiwanese material of these three species are described and illustrated. [ABSTRACT FROM AUTHOR]

The osmoregulatory response and oxygen consumption rate of the strictly freshwater prawn, Macrobrachium tuxtlaense were measured under different salinity conditions. The goal of these experiments was to explore how the adaptive process to the freshwater environment has proceeded from a metabolic point of view in a hololimnetic species. Nine to 11 intermoult prawns were exposed to salinities of 0, 5, 10, 15, 20, 25, and 30‰, respectively. Once oxygen consumption was measured, haemolymph osmolality was determined by sampling of 20 μl aliquots. The results indicate that the oxygen consumption rate decreased significantly with increasing salinity. The respiration of prawns exposed to 5‰ salinity was 56% higher than the rate of those exposed to 20 and 25‰. The prawns behaved as strong hyperregulators in low salinity; at higher salinities, the haemolymph osmolality showed a sharp increase, although it remained hyperosmotic to the medium; the isosmotic point was reached at 700 mOsm. Based on our results, M. tuxtlaense in general shows a pattern similar to that of other hololimnetic species, but with some unique aspects, such as a high isosmotic point and an inability to survive at salinities above 28‰. This suggests an advanced degree of adaptation to the freshwater environment. [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]

Macrobrachium lanchesteri is presumed to be one of the most common and widely distributed freshwater prawns inhabiting still or slow-moving waters in Myanmar. The reproductive biology of M. lanchesteri from the Zaw Gyi River and Taung Ta Man Lake in central Myanmar was studied based on the occurrence of ovigerous females and eggs in different developmental stages. The total numbers of specimens studied were 1307 from Zaw Gyi River and 757 from Taung Ta Man Lake. Ovigerous females were captured throughout the year. A higher percentage of ovigerous females was obtained from June to November. Carapace length of ovigerous females ranged from 6.3 to 12.5 mm and egg size (length) varied from 0.8 to 1.0 mm. Compared to other species, the eggs of M. lanchesteri are larger than those of M. olfersii (0.4-0.6 mm) and smaller than of M. lamarrei (1.1-1.5 mm). More than half of the eggs were still at an early stage of development for every month sampled. The incubation interval of the eggs was estimated to be less than one month, because of the presence or absence of eggs in the eyed stage during the period from February to March. [ABSTRACT FROM AUTHOR]

Three new species of Macrobrachium Bate, 1868, i.e., M. gurudeve, M. jayasreei, and M. kunjuramani, collected from the rivers Kabbini and Bhavani (east flowing rivers of Kerala State) are described here in detail. The most important diagnostic features of the species are: in M. gurudeve, the rostrum is broad with 7-9 upper (2 post-orbital) and 3-5 ventral teeth, characteristically arranged; telson broad, dorsal pairs of spines situated at the distal third, and inner distal pair of spines very short; 2nd cheliped with carpus shorter than chela, and fingers ¾ of palm; appendix masculina with 1 long and 4 short distal spinous setae and 13 and 4 stiff lateral setae in two rows; uropodal exopod without accessory spine. In M. jayasreei, the rostrum is very slender, with 7-8 (1 or 2 post-orbital) and 4-5 ventral teeth, maximum width of the rostrum at the level of 2nd ventral tooth, and distal ventral tooth widely separated from the remaining ones; telson slender with 2 pairs of dorsal spines at distal half, and inner distal pair very long and slender; 2nd pair of pereiopods with carpus longer than chela and fingers about half as long as palm, as well as palm longer than half carpus; appendix masculina with 6 distal, stiff spinous and 9 lateral stiff setae, uropodal exopod without accessory spines. In M. kunjuramani, rostrum broad with 7-9 (2 post-orbital) dorsal and 4-5 ventral teeth, characteristically arranged; cephalothorax shorter than rostrum; telson slender with dorsal spines situated at the distal half, and inner distal pair of spines slender; 2nd pereiopods with carpus longer than chela, fingers half as long as palm; appendix masculina with 3 distal, stiff spinous and 6 lateral stiff setae; uropodal exopod with accessory spine. The colouration of the three species is also described. [ABSTRACT FROM AUTHOR]