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Two annual immigration cycles (1969-1970 cycle I; and 1981-1982 cycle II) of postlarvae (Pls.) of the white shrimp Litopenaeus vannamei (Boone, 1931) recorded at the same recruiting inlet and employing comparable sampling procedures, were analysed to examine interannual variability. The annual and monthly density values of both cycles were tested to infer a predictable immigration model that can be applied to assess the abundance and availability of shrimp Pls. at recruiting sites. A sustainable Pls. extraction programme must rely on a sound knowledge of the variability patterns of these parameters. Significant differences were noted in the annual density of Pls. between cycles. In cycle I, the annual mean density of postlarvae (μ d-3/yr-1/Pls.) was 3.1, while in cycle II it was 1.3. Successful reproduction and spawning of the offshore shrimp stock and coastal circulation conditions are invoked as possible sources of variability between cycles. The parameter μ d-3/yr-1/Pls. is recognized as a good estimator for assessing yearly immigration success of Pls. among cycles and localities. This parameter becomes statistically more robust, minimizing the above differences, when the numbers of days of Pls. absence detected in the two cycles are incorporated in the calculations. The monthly mean density of Pls. (μ d-3/month-1/Pls.) underwent significant interannual fluctuations (Mann-Whitney U-test, p = 0.001). While in cycle I there were three monthly abundance peaks, in cycle II only one peak was recognized. The correlation coefficient of this parameter in both cycles was low and inverse (r = -0.203). Nonetheless, both cycles exhibited similar values of maximum monthly mean Pls. density. The penaeid immigration process is a complex phenomenon, governed by physical factors and interspecific variability, that is further augmented when assorted sampling methodologies are applied in its study. The results here presented indicate the convenience of implementing long-term Pls. assessment in shrimp recruiting sites, and employing standardized methodologies in order to achieve a sustainable exploitation of this valuable resource. [ABSTRACT FROM AUTHOR]

Within the new classification of the superfamily Callianassoidea (cf. Sakai, 2010), six genera, including two new genera, with 13 species, including 7 new species and a previously reported form named herein as a new species, all based on material from the Gulf of Tonkin and the Red Sea, are examined in the present paper. In the Callianassidae Dana, 1852, subfamily Callianassinae, the genus Cheramus Bate, 1888 sensu Sakai (2010) includes C. anoplourus (Sakai, 2002) and C. malaccaensis (Sakai, 2002); the genus Notiax Manning & Felder, 1991 sensu Sakai (2010) includes N. bicauda sp. nov.; and the genus Trypaea Dana, 1852 sensu Sakai (2010) includes T. andamaniensis sp. nov., T. kovalewski sp. nov., T. spinoculata Sakai, 2005b, T. spinorostra sp. nov., T. tonkinae (Grebenjuk, 1975), and T. vietnamensis sp. nov. In the subfamily Callichirinae Manning & Felder, 1991 the genus Callichiropsis gen. nov., is established based on the type species Callichiropsis spiridonovi sp. nov. In the second family, Gourretiidae Sakai, 1999, the genus Paragourretia Sakai, 2004 includes P. zarenkovi sp. nov. and Paragourretia sp., and in the third family here examined, Micheleidae Sakai, 1992, the genus Micheleopsis gen. nov. is established on the basis of the type species Micheleopsis orlik sp. nov. [ABSTRACT FROM AUTHOR]

Twelve specimens of the western Atlantic shrimp, Farfantepenaeus aztecus (Ives, 1891), were caught between December 2009 and June 2010 by bottom trawl off Serik in Antalya Bay, Turkey. The species has probably been introduced in the eastern Mediterranean with ballast water. This is the first record of F. aztecus, and the second of a western Atlantic shrimp in the Mediterranean Sea. [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]

Dikerogammarus villosus possesses three pairs of pleopods. On all pleopods a single row of bifurcate clothespin setae is present on the inner margin of the proximal part of the inner ramus. The number and size of the clothespin setae are proportional to body length. The structure of the bifurcation suggests a sensorial function for these setae. Their possible role in the process of respiration (gas exchange) is discussed. [ABSTRACT FROM AUTHOR]

Agricultural channels can be important habitats for aquatic species inhabiting agricultural areas. However, water supply in agricultural channels can vary substantially with types of agriculture and irrigation/drainage system, and thereby affect the viability of local populations of aquatic species. In this study, we focused on the amphidromous freshwater atyid shrimp Caridina leucosticta. To clarify whether C. leucosticta utilizes agricultural channels as a habitat in relation to fluctuations in the water supply, we conducted a series of field surveys on the distribution of this shrimp in a rice paddy drainage channel (spring-fed channel) around the Furu River, central Japan, during July and December 2008. Large numbers of C. leucosticta had migrated into that drainage channel. Water from the adjacent rice paddies had disappeared by October, because irrigation was stopped, but the water level in the drainage channel was maintained by a supply of spring water. By mid-November the supply of spring water had almost disappeared, then the channel nearly dried up, and many shrimps were concentrated in an isolated water pool in the channel. Thus, habitat fragmentation of C. leucosticta occurred in terms of water (dis-)continuity. This water pool dried up completely by mid-December. We found many dead individuals of C. leucosticta in the dried-up area of the channel. These results indicate that agricultural channels can be an important temporal habitat for amphidromous freshwater shrimps, but that the drying-up of the channels can lethally affect migrating atyid shrimps. [ABSTRACT FROM AUTHOR]

The distribution of different species belonging to the freshwater shrimp genus Macrobrachium was studied along an altitudinal gradient in the Huitzilapan River, Veracruz, Mexico. Population surveys of M. heterochirus, M. carcinus and M. acanthurus were conducted along an 80 km long river stretch that started at 1045 m above sea level (asl) and ended at the estuary. In the dry and rainy seasons, sampling was conducted, at eight sampling sites along the river. The animals were collected with traps and casting nets. Five abiotic variables: temperature, salinity, water velocity, pH, and dissolved oxygen (DO) were measured. An altitudinal species segregation was observed: Macrobrachium heterochirus was most widely distributed in the dry season, from 1045 to 105 m asl, and most numerous at altitudes between 500 and 100 m; M. carcinus occurred at altitudes ranging from 280 to 5 m asl in both seasons; and M. acanthurus was restricted to the estuary below 5 m asl. Temperature decreased whereas water velocity increased with altitude, as was registered in both seasons. Our results indicate that seasonal differences shaped the distribution patterns of the three species. During the dry season, the distributions of the shrimp extended along the entire river, whereas in the rainy season their distribution was mainly in the lower area of river, and the main variables measured that have major influence in their abundance, seemed to be DO and water velocity. [ABSTRACT FROM AUTHOR]

Four specimens of a small-sized stomatopod, Taku spinosocarinatus (Fukuda, 1909), belonging to the family Takuidae Manning, 1995, were collected from intertidal dead coral rocks in southern Taiwan. This is the first record of this interesting cryptic stomatopod from Taiwan, and it is also the first record of the family from the island. [ABSTRACT FROM AUTHOR]

Abbreviated larval development is described and illustrated for Macrobrachium totonacum Mejía, Alvarez & Hartnoll, 2003, a recently described freshwater prawn with three larval stages. The study is based on laboratory-reared material. Females carry 18 eggs on average, with a maximum of 28. The average egg diameter is 2.1 mm. The first larval stage has sessile eyes, and all appendages are developed except the uropods; however, the chelae on pereiopods 1 and 2, and the pleopods, are non-functional. In stage 2 the eyes are articulated, and the chelae and pleopods are functional. In stage 3 the uropods are developed. The larvae are lecithotrophic in the first two stages, and start feeding in stage 3. The larval development of this species is compared with other Mexican and South American species of Macrobrachium with abbreviated development: it has the same number of stages as M. vicconi Román, Ortega & Mejía, 2000, another Mexican species. [ABSTRACT FROM AUTHOR]

While collecting Foraminifera shells from the bottom substrate around Pelješac Peninsula (southern Adriatic), the presence of Pontonia pinnophylax (Otto, 1821) in mussels, Pinna nobilis Linnaeus, 1758, living in Posidonia oceanica (L.) Delile sea grass meadows, was recorded. According to available data, it was obvious that detailed investigations of that species had never been made for the southern Adriatic. Ten samples of Pinna nobilis were obtained and only four specimens from the P. nobilis population were removed for investigation, from which eight individuals of Pontonia pinnophylax were isolated. The numbers and positions of the individuals were recorded. All of these were associated with their Pinna host in pairs, so the sex-ratio was 50% males and 50% females. Morphological study identified the left chela as the major chela in male shrimps. The largest host had the largest individuals of commensal shrimp. Total length appeared to be larger in male shrimps than in females. [ABSTRACT FROM AUTHOR]

The embryonic changes during the development of the freshwater prawn, Macrobrachium americanum are described from observations made on live embryos based on the percentage-staging method. Eggs were observed with a stereomicroscope to obtain descriptions of embryonic periods. This prawn has an incubation time of 18 days at 24°C. Ten periods are described and illustrated. A comparison of this developmental process with those of congeneric species is included. [ABSTRACT FROM AUTHOR]

Seasonal abundance, life history, and biochemical composition of Mesopodopsis orientalis were investigated based on samples collected over a period of one year in a tropical estuary, i.e., Cochin backwater. M. orientalis was recorded throughout the year and its peak abundance was observed during the monsoon period. The species produced more than one generation per year. The number of embryos carried by a single female ranged from 7 to 12, and was correlated with female length (P < 0.05), tending to increase with the size of the female. Egg size varied between 0.39 and 0.47 mm, with no correlation with length of the female, and size difference was observed in the same brood. Males and females attain sexual maturity after reaching a total length of 5 mm and 4.5 mm, respectively. With the exception of chlorophyll a, the environmental parameters, dissolved oxygen, salinity, pH, and water temperature do not have much influence on population density. The biochemical composition of the species reveals its high nutritional quality. Mature males and females showed higher protein contents than other stages, while carbohydrate content was high in immature stages, and lipid content was high in brooding females. [ABSTRACT FROM AUTHOR]

Mature female Macrobrachium rosenbergii in stage I of their ovarian cycle were divided into 17 groups (14 experimental groups and 3 controls) of 28 animals each. Animals in each experimental group were injected intramuscularly with 2-3 doses of serotonin (5-HT), dopamine (DA), octopamine (OA), spiperone (SP), or 5-HT plus SP, at four-day intervals from day 1 to 49. Five animals each in every group were sacrificed, respectively, at day 14, 25, and 49 to evaluate the gonadosomatic index (GSI) and oocyte diameters. The experimental groups that received the doses of 2.5 × 10-5, 2.5 × 10-6 mol of 5-HT/prawn, 2.5 × 10-5, 2.5 × 10-6, 2.5 × 10-7 mol of 5-HT/prawn plus 2.7 × 10-7 mol of SP/prawn, as well as SP alone at the dose of 5.4 × 10-7 mol of SP/prawn, exhibited significantly shorter periods of ovarian maturation and embryonic development, as well as increased GSI values and oocyte diameters, when compared with vehicle-injected and untreated control groups. In contrast, groups injected with DA and OA at similar doses showed decreased ovarian maturation, oocyte diameters, and embryonic periods, but no differences in GSI, when compared with control groups. For the number of eggs per spawn, the groups of animals that received 5-HT at doses of 2.5 × 10-5 and 2.5 × 10-6 mol/prawn, 5-HT at doses of 2.5 × 10-5 mol plus SP at 2.7 × 10-7 mol/prawn, 5-HT at 2.5 × 10-6 mol plus SP at 2.7 × 10-7 mol/prawn, and SP at a dose of 2.7 × 10-7 mol/prawn, yielded higher numbers than the control groups, and with a significant difference (P < 0.05). All DA and OA injected groups showed lower numbers of eggs when compared to the control groups. Eggs from all these experimental groups exhibited equally good quality both among each other and in comparison with control groups, as judged from the percentage of fertilized eggs. [ABSTRACT FROM AUTHOR]

A new species of penaeid, Metapenaeus motohi sp. nov. is described based on material from the Philippines. This new species is most closely similar to M. ensis (De Haan, 1844) from Japan in the morphology of the thelycum, but differs in that the rostral teeth mostly number 8-9, the P2, P3, and P5 are elongate, and the distal portion of the petasma forms a narrow lobule with a small genital pore. [ABSTRACT FROM AUTHOR]

The article offers information on the first record of the Jinga shrimp. It states that in the Levant Basin, eastern Mediterranean, nine species of alien penaeid prawns are found which include Marsupenaeusn japonicus, Metapenaeus monoceros, and Melicertus hathor. It notes that the mentioned specie of prawns are known from the Turkish coast. It discusses the characteristics and qualities of above mentioned prawns.

A new species of pontoniine shrimp, Periclimenes sandybrucei n. sp., is described and illustrated based on a specimen collected from deep water off northeastern Taiwan. The new species is allied to the “Periclimenes foresti Bruce, 1981” species group but can be readily distinguished from all the known species of this group by bearing three pairs of dorsolateral spines on the telson, and having the propodi of the third to fifth pereiopods unarmed. [ABSTRACT FROM AUTHOR]

A new species of rhynchocinetid shrimp, Cinetorhynchus brucei sp. nov., is described and illustrated on the basis of two specimens from Kume-jima Island, Ryukyu Islands, southern Japan. The absence of an arthrobranch on the second and third pereopods links C. brucei to C. manningi Okuno, 1996, known from the western Atlantic Ocean, but the present new species differs from the latter on account of the length of stylocerite, the development of the podobranch of the second maxilliped, and the armature of the meri of the ambulatory pereopods. [ABSTRACT FROM AUTHOR]

Leontocaris Stebbing, 1905 is a genus of hippolytid shrimps with a distinctive major pereopod having a blade-like dactylus closing on a massive propodus, together supported by extensible folded proximal articles. A new species, Leontocaris alexander, is described from south-eastern Australia bringing the total number of species to eight. A phylogeny of the species demonstrates L. alexander is similar to L. paulsoni Stebbing, 1905 from South Africa and L. pacificus Zarenkov, 1976 from the south-eastern Pacific. With less confidence, L. amplectipes Bruce, 1990 and L. yarramundi Taylor & Poore, 1998 from south-eastern Australia and L. lar Kemp, 1906 from north-western Atlantic are similar, and L. bulga Taylor & Poore, 1998 from south-eastern Australia and L. vanderlandi Fransen, 2001 from the Indian Ocean are sister taxa. The phylogeny does not reflect geographic distribution. [ABSTRACT FROM AUTHOR]

Neopontonides brucei, a new species of pontoniine shrimp is described from Brazil and the west coast of Panama. The Panamanian specimens were probably associated with gorgonians. [ABSTRACT FROM AUTHOR]

A new genus, Sandimenes nov. gen., is established for Periclimenes hirsutus Bruce, 1971a based mainly on its unusual character of the dense, long tufts of setae on the ventral surface of the ambulatory propodi, and the general hirsuteness of the body and appendages. The genera erected or removed from the synonymy of Periclimenes after Bruce's (1994) monograph on the Indo-West Pacific genera of the Pontoniinae are reviewed, and a key to those genera closely similar to Periclimenes is provided. [ABSTRACT FROM AUTHOR]

Sandyella gen. nov. is erected for two eastern Pacific pontoniine shrimps, Chacella tricornuta Hendrickx, 1990 and Chacella mclaughlinae Li, 2006. The new genus can be clearly distinguished from all other pontoniine genera by the unique dorsal ornamentation of the carapace and the dorsal surface of the first three abdominal somites; the straight, unarmed, anterior margin of the carapace; and the greatly produced anterior distodorsal margin of the eyestalk. [ABSTRACT FROM AUTHOR]

Rose shrimp (Parapenaeus longirostris) and Norway lobster (Nephrops norvegicus) are the two main target crustaceans for the demersal trawl fleet in the international waters of the Aegean Sea. In the present study, selectivity data were obtained for these two species in commercial codends (300 MC is 40 mm polyethylene codend with 300 meshes on its circumference) and two newly designed types, known as a narrow codend (200 MC is 40 mm polyethylene codend with 200 meshes on its circumference — 33% reduced) and square mesh top panel codend (SMTPC is constructed as 150 diamond meshes on the lower and 75 square meshes on the top panel), respectively. These three types of codends were tested using the covered codend method. Trawling was carried out at depths ranging from 269 to 426 m onboard a commercial vessel in August 2004. Selection parameters were obtained by fitting a logistic equation using the maximum likelihood method. The rose shrimp, in terms of weight, was the most abundant marketable species, with catch per hour values of 19.1, 16.0, and 15.0 kg in 300 MC, 200 MC, and SMTPC, respectively. Results of the selectivity analysis indicate that the commercially used 40 mm nominal mesh size PE codend is rather unselective for these species. In general, narrow and square mesh top panel codends have relatively higher L50 values than the commercial codend. However, the differences are significant only for rose shrimp, but not for Norway lobster. It is concluded that despite the improvements in selectivity, the codend modifications 'narrow' and 'square mesh top panel' were not sufficient to release immature specimens of either species, at least not when using the 40 mm PE standard netting. [ABSTRACT FROM AUTHOR]

Feeding in Dikerogammarus villosus (Sowinsky, 1894) males was observed in the field and recorded on video in the laboratory. The following feeding modes were recognized: detritus feeding, grazing, particle feeding, coprophagy, predation on benthic and free swimming invertebrates, predation on fish eggs and larvae, as well as feeding on byssus threads of the zebra mussel, Dreissena polymorpha (Pallas, 1771). The feeding methods are described and illustrated with screenshots of video recordings. The very flexible feeding modes of D. villosus, which make diet switches possible, form a trait that must be an important factor in the invasion success of this Ponto-Caspian gammaridean species, and may thus explain for a great deal its high ecosystem impact. [ABSTRACT FROM AUTHOR]

The holotype specimen of the pontoniine shrimp, Periclimenaeus spinicaudata Bruce, 1969, is described and illustrated for the first time. It is found to closely resemble Paraclimenaeus fimbriatus (Borradaile, 1915) and is transferred to the genus Paraclimenaeus Bruce, 1988b. Apopontonia dubia Bruce, 1981b is found to be a junior synonym of Paraclimenaeus spinicauda (Bruce, 1969). The pontoniine genera Apopontonia Bruce, 1976, Paraclimenaeus Bruce, 1988, and Climeniperaeus Bruce, 1996 are re-defined. Apopontonia is restricted to the single species Apopontonia falcirostris Bruce, 1976. Apopontonia orbitospinata Bruce, 2001, is transferred to the genus Climeniperaeus, together with Periclimenaeus truncatus (Rathbun, 1906) and Periclimenaeus orbitospinatus Bruce, 1969. Apopontonia seticauda Bruce, 2008, is also transferred to the genus Paraclimenaeus Bruce. [ABSTRACT FROM AUTHOR]

The article cites a study which examines the presence of the pontoniine shrimp or tuleariocaris holthuision the pacific coast of Panama. It investigated that it female species were investigated in the Coiba National Park which confirmed its presence in the region and significantly increasing. They were found attached to the spines of a black sea urchin, which is their only known host in the eastern pacific. It also determined that they include four species all associated with sea urchins, including Tuleariocaris holthuisi, Tuleariocaris Neglecta, Tuleariocaris sarec and Tuleariocaris Zanzibaricu.

The deep water rose shrimp, Parapenaeus longirostris is a commercial species for the trawl fleet that operates in the Gulf of Alicante. Despite its importance, there were no biological studies on the species for that area. This study presents results on the life cycle of the species, shedding light on certain crucial aspects. Data were obtained from monthly samples taken from commercial catches landed in the port of Santa Pola from 2001 to 2006. The fisheries in the studied area show a decreasing trend, both in number of vessels targeted on the species, and in landings, since 2001. The species shows a sexual size dimorphism, with a negative allometry of relative growth that is more pronounced in males and thus results in lower sizes of males than of females. Estimate produced from VBGF parameters gave higher K values for males than for females, indicating that males would reach 13.2 mm CL in the first year and females 14.8 mm CL, which would represent a maximum life expectancy of 4 and 6 years, respectively. The reproductive period, based on the percentages of maturity and GSI development, was found to range throughout the year, with some peaks of activity especially in summer. The size at first maturity (L50) of 25.6 mm for females indicates that maturation will have to occur from the second year of life. [ABSTRACT FROM AUTHOR]

Reproductive biology and population dynamics of the freshwater shrimp, Atyaephyra desmarestii were studied in Tunisia. In the reserve dam lake of Sidi Salem (northern Tunisia), a total of 7200 specimens was collected in monthly sampling over two years, from August 1996 to July 1998. Each sample of shrimps was sorted in the laboratory and separated into juveniles, males, and females. The presence of ovigerous females during spring and summer indicated that reproduction of Atyaephyra desmarestii is seasonal, starting in March and ending in August, followed by a sexual rest of six months, from September to February. The peak of reproductive females occurred in April and undifferentiated juveniles were present over the year. Fecundity was positively correlated with the size of ovigerous females. The sex-ratio underwent seasonal and monthly fluctuations, related to the size of the shrimp. Females were less numerous than males between 15 and 20 mm, but dominated beyond 20 mm. Analysis of the size-frequency distribution allowed to identify ten cohorts, four in the first sample of August 1996, and the other six during the rest of the sampling period. Life span was estimated between 13 and 16 months, based on 2 cohorts per season, one in spring and the other in summer. Cohorts appearing in May of each year, quickly reached sexual maturity and became reproductive after three months at just 17-18 mm total length. [ABSTRACT FROM AUTHOR]

A new species of freshwater atyid shrimp, Caridina gueryi sp. nov. from Santo Island, Vanuatu, is described and illustrated herein. C. gueryi is similar to Caridina longirostris H. Milne Edwards, 1837, by its long rostrum, small eggs are of similar size, the termination of the telson in a posteromedian projection, the preanal carina with a distinct spine, and, in males, the appendix interna being clearly visible on the endopod of the first pleopod. However, both species can easily be distinguished as C. gueryi sp. nov. has a long stylocerite, always overreaching the basal segment of the antennular peduncle and lacks subapical teeth on the rostrum. [ABSTRACT FROM AUTHOR]

This study investigates the differences in selectivity of commercially used 44 mm mesh size single and double codends for the deep-water rose shrimp, Parapenaeus longirostris by using the covered codend method. Experiments were conducted on the commercial fishing grounds of Kuşadası Bay and Sığacık Bay of the eastern Aegean Sea, between 3 and 27 October 2007. Twenty-four hauls were carried out, eleven with single and thirteen with double codends. The mean fifty-percent retention length (L50) values of double and single codends were found to be 12.0 ± 0.09 and 16.9 ± 0.08 mm, respectively. Selection range (SR) values for double and single codends were 4.0 ± 0.05 and 5.9 ± 0.09 mm, respectively. Significant differences were found between L50 and selection factor (SF) values of double and single codends (p < 0.05) for the deep-water rose shrimp. However, towing duration and catch size did not have any significant effect on these parameters (p > 0.05). This work shows that the use of 44 mm mesh size knotless polyethylene (PE) diamond mesh codends is by itself destructive for immature shrimp. The use of narrower netting around it to establish a double codend further decreases the already insufficient selectivity for this species. [ABSTRACT FROM AUTHOR]

Several specimens of Ascidonia flavomaculata were collected during experimental fishing trials along the southern coast of Portugal. All specimens were associated with the solitary ascidian, Phallusia mammillata. The pontoniinae shrimp, A. flavomaculata is here recorded from the Portuguese coast for the first time, extending the species' known distribution range further north along the coast of the eastern Atlantic Ocean. [ABSTRACT FROM AUTHOR]

This study aims to assess the selectivity of square and hexagonal mesh codends for the deep water rose shrimp, Parapenaeus longirostris. Experiments were conducted in Kuşadası Bay and Sığacık Bay, eastern Aegean Sea, between 30 September and 25 October 2007 with a commercial stern trawler. The covered codend technique was used for controlling the escapees and selectivity parameters were estimated by maximum likelihood over a logistic model. The selectivity parameters for individual hauls were estimated using the software CC2000, whereas mean selection curves of the codends were estimated by using Fryer's model, taking into account the between-haul variation using the ECModeller software. The mean fifty percent retention length (L50) values of square and hexagonal mesh codends were estimated as 16.7 mm ± 0.07 and 17.4 mm ± 0.05, respectively. Selection range (SR) values were 6.5 mm ± 0.11 in square and 6.2 mm ± 0.15 in hexagonal mesh codend. Although L50 and SR values of the two different mesh shape codends are close to one another, L50 values of neither codend provides a satisfactory selection, considering the 21 mm length at first maturity (LFM) of this species. However, the hexagonal mesh codend can be used as an alternative for the same mesh size diamond mesh codend in targeted rose shrimp trawl fishery. [ABSTRACT FROM AUTHOR]

The present paper reports 13 species of shrimp from Dongtou Island, Zhejiang Province, in the East China Sea. Among these, a species of alpheid, Alpheus euphrosyne De Man, 1897, which is very similar to the typical subspecies, is recorded for the first time from Chinese waters; one species of penaeid, Metapenaeus affinis (H. Milne Edwards, 1837), is recorded for the first time from Zhejiang; and six other species are recorded for the first time from Dongtou Island with certainty. [ABSTRACT FROM AUTHOR]

Life-history traits and exploitation of the red shrimp, Aristeus antennatus (Risso, 1816) (Decapoda, Aristeidae) on the Algerian slope (south-western Mediterranean) have been studied through monitoring of the commercial trawl fishery between 1999 and 2006 at two different ports on the west coast, as well as through monthly biological sampling of these catches from April 2005 to September 2006. This information was completed with data from experimental bottom trawls, carried out in the area during 2003 and 2004. A continuous increase of the trawl fleet and the landings of red shrimp during the study period were detected. Although this fishery takes place only in a very limited part of the distribution range of the species (around depths of 300-525 m), experimental data gave a continuous increase of red shrimp density from 400 to 700 m. The Algerian fishery showed seasonal variation in yields, with a maximum during summer and autumn, although the average daily yields were clearly higher than those from other western Mediterranean fisheries. Experimental trawls detected two distinct demersal assemblages on the slope grounds of the study area, separated approximately by the 400 m isobath. Decapod crustaceans constituted the dominant group in these assemblages, with the pink shrimp (Parapenaeus longirostris (Lucas, 1846)) and the red shrimp as their most important and abundant species, and either shallower, or deeper than that isobath, respectively. Both species of shrimp showed one of the highest abundance indices estimated in the Mediterranean yet. Fishes were also important in these assemblages, the composition of which suggested high species diversity, with complex and extensive trophic webs. Monthly length frequency distribution of commercial catches showed that the carapace length (CL) of female shrimps ranged between 18 and 65 mm, while males ranged from 16 to 41 mm CL. Females represented more than 70% of the individuals caught, although the sex-ratio by length showed a predominance of males for individuals ≤18 mm CL and of females for individuals ≥25 mm CL, while their monthly development also showed a predominance of females from April to September and a similar proportion of sexes from October to March. Ripening gonads of females were mostly found from June to August, and the gonadosomatic index also showed a clear peak during this period. The length at which 50% of females were mature was estimated as 27.7 mm CL. The length-weight relationship showed a strongly negative allometry for both sexes (b = 2.4), while the Von Bertalanffy growth parameters differed greatly between them, with values for maximum theoretical size and for the growth coefficient of females (L∞ = 70.6 mm CL and k = 0.5 year-;1, respectively) being higher than those for males (L∞ = 43.0 mm CL; k = 0.3 year-;1). The growth performance index (Φ) for females (3.4) was also higher than that for males (2.7). [ABSTRACT FROM AUTHOR]

The south of Patagonia is characterized by its semi-arid weather and numerous small, temporary and permanent shallow ponds. The aquatic crustaceans of these water bodies are characterized by their endemism and species richness. The present study was done in the surroundings of Punta Arenas (53°S, Chile), and included six shallow ponds. Samples for conductivity, total dissolved solids, chlorophyll, and crustacean zooplankton as well as littoral species of crustacea were collected. Our study revealed that Branchinecta gaini Daday, 1910 occurred at low conductivity (0.55 mS/cm), and low total dissolved solids (0.28 g/l) and chlorophyll (2.70 μg/l) concentrations, such compared to sites without fairy shrimp populations, that had significantly high conductivity (3.58 mS/cm), and high total dissolved solids (1.80 mg/l) and chlorophyll (12.80 μg/l) concentrations. The results partially agree with the first descriptions of Patagonian water bodies that indicated the presence of fairy shrimps in low conductivity waters. The observations of the presence of B. gaini and other associated microcrustaceans are similar to descriptions of unpolluted water bodies in Antarctica, and those results would support the observations of the present paper. Other reports on fairy shrimp habitats mentioned a wide range of both salinity and trophic status. Other ecological and biogeographical topics on fairy shrimps are also discussed. [ABSTRACT FROM AUTHOR]

The article presents an observation study on a freshwater prawn, Macrobrachium rosenbergii, a specimen from Madagascar. According to previous researches, 12 species of Macrobrachium were recognized in this country and for such reason, Madagascar becomes an attraction for several unique fauna and flora species. From the results of the morphological study conducted by Wowor & Ng in 2007, prawn population inhabiting the east area of Huxley's line falls under Macrobrachium rosenbergii , while the population in the west is attributed to Macrobrachium dacqueti. A summary of information regarding the investigation on the identities of freshwater prawns in Madagascar is also presented.

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]

Investigations on reproductive aspects of the ridgetail prawn, Exopalaemon carinicauda were made in the Hampyong Bay of Korea from January 2003 to December 2004. Males and females comprised 31.6% and 68.4% of the total sample, respectively. There was a predominance of females in the sex ratio. Females progressively dominated the larger size classes. Female maturity was determined by the size of ovigerous females and of females with maturing ovary. The size at which 50% of females are mature is estimated as 14.97 ± 4.63 mm CL. The main breeding season, from June to August, coincided with higher gonadosomatic indices. A significant difference in ovarian weight between females with non-eyed and with eyed egg stages was found. In this season, ovaries rematured during embryonic development, indicating a potential for multiple ovulations. Based on the incubation time of the embryos, females seemed to have at least two broods per year. Brood size showed a positive allometry to female body size with no apparent egg loss during incubation. The egg volume increased by 91% from 0.78 ± 0.17 mm3 at non-eyed eggs to 1.50 ± 0.34 mm3 at eyed eggs. Based on dry weight, an egg batch averaged 14% of female weight, indicating an investment in egg production similar to that in other marine shrimps, but lower than that of freshwater shrimps. [ABSTRACT FROM AUTHOR]

The article features two of the Sala y Gomez's Periclimens specimens including Periclimenes alcocki and Periclimenes pseudalcocki. It notes that at present, there are 13 closely similar species of deep water shrimps characterized by the presence of three or more pairs of dorsal telson spines and biunguiculate dactyls on the ambulatory pereiopods. Periclimenes alcocki is broken into two fragments at the third/fourth abdominal somites and lacks all perceiopods. Among its characteristics include the telson that has four pairs of dorsal spines, the carapace which is intact, and the cornea which is well developed, large, and globular. The characteristics of Periclimenes pseudalcocki include intact body and rostrum intact, dactylus with accessory tooth minute, and large dorsal telson spines.

The article presents a study on the meristic character in wild postlarvae of the Litopenaeus Vannamei, a white shrimp, and its implication to fisheries and aquaculture. It notes that the indiscriminating exploitation of wild shrimp postlarvae in offshore areas to be stocked in aquaculture ponds affected the industrial fishery. It discusses the importance of applying meristic characters to achieve a desirable shrimp that can be carried either into large aquaculture ponds or in semi-enclosed estuarine sites. It states that the presence of a certain number of dorsal spines in white shrimp's immigrating planktonic postlarvae is suitable meristic character in defining the larval stage needed for the nursery grounds.

We here report the isolation of haemocyanin, the crustacean oxygen transporter, from the haemolymph of the Chinese shrimp, Fenneropenaeus chinensis. We employed a Superdex 75 column, and the purified protein was demonstrated as homogeneous by Native-PAGE. The molecular mass of the purified haemocyanin was estimated to be 450 kDa using SDS-PAGE. The subsequent 2-DE suggested that it would be composed of three different subunits of 75-76 kDa each. Primary structure determination was performed by LC-ESI-MS and the data obtained were compared with the NCBI database. The result showed that these three subunits are identical to a partial fragment of haemocyanin from Litopenaeus vannamei. This research could be relevant to obtain pure haemocyanin, and will be helpful for further study on the structure and function of this large molecule. [ABSTRACT FROM AUTHOR]

The article focuses on a new record of the ogyridid shrimp or ogyrides mjoebergi which were obtained by snorkelling over sandy bottoms at a depth of 5 meters along the Levantine coasts of Turkey. The specimens, including the one photographed, are preserved in 4% formaldehyde and deposited in the Museum of the Faculty of Fisheries, Ege University, Bornova-Izmir. A review of inventory studies relevant to this species indicates, that Ogyrides mjoebergi constitutes a new record.

Twenty-nine species of marine decapod Crustacea, specimens of which are deposited in the collections of the Muséum National d'Histoire Naturelle, Paris, are reported for the first time from the Lattakia area in Syria. The number of Decapoda currently known from this part of the Syrian coast is 88, of which 15 are Lessepsian migrants. Among the latter, four are reported for the first time from Syria: Alpheus lobidens De Haan, 1849, Ixa monodi Holthuis & Gottlieb, 1956, Micippa thalia (Herbst, 1803), and Thalamita poissonii (Audouin, 1826). The main sites for prospection are, from north to south: Al Hamam Island, Al Bdroussieh, Al Manarah, Om Tior, Bourj Islam, Ash Shamieh, Ibn Hani (Bourj Al Kassab), Alsahta'e Alazrak, Afamia, and the port of Lattakia. [ABSTRACT FROM AUTHOR]

This study examines the impact of shrimp trawling on the multi-species shrimp and prawn fishery in the northeastern Mediterranean. Fishing trials were carried out on a commercial prawn trawler between 18 and 23 September 2006. Data were collected with a conventional trawl net, designed specifically for prawns. During six valid trawl hauls, 32 species were caught in total and of the 17 species regarded as commercially valuable, individuals of all sizes of 12 species and those of the relatively larger sizes of 5 species were retained. The other 15 species were discarded as these are regarded as non-commercial due to a lack of market demand. The discard ratio was calculated as 2.37 : 1 for this fishery. The length-frequency distribution of the targeted penaeid prawn, Marsupenaeus japonicus, shows one peak at about 33 mm CL, and the larger specimens, over 35 mm, are all females (25%). However, the also targeted Penaeus semisulcatus shows two major peaks, at 29 and 39 mm CL, and the approximate size ranges connected with those peaks extend from 26 to 32 mm and from 36 to 40 mm CL, respectively; larger specimens, over 34 mm, are all females (37%). The female-male ratio was 1.07 : 1 for M. japonicus and 1.99 : 1 for P. semisulcatus. In the framework of by-catch and discard evaluation, this fishery should be defined as having high by-catch and discard rates. For this reason, gear-based and management-based solutions or measures should be developed to secure those resources for the future, and also to decrease the impact of fisheries on non-targeted species and their stocks. [ABSTRACT FROM AUTHOR]

A new freshwater ostracode, Cyclocypris vinyardi n. sp., belonging to the family Cyclocyprididae is described from a slow flowing rheocrene spring in Nevada, U.S.A. The new species is distinguished from the other 12 extant species of the genus in the United States based on the double rows of pore openings on the anterior end of the carapace, differences in the shape of the hemipenis, and asymmetry in the clasping organs. [ABSTRACT FROM AUTHOR]

During a study on the ecology and biology of the fan mussel, Pinna nobilis along the northern and eastern coasts of Tunisia, the presence of the shrimp, Pontonia pinnophylax and the crab, Nepinnotheres pinnotheres (Decapoda) associated with this bivalve, was recorded. The shrimp was collected only in the lagoon of Bizerte, whereas the crab was found exclusively at Stah Jaber (close to the fishing port of Monastir). P. nobilis was occupied by Pontonia pinnophylax in 23.3% of the samples and the associated shrimp population was dominated by males (63.6%). Shrimp couples were generally encountered inside the large pinnids, and the size of the shrimps increased with that of the host. P. nobilis was occupied by Nepinnotheres pinnotheres in 56.7% of the cases. The highest numbers of crabs were recorded in the oldest pinnids. The sex-ratio of the associated crab population was male-biased, 62.5% of the population being males. A morphological study of the two associated species revealed some features worth noting. In the female shrimp, distinguished by the right chela in the second pair of pereiopods being definitely larger than the left, the length of this appendage (both right and left) increased with individual size, but these two variables were found independent in the male shrimp. Concerning Nepinnotheres pinnotheres, the length of the two chelae of the first pair of pereiopods increased with that of the animal's body in both sexes. [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 size structure of the commercially important rose shrimp, Parapenaeus longirostris, was compared between populations in the Sea of Marmara and the Aegean Sea. The analysis was based on data collected during trawl selectivity surveys carried out in November and December 2006. Growth showed no similar pattern, and in additions differences were found in length frequency distribution, sex ratio, and recruitment pattern of the P. longirostris populations in these two areas. [ABSTRACT FROM AUTHOR]

Bioluminescent behaviour of deep-sea decapods is difficult to study under long-term laboratory maintenance, because most deep-sea organisms suffer from high mortality in such conditions. The objective of the present study was to determine the survival of the deep-water pandalid shrimp, Heterocarpus sibogae De Man, 1917 and its ability to produce bioluminescence when maintained in the laboratory. H. sibogae exhibited bioluminescence by emitting two streams of blue luminous secretions from the mouth when disturbed. The luminous material decayed rapidly and disappeared in seconds. Shrimps retreated from the luminous region immediately after secretion, suggesting that bioluminescence is a defence response. Under laboratory conditions, H. sibogae can produce luminous secretions for at least 43 days of maintenance. Maximum emission time was recorded in a non-ovigerous female that reached 634 seconds. Males and non-ovigerous females showed a similar average emission time of about 30 seconds. Ovigerous females, however, produced significantly longer emissions with an average of 103 seconds, suggesting that these may contain larger amounts of the key chemical for bioluminescence, coelenterazine, than males and non-ovigerous females do. [ABSTRACT FROM AUTHOR]

This paper describes variation in morphological characteristics, seasonal density, size-biomass relations, fecundity, and egg development of the freshwater shrimp, Caridina nilotica (P. Roux, 1833) from its type locality, the Lower Nile river in Egypt. Morphological characteristics were in line with a recent re-description of the species and with earlier descriptions of C. nilotica (C. nilotica var. typica, C. nilotica nilotica) from the river Nile with exceptions regarding the ranges of the number of teeth on the rostrum and spines on the telson. Sexes could be distinguished from a size of 12 mm; from a body size of 20 mm, ovigerous females were found. The number of eggs per female ranged from 43 to 147 and was positively correlated with body length. The sex ratio was female-biased and constant over the sampling period. Females grow larger than males. The development of gonads and eggs showed some seasonal variation. During the whole sampling period, all life cycle stages (juveniles, adult males, and non-ovigerous as well as ovigerous females) were present. Density was positively related with water temperature. [ABSTRACT FROM AUTHOR]

This study describes the relationships of the body length and the population density of the yellowleg shrimp, Farfantepenaeus californiensis (Holmes, 1900) with differences in depth, in two coastal lagoons and on the adjacent continental shelf of the Gulf of California. The Agiabampo and Navachiste lagoon systems are located on the east side of the Gulf of California, bordering the states of Sonora and Sinaloa, Mexico. The environmental conditions of the lagoons are stable, with salinities of 35.5 to 38 psu over an annual cycle. Before sampling, the bathymetry of the lagoons was studied. From December 2001 to January 2003, sampling of shrimp was performed monthly for five consecutive days. The preference of shrimp for a particular depth, according to their size, was examined and the density of shrimp at selected depths was compared. Large differences in body size between the samples at selected depths were found. The density of the shrimp did not correspond with depth, but small shrimp showed greater mean densities. The cues used by species for offshore movement may largely be size-related. Juveniles moved down the estuary and out to sea as they grew. Depth may be involved in the migration of shrimp from lagoons with stable salinity gradients. Migration requires that the shrimp respond to some cue associated with size or to some change in their environment. The conclusion in this study is, that the yellowleg shrimp, F. californiensis responds to differences in depth, depending on its size, which is independent of whether it is inside the lagoon or in an open marine habitat. [ABSTRACT FROM AUTHOR]