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The first evidence of the predation of brittle stars, Ophiothela sp. (Ophiotrichidae), by the palaemonid shrimp Phyllognathia simplex Fujino, 1973 (Palaemonidae), is presented based on a single observation accompanied by in situ photographs taken while scuba diving in Bali, Indonesia, also being the first ever observation of the feeding behaviour in this uncommon shrimp species. In addition, in situ photographs of three ovigerous females tentatatively identified as P. cf. simplex from southern Florida, U.S.A., suggest that P. simplex or a closely related species may be present in the western Atlantic. This is the first photographic evidence of the presence of the genus Phyllognathia Borradaile, 1915 in this part of the world. [ABSTRACT FROM AUTHOR]

Morphometric relationships and condition factors are essential for understanding any marine species' development process, which aids in designing appropriate strategies for management and articulating their balance in the ecosystem — and this includes shrimps. Since only a few studies on these characteristics have been done in Penaeus semisulcatus over the last thirty years, constant updating of these criteria is required to successfully manage the shrimp fishery in Palk Bay. The CL-TW relationship demonstrates negative allometric growth in both males and females, whereas the TL-TW relationship exhibits positive allometric growth. In this present investigation, significant differences in slopes and elevations of the carapace length-total weight, total length-total weight, carapace length-total length, and total length-carapace length have been observed between sexes; considering the condition factors shown in the present investigation, the shrimps in Palk Bay were in good growing condition. This study has demonstrated that updated information on morphometric relationships would help fishery managers effectively manage the fisheries. [ABSTRACT FROM AUTHOR]

Sustainable fishing technology for shrimp in Cape Verde's semi-deep waters. A 20-year cooperative journey: from surveying to sustainable exploitation of a virgin resource. [ABSTRACT FROM AUTHOR]

During a series of irregular visits to Inhaca Island, Mozambique in the years 1982-1987, J.H.C. Walenkamp, often aided by students and staff of the Faculty of Biology in Maputo, made extensive collections of littoral and infralittoral invertebrates. Among the extensive collections of Brachyura, several caridean shrimps were encountered, upon which we herein report. Cuapetes cf. ensifrons is recorded from Mozambique for the first time. [ABSTRACT FROM AUTHOR]

A new species of deep-sea shrimp, Bathypalaemonella liui sp. nov., is described from the seamount of the South China Sea at a depth of 759–1117 m. Bathypalaemonella liui sp. nov. is most similar to B. hayashi Komai, 1995 and B. serratipalma Pequegnat, 1970 for the flexor margin of the major second pereopod bearing a row of tubercles. Important morphological characters which differentiate the present new species from B. hayashi and B. serratipalma are the length of the rostrum, which is far exceeding the scaphocerite, and the dactylus of the posterior three pereopods, which only bear one pair of accessory spines. Moreover, the genetic divergences of the COI and 16S rRNA genes from these two congeners analysed, clearly support the new taxon. [ABSTRACT FROM AUTHOR]

The green tiger shrimp, Penaeus semisulcatus , is a commercial species supporting important fishery along the Palk Bay coasts. It is a much sought-after seafood commodity influencing the livelihood of the local fishers. This study aims to investigate the fecundity of the species in relation to its morphometry. Fecundity is an index of reproductive capacity used to calculate a stock's reproductive potential and the egg's survival. The absolute fecundity of the shrimp ranged from 26 100 to 750 000 ova alive per female, and the mean absolute fecundity from 59 100 to 583 000 ova alive per female. The relationship between fecundity and the morphometric measurements showed a positive exponential correlation. One-way ANOVA indicated a significant difference in the different size classes' carapace length, total weight, ovary weight, absolute fecundity, stomach weight, and gastrosomatic index. There was no significant difference between the relative fecundity and the gonadosomatic index. This study provides insight into the reproductive potential of P. semisulcatus for efficient management of the resource in Palk Bay, Tamil Nadu, India. [ABSTRACT FROM AUTHOR]

In Mexico, the spiny lobster fishery is well established but this is not the case with the slipper lobster fishery. For a sustainable fishery, many biological traits must be known, one of which is growth. The objective of the present study was to probe the multi-model approach to identify the curve that best describes the growth of Evibacus princeps from the Gulf of California. Specimens were collected aboard commercial trawlers during the industrial shrimp fishing season (October 2021-March 2022) at depths ranging from 10 to 55 m. Five versions of the Schnute model (including the Von Bertalanffy model) were applied and the best model was selected using the Bayesian information criterion. The estimation of an average model was performed because no model obtained 90% of the evidence. E. princeps from the Gulf of California exhibit an indeterminate growth pattern. [ABSTRACT FROM AUTHOR]

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]

Penaeus semisulcatus is a large growing species, attaining a maximum size of about 250 mm in total length. It is more resistant to white spot syndrome virus (WSSV) than other cultivable penaeid shrimps, which makes it a potential candidate for culture. The present study evaluated the influence of a different feeding rate of polychaete worms on the gonad development of male P. semisulcatus under captive conditions. P. semisulcatus sub-adults were obtained in the wild. The shrimps were fed with three different concentrations of polychaete worms, viz., ad libitum (T1), 5% of body weight (BW) (T2) and 10% BW (T3), and fresh sardines were fed as a Control (C) diet, all for a period of 60 days. Sampling was done once in 15 days and the bio-growth parameters were recorded. The gonads were harvested for histological analysis. The maximum weight gain (10.19 g), mean weight gain percentage (85.20%), mean daily growth rate (DGR) (0.169833) and mean specific growth rate (SGR) (0.45) were found in shrimps fed with the polychaete worm diet at 5% BW. The estimated bio-growth parameter values were statistically significant when analysed using One way ANOVA (P < 0.05). Histological sections of the testis showed variations in the development of the gonad between the treatments with different feeding rates during the 60 days trials. Indeed in all aspects, the development was higher in shrimps fed with polychaete worms at 5% BW. It can be concluded that feeding polychaete worms at 5% BW created a regime able to improve growth rates, gonad maturation, and quality in the development of the captive male brood stock. [ABSTRACT FROM AUTHOR]

Fishery and population characteristics of the Indian white shrimp, Penaeus indicus , were studied in Pulicat Lake, on the southeast coast of India, using the FiSAT software package. The asymptotic length ( L ∞ ), growth coefficient (K) and arbitrary origin of growth (t 0) were estimated by the ELEFAN method to be 16.18 cm, 0.60 year−1 and −0.18 year, respectively. The asymptotic length ( L ∞ ) was calculated as 16.09 cm using the Wetherall method. The growth performance index (Ø′) was found to be 2.19. The mortality parameters Z , F and M were computed to be 3.85, 2.30 and 1.55 year−1, respectively. The pattern of recruitment was observed to be year-round, with a peak from June to September. The total stock, annual catch and exploitation rate for P. indicus were estimated to be 1518.43 tonnes, 809.3 tonnes, and 0.59 year−1, respectively. The estimated Maximum Sustainable Yield (MSY) was found to be 131.95 tonnes less than the annual catch. The stock of P. indicus was found to be over-exploited, so it is suggested that the effort level be reduced by 16.3% in order to sustain this resource in Pulicat Lake. [ABSTRACT FROM AUTHOR]

A re-examination of Periclimenaeus trispinosus Bruce and P. orbitospinatus Bruce (Crustacea: Decapoda: Pontoniinae). A new deep-sea pontoniine shrimp (Decapoda, Palaemonidae) of the ' Periclimenes foresti Bruce, 1981' species group from Taiwan. Re-evaluation of the genera Apopontonia Bruce, 1976, Paraclimenaeus Bruce, 1988 and Climeniperaeus Bruce, 1996. Pontoniine shrimps (Decapoda: Palaemonidae) from the island of Socotra, with descriptions of new species of Dactylonia Fransen, 2002 and Periclimenoides Bruce, 1990. [Extracted from the article]

Integrative taxonomy confirms the presence of the enigmatic Lysmata olavoi Fransen, 1991 (Decapoda: Lysmatidae) in the Mediterranean Sea. - The shrimp specimens collected agree well with the description, illustrations, and colour pattern given for the species (Fransen, 1991). In 1991 Charles Fransen described and figured a new species of caridean shrimp, I Lysmata olavoi i (Lysmatidae), based on 29 specimens caught off the island of Pico, the Azores (26 specimens) and off Salvage Islands (3 specimens), in the eastern Atlantic Ocean (Fransen, 1991). The authors do not find a reasonable explanation for the sudden appearance (in small numbers) of I L. olavoi i as a bycatch species in shrimp-traps targeting I Plesionika edwardsii i (J. F. Brandt, 1851) in the waters off the island of Tenerife. [Extracted from the article]

Charybdis (Archias) omanensis septentrionalis Türkay & Spiridonov, 2006, has recently been recorded from the Arabian Sea, while the first record of the species was from the Red Sea. The specimens were collected in a shrimp trawl from a depth of 65-68 metres from the southwest coast of the Arabian Sea, off Kerala, India. The species size ranged between 17 and 37 mm carapace width, from 11 to 22.5 mm carapace length and in total weight between 0.39 and 5.53 g. The interrelationships between various morphometric characters, viz., carapace width and length and chelar propodus length and height in males, as well as carapace width and length and abdominal width and length in females, were estimated for the species and it was found that most relationships are positive and highly significant. In the carapace width/length-weight relationship, the estimated b values for carapace width-weight in males, females and pooled, were 2.674, 2.719 and 2.783, respectively, and for carapace length-weight they were 2.601, 2.588 and 2.681, respectively. The results show a significant deviation from an isometric growth pattern. An analysis of covariance indicated that there is a significant difference between sexes with respect to the carapace width/length-weight relationship. The relative condition factor values estimated in males and females were 0.9794 ± 0.16 and 1.1280 ± 0.26, respectively, also recording a significant variation (P < 0.01) between sexes. [ABSTRACT FROM AUTHOR]

The deep-water rose shrimp, Parapenaeus longirostris (H. Lucas, 1846), is the most dominant shrimp species on the Algerian west coast. In that area, the diet of P. longirostris was studied between July 2020 and June 2021. This approach to the diet of the rose shrimp was based on analysis of the stomach contents and determination of the ingested prey. A seasonal sampling was carried out in the main fishing ports (Béni Saf, Bouzedjar, Oran and Mostaganem). The results obtained showed that the shrimp feed intensively in spring and increasingly less in winter and summer. Crustaceans, foraminiferans, polychaetes, and molluscs constituted the most frequent preys in the diet, with respective frequencies of 58.85, 55.95, 36.63 and 32.04%. Small microplancton and mesoplancton prey (radiolarians, copepods, and various larvae) were less important in the diet of P. longirostris. Fish and echinoderms constitute accidental prey, of which the frequency is less than 10%. Résumé: La crevette rose profonde, Parapenaeus longirostris (H. Lucas, 1846), est l'espèce de crevette dominante sur la côte algérienne occidentale. Son régime alimentaire a été étudié, dans cette zone, pour une meilleure compréhension de sa stratégie alimentaire. Cette approche est fondée sur l'analyse des contenus stomacaux et la détermination des proies ingérées. Un échantillonnage saisonnier, entre juillet 2020 et juin 2021, a été effectué dans les principaux ports de pêche de l'Ouest algérien (Béni Saf, Bouzedjar, Oran et Mostaganem). Les résultats obtenus ont montré que les crevettes se nourrissent intensivement au printemps et beaucoup moins en hiver et en été. Crustacés, Foraminifères, Polychètes, et Mollusques constituent les proies les plus fréquentes, avec des fréquences respectives de 58,85%, 55,95%, 36,63% et 32,04%. Les petites proies du microplancton et du mésoplancton (Radiolaires, Copépodes et diverses larves) sont moins importantes dans le régime alimentaire de P. longirostris. Les Poissons et les Echinodermes constituent des proies accidentelles, dont la fréquence est inférieure à 10%. [ABSTRACT FROM AUTHOR]

The sex determination and differentiation process of economically important crustaceans have been regarded as the focus of aquaculture for a long time, because of the sex-related weight differences. Neocaridina denticulata sinensis makes a suitable animal model for studying crustaceans because it can reproduce many times under artificial control and has a short reproductive cycle. Male and female sex characteristics of the adult rice shrimp Neocaridina d. sinensis are morphologically obvious, but not in embryos and juvenile stages. At present, sex-specific DNA markers have not yet been developed. To produce a reliable molecular marker for sex in Neocaridina and to investigate molecular sex differentiation, we therefore focused on identifying sex-specific transcriptomic differences. In this study, we found three sex-specific expression genes, NDM , Sushi , and NDF , after screening a large number of transcriptome data. NDM and Sushi are male-specific expression genes, and NDF is a female-specific expression gene. Semi-quantitative RT-PCR analysis showed that NDM and NDF can act as molecular markers for the sex identification of Neocaridina in different developmental stages, especially sex identification for embryos and juveniles with the same morphological characteristics. However, Sushi can only act as a molecular marker for the sex identification of Neocaridina in adult stages. Furthermore, in situ hybridization showed that a strong positive signal of NDM was detected in the male testis. At the same time, we explored the relationship between these three genes and sex differentiation. The results of RNA interference treatment show that knockdown of nd-IAG (Neocaridina denticulata sinensis insulin-like androgenic gland hormone) can change the expression of NDM and NDF. On the basis of the expression of the male-specific gene NDM and the female-specific gene NDF , we developed a molecular test that for the first time allows the unambiguous sex determination of Neocaridina samples lacking external sex-specific features from juvenile stages onward. Résumé: A cause des différences de poids en fonction du sexe, la détermination du sexe et ses mécanismes de différenciation chez les crustacés économiquement importants ont été pendant longtemps au centre de l'attention en aquaculture. Neocaridina denticulata sinensis est un bon modèle pour étudier les crustacés car elle peut se reproduire plusieurs fois sous contrôle artificiel et a un cycle reproducteur court. Les caractéristiques sexuelles mâle et femelle de la crevette adulte Neocaridina d. sinensis sont morphologiquement évidentes, mais pas chez les embryons ou les stades juvéniles. De nos jours, des marqueurs AND spécifiques du sexe n'ont pas encore été développés. Afin de produire un marqueur moléculaire fiable pour le sexe chez Neocaridina et pour explorer la différenciation moléculaire du sexe, nous nous sommes concentrés sur l'identification des différences transcriptomiques spécifiques du sexe. Dans cette étude, après un grand nombre de criblage des données du transcriptome, nous avons trouvé trois gènes d'expression spécifique du sexe, NDM , Sushi , et NDF. NDM et Sushi sont des gènes d'expression spécifiques mâles, et NDF est spécifique femelle. Des analyses par RT-PCR semi-quantitative ont montré que NDM et NDF peuvent servir comme marqueurs moléculaires pour l'identification du sexe de Neocaridina chez différents stades de développement, pour des embryons et des juvéniles avec les mêmes caractéristiques morphologiques. Cependant, Sushi peut seulement server comme marqueur moléculaire pour l'identification du sexe de Neocaridina chez les adultes. De plus, l'hybridation in situ a montré qu'un signal positif fort pour NDM était détecté dans le testicule mâle. En même temps, nous avons exploré l'interrelation entre ces trois gènes et la différenciation sexuelle. Les résultats du traitement de l'interférence par ARN montrent que l'extinction de nd-IAG (hormone de Neocaridina denticulata sinensis semblable à l'insuline de la glande androgène) peut modifier l'expression de NDM et NDF. Sur la base de l'expression du gène spécifique mâle NDM et du gène spécifique femelle NDF , nous avons développé un test moléculaire qui, pour la première fois, permet une détermination du sexe sans ambiguïté sur des échantillons de Neocaridina sans caractère sexuel externe à partir des stades juvéniles. [ABSTRACT FROM AUTHOR]

Based on material collected during the mid- to late 1980s new distributional records for the anchialine shrimp, Caridina rubella Fujino & Shokita, 1975 are presented. Asides from the Ryukyus, Palawan and Sulawesi, the species is now also recorded from Tahiti, Niue, Tonga, Western Samoa, the Loyalty Islands, Solomon Islands, Bohol and Panglao. Attention is drawn to the considerable rostral variation in the species. Résumé: De nouvelles données sur la distribution de la crevette anchialine, Caridina rubella Fujino & Shokita, 1975, établies à partir d'un matériel collecté entre le milieu et la fin des années 1980, sont présentées. Hormis les îles Ryukyu, le Palawan et le Sulawesi, l'espèce est maintenant également signalée à Tahiti, Niue, Tonga, les Samoa occidentales, les îles Loyauté, les îles Salomon, Bohol et Panglao. Les variations rostrales considérables de l'espèce sont soulignées. [ABSTRACT FROM AUTHOR]

The present study represents the first information on direct age determination based on band counts in the mesocardiac ossicle (gastric mill) and eyestalk, in Aristeus alcocki , Penaeus monodon , Penaeus indicus , Panulirus homarus , and Portunus sanguinolentus from India. The determination of growth bands is important in understanding the accurate age of a specimen for the effective management strategies for stock sustainability of the natural resource. Longitudinal sections of the eyestalk and meso-cardiac ossicle of the gastric mill were observed for growth band counts in all species except for P. homarus , where the growth bands were recorded only in the ossicle. Growth bands count five in females and four in males of A. alcocki , respectively. In the case of inshore prawns, two growth bands were observed in P. monodon and one growth band in P. indicus , five growth bands in P. homarus , and three in P. sanguinolentus. Résumé: Cette étude présente la première information sur la détermination directe de l'âge basée sur le nombre des stries de l'osselet méso-cardiaque (moulin gastrique) et des pédoncules oculaires, chez Aristeus alcocki , Penaeus monodon , Penaeus indicus , Panulirus homarus , et Portunus sanguinolentus d'Inde. La détermination des stries de croissance est importante dans la compréhension de l'âge réel pour des stratégies efficaces de gestion en vue du maintien du stock des ressources naturelles. Des sections longitudinales des pédoncules oculaires et de l'osselet méso-cardiaque du moulin gastrique ont été observées pour le comptage des stries de croissance chez toutes les espèces sauf pour P. homarus , où les stries de croissance ont été examinées seulement dans l'osselet. Il a été compté respectivement, cinq stries de croissance chez les femelles et quatre chez les mâles de A. alcocki. Dans le cas des crevettes côtières, deux stries ont été observées chez P. monodon et une chez P. indicus , cinq stries chez P. homarus , et trois chez P. sanguinolentus. [ABSTRACT FROM AUTHOR]

In Mexico, shrimp catch is the main fishing activity, and the second important species is the blue shrimp, Penaeus stylirostris. Specimens of P. stylirostris collected in 2016-2018 from inland waters (bay) and offshore (littoral) in the Santa María la Reforma lagoon (SMLR) system were analysed. The sexes were separated, and then individuals were measured in total length (L , mm) and weighed (W , g). The data were transformed into a natural logarithm and were adjusted to seven candidate models with a multi-model approach (Linear, Quadratic, Cubic, Broken stick, Two segments, Three segments and Four segments: the last two proposed in this study as new equations). A total of 30 439 specimens were analysed. Statistical differences were found in L between areas (KS test, p < 0.0001). Positive and negative allometry was observed according to biometric relationship and sex. The best model was selected with the lowest value of the Akaike information criterion, resulting in the choice of the Four segments model. Resumen: En México la captura de camarón es la principal actividad pesquera y la segunda especie en importancia es el camarón azul Penaeus stylirostris. Se analizaron especímenes de P. stylirostris en aguas interiores (bahía) y exteriores (ribera) del sistema lagunar Santa María la Reforma de 2016 a 2018. A los organismos se les determinó la longitud total (L) en mm y su peso (P) en g. Los sexos se diferenciaron por dimorfismo sexual. Los datos fueron transformados a logaritmo natural y fueron ajustados a siete modelos candidatos con un enfoque múlti-modelo (Lineal, Cuadrático, Cúbico, Línea Rota, Dos segmentos, Tres segmentos y Cuatro segmentos). En total se analizaron 30 439 organismos. Se encontraron diferencias estadísticas en L entre las zonas de captura (prueba KS, p < 0.0001). Se observó una alometría positiva y negativa de acuerdo con la relación biométrica y sexo. El mejor modelo se seleccionó con el menor valor del criterio de información de Akaike, resultando ser el de Cuatro segmentos. [ABSTRACT FROM AUTHOR]

This study dealt with three species of ornamental palaemonid freshwater prawns of the genus Macrobrachium , based on morphological and molecular analysis. Macrobrachium pentazona He, Gao & Guo, 2009; M. laevis Zheng, Chen & Guo, 2019; and M. bilineare sp. nov. are distinguishable from closely related species by segmental ratios, spination of the second pereiopods and the slender scaphocerite. Macrobrachium bilineare sp. nov. can easily be recognized in the field by its bright colour pattern. Molecular evidence of mitochondrial cytochrome oxidase subunit I (COI), also supports the characterization of this new species, raising the total number of Macrobrachium spp. known from China to 41. Detailed description, illustrations, colour photographs, habitat information, distribution maps and features of conservation significance are also briefly discussed. Résumé: Cette étude examine trois espèces de crevettes d'eau douce palémonidées ornementales, sur la base d'analyses morphologiques et moléculaires. Macrobrachium pentazona He, Gao & Guo, 2009 ; M. laevis Zheng, Chen & Guo, 2019 ; et M. bilineare sp. nov. sont différentiables des espèces proches par des ratios segmentaires, les épines des deuxièmes péréiopodes et le mince scaphocérite. Macrobrachium bilineare sp. nov. peut facilement être reconnue sur le terrain par sa couleur vive. Des évidences moléculaires de la sous unité I (COI) de la cytochrome oxydase mitochondriale, appuient aussi la caractérisation de cette nouvelle espèce, portant le nombre total d'espèces de Macrobrachium connues en Chine à 41. Une description détaillée, des illustrations, des photographies en couleur, des informations sur son habitat, des cartes de distribution et des caractéristiques importantes pour la conservation sont discutées. [ABSTRACT FROM AUTHOR]

White shrimps, Litopenaeus setiferus (Linnaeus, 1767) and pink shrimps, Farfantepenaeus duorarum (Burkenroad, 1939) are two pivotal species in the southern Gulf of Mexico, due to their ecological and economic importance. In this study we present observational evidence of the seasonal and interannual variability of both species in the Términos Lagoon (southern Gulf of Mexico). The results suggest that the hydrography of the water column and the surface circulation exert a strong influence on the density of both species. The results presented here contribute to a better understanding of the dynamics of both species and highlight the need to combine different methodologies to achieve a better interpretation of this system. Resumen: El camarón blanco, Litopenaeus setiferus (Linnaeus, 1767) y el camarón rosado, Farfantepenaeus duorarum (Burkenroad, 1939) son dos especies fundamentales en el sur del Golfo de México, debido a su importancia ecológica y económica. En este estudio presentamos evidencia observacional de la variabilidad estacional e interanual de ambas especies en la Laguna de Términos (sur del Golfo de México), mostrando que la hidrografía de la columna de agua y el patron de circulación superficial ejercen una fuerte influencia en la densidad de ambas especies. Los resultados aquí presentados contribuyen a una mejor comprensión de la dinámica de ambas especies y resaltan la necesidad de combinar diferentes metodologías para lograr una mejor interpretación del sistema. [ABSTRACT FROM AUTHOR]

The present analysis can only be considered as preliminary in scope, given the methodology employed and the low number of species analysed, i.e., 10 species of Palaemonidae out of a currently total known biodiversity of more than 400 symbiotic species, as well as more than 50 free-living coral reef-associated species. The species-rich shrimp family Palaemonidae is well known for the majority of species forming a symbiotic relationship with a large variety of invertebrate hosts, such as cnidarians, sponges, molluscs, echinoderms and ascidians (Horká et al., 2016). We use ten randomly selected species of Palaemonidae from a general survey, including representatives of the four main host taxa of Palaemonidae, as well as two free-living species. [Extracted from the article]

In this study, four species of atyid shrimps of the genus Caridina , viz., Caridina cantonensis Yü, 1938, C. breviata N. K. Ng & Cai, 2000, C. gracilipes De Man, 1892 and C. macauensis sp. nov., are documented from Macau, China for the first time. The new species, C. macauensis sp. nov., is identified using morphological and molecular data. According to its morphology, C. macauensis is distinguished from the closely related species C. trifasciata Yam & Cai, 2003, by a shorter rostrum, male second pereiopod and colouration. A diagnosis of the three known species and a full description of C. macauensis sp. nov. are presented. Furthermore, genetic data of C. macauensis sp. nov. derived from the mitochondrial cytochrome c oxidase subunit I (COI) support that this species has a sufficient interspecific divergence from its congeners. Résumé: Dans cette étude, quatre espèces de crevettes Atyidae du genre Caridina , viz., Caridina cantonensis Yü, 1938, C. breviata N. K. Ng & Cai, 2000, C. gracilipes De Man, 1892 et C. macauensis sp. nov., sont rapportées pour la première fois de Macau, Chine. La nouvelle espèce, C. macauensis sp. nov., a été identifiée à l'aide de données morphologiques et moléculaires. Concernant sa morphologie, C. macauensis se distingue de l'espèce la plus proche, C. trifasciata Yam & Cai, 2003, par un rostre plus court, par le second péréiopode mâle et la coloration. Une diagnose des trois espèces connues ainsi qu'une description complète de C. macauensis sp. nov. sont fournies. Par ailleurs, des données génétiques de C. macauensis sp. provenant de l'étude de la sous-unité I de la cytochrome oxydase C mitochondriale (COI) confirment que cette espèce présente une divergence interspécifique suffisante par rapport à ses congénères. [ABSTRACT FROM AUTHOR]

Whether studying a diverse shrimp fauna or close to a major shrimp fishery, this book is the one and only comprehensive reference. Shrimp fisheries and aquaculture have their own chapters, describing the methods and discussing the pros and cons of each. In his Preface to this lengthy work, Raymond Bauer envisions this as a "go-to" book on shrimp. [Extracted from the article]

Female cleaner shrimps Lysmata amboinensis either underwent eyestalk ablations (EA), or were treated with two different wavelength intensities of red light (peak at 630 nm), and then their sex maturation and the effects on their egg quality parameters were compared. Vitellogenesis-inhibiting hormone (VIH), vitellogenin (VTG), VTG-receptor (VTG-R), and crustacean hyperglycemic hormone (CHH) expressions in the hepatopancreas were analysed. VTG-R expression (in situ) levels that caused the EA and red irradiation to induce the synthesis of VTG-R were assessed, and the triglycerides (TG) and glucose levels in the eggs were analysed. VIH expression was decreased in all experimental groups, but VTG and VTG-R expressions were increased. CHH expression and TG and glucose concentrations were higher in the red irradiation group, compared to the EA group. These results confirmed that the red light not only had a positive effect on the promotion of sex maturation, but it also improved the quality of the eggs, when compared to the EA method. Résumé: Les crevettes femelles de Lysmata amboinensis ont, soit subi une ablation des pédoncules (EA), soit été traitées avec deux différentes intensités de longueur d'onde dans le rouge (pic à 630 nm), ensuite leur maturation sexuelle et les paramètres de la qualité des œufs ont été comparés. Les expressions dans l'hépatopancréas de l'hormone inhibitrice de la vitellogénèse (VIH), de la vitellogénine (VTG), du récepteur VTG (VTG-R), et de l'hormone hyperglycémiante des crustacés (CHH) ont été analysées. Les niveaux d'expression de VTG-R (in situ) après EA et l'irradiation rouge pour induire la synthèse de VTG-R ont été évalués, et les concentrations de triglycérides (TG) et de glucose dans les œufs ont été analysées. L'expression de VIH a décru dans tous les groupes expérimentaux, mais les expressions de VTG et VTG-R ont augmenté. L'expression de la CHH et les concentrations de TG et de glucose ont été plus élevées dans le groupe irradié en rouge, par rapport au groupe EA. Ces résultats ont confirmé que la lumière rouge, par rapport à la méthode EA, n'a pas seulement un effet sur la promotion de la maturation sexuelle, mais améliore aussi la qualité des œufs. [ABSTRACT FROM AUTHOR]

The spot prawn fishery, targeting Pandalus platyceros , has failed to prove commercially viable on the Mexican Pacific coast. A survey was carried out off the northwestern coast of Baja California, at depths of 140-180 m. The objective was to describe the biological traits of the species to test the hypothesis that warmer water stimulates higher growth parameters. An average model was estimated that anticipated an inverted exponential growth curve, consequently the growth parameters of the Von Bertalanffy model were obtained as k = 0.421 , L ∞ = 47.44 mm carapace length (CL) and t 0 = 0. Being a protandric hermaphrodite, the transition size was estimated at 40.8 mm CL. The results challenged the hypothesis that P. platyceros grows faster in temperate environments than in cold environments. Resumen: La pesquería del langostino mancha blanca Pandalus platyceros no ha logrado consolidarse como pesca comercial en la costa del Pacífico mexicano. Se realizó una prospección frente a la costa noroeste de Baja California, su límite de distribución más sureño, a profundidades de 140-180 m. El objetivo fue describir los rasgos biológicos de la especie para probar la hipótesis de que las aguas más cálidas favorecen los parámetros de crecimiento. Se estimó un modelo promedio que presentó una curva exponencial invertida por lo que se ajustaron los parámetros del modelo de crecimiento de Von Bertalanffy con k = 0.421 , L ∞ = 47.44 mm longitud de caparazón (LC) y t 0 = 0. Siendo un hermafrodita protándrico se estimó la talla de transición en 40.8 mm LC. Estos resultados retan la hipótesis de que P. platyceros presenta más rápido crecimiento en ambientes templados en comparación con ambientes fríos. [ABSTRACT FROM AUTHOR]

We investigated the presence and ecology of Chirocephalus croaticus (Steuer, 1899) during three successive seasons (spring and autumn 2018, spring 2019) at Lake Petelinje (SW Slovenia). Although the presence (duration, abundance) of this fairy shrimp strongly differs among different seasons and both years, we showed that in a season with favourable conditions (spring 2018) its abundance increases rapidly at the end of the season as the shrimps persist in small pools until the water dries out. The species may appear again during the autumn, however, its abundance and persistence seem to be much lower and shorter than during the spring, respectively. Nevertheless, persistence and abundance may also differ strongly among the two successive spring seasons (less shrimps found during the shorter season of 2019 than in 2018). Larvae appear first, and are most abundant at the beginning of the season, and are followed by adult males (protandry) and females, which become most abundant at the end of the season. Also, larvae seem to be more abundant on exposed bottom (gravel path), while adults are much more abundant in the shelter of a submerged meadow. Ovigerous females had 9-37 cysts (fertilized eggs) in their brood pouch, and the position of differently developed eggs changed during the season; the presence of females without eggs during mid- and at the end of season indicates the production of thin-shelled summer, and thick-shelled winter cysts, respectively. In contrast with the water decrease that is in strongly negative association with the abundance of the fairy shrimps (lake size — abundance: r = − 0.56 , P < 0.001), no other environmental parameters were highly associated (r ⩽ | 0.38 |) with species abundance. Although the local population (one of only two currently known) seems to be in good condition, appropriate conservation action should be taken to prevent the decrease of this population in the future. Résumé: Nous avons étudié la présence et l'écologie de Chirocephalus croaticus (Steuer, 1899) au cours de trois saisons successives (printemps et automne 2018, printemps 2019) dans le Lac Petelinje (SO Slovanie). Bien que la présence (durée, abondance) de cette crevette diffère fortement selon les différentes saisons et les deux années, nous avons montré que dans une saison avec des conditions favorables (printemps 2018) son abondance augmente rapidement à la fin de la saison et que les crevettes persistent dans des flaques d'eau jusqu'à l'assèchement. L'espèce peut apparaitre de nouveau en automne, cependant son abondance semble être plus basse et sa persistance plus courte que pendant le printemps. Néanmoins, persistance et abondance peuvent aussi différer entre deux printemps successifs (moins de crevettes trouvées durant la courte saison de 2019 qu'en 2018). Les larves apparaissent en premier et sont plus abondantes en début de saison, elles sont suivies par des males adultes (protandrie) et les femelles qui deviennent plus abondantes en fin de saison. De plus, les larves semblent être plus abondantes sur des fonds ouverts (graviers), tandis que les adultes sont beaucoup plus abondants dans les abris de prairies submergées. Les femelles ovigères avaient 9-37 cystes (œufs fécondés) dans leur poche incubatrice, et la position des œufs à des stades de développement différents change au cours de la saison ; la présence des femelles sans œufs à la mi-saison et en fin de saison indique la production de cystes d'été à fine enveloppe et de cystes d'hiver à enveloppe épaisse. Alors que la baisse de l'eau est fortement associé négativement avec l'abondance des crevettes (taille du lac — abondance : r = − 0 , 56 , P < 0 , 001), aucun autre facteur environnemental n'a été aussi fortement associé (r ⩽ | 0 , 38 |) avec l'abondance de l'espèce. Bien que la population locale (une ou deux connues actuellement) semble être en bonne condition, une action de conservation appropriée devrait être prise pour éviter la diminution de cette population dans le futur. [ABSTRACT FROM AUTHOR]

Currently, I A. ochotensis i is divided into two subspecies: I A. o. ochotensis i Komai, 1997 (southern part of the Sea of Okhotsk at depths of over 600 m) and I A. o. kamtschatica i Sokolov, 2001 (northern part along the Kamchatka Peninsula at shallower depths of 150-259 m) (Sedova & Grigoriev, 2018). The crangonid shrimp I Argis toyamaensis i (Yokoya, 1933) is a typical, representative deep-sea species in the Sea of Japan and found at depths of 250-2000 m (Komai, 1997). [Extracted from the article]

The large size variation of Macrobrachium amazonicum reflects a complex population structure that consists of four morphotypes, called TC (Translucent Claw), CC (Cinnamon Claw), GC1 (Green Claw 1), and GC2 (Green Claw 2). The effect of the largest morphotype (GC2) claws on development and behaviour of the smallest male morphotype (TC) was analysed through manipulations of the large prawn's second pair of claws. TC males were paired for 75 days in aquaria with (a) an intact GC2, (b) a GC2 with immobilized dactyls, and (c) a GC2 without chelipeds. Isolated TC males served as a control. The maintenance activities of TC males and social interactions with the GC2 morphotype were monitored. Survival and growth of TC males was lower in relation to the control when they were paired with intact GC2 males. Aggressive interactions were carried out almost exclusively by GC2 and strongly affected the behaviour of the small prawns. The absence of chelipeds and immobilization of dactyls in GC2 prawns reduced the negative effect on the development of TC males and agonistic behaviour. The social interactions between GC2 and TC prawns reflect a stable dominance hierarchy. The large claw of the GC2 morphotype plays a major role in the social interaction. Resumo: A grande variação de tamanho de Macrobrachium amazonicum reflete uma estrutura populacional complexa que consiste em quatro morfotipos, chamados TC (Translucent Claw), CC (Cinnamon Claw), GC1 (Green Claw 1) e GC2 (Green Claw 2). O efeito dos quelípodos maiores do morfotipo (GC2) no desenvolvimento e comportamento do menor morfotipo masculino (TC) foi analisado através de manipulações do segundo par de quelípodos do camarão grande. Os machos TC foram pareados por 75 dias em aquários com (a) um GC2 intacto, (b) um GC2 com dactilos imobilizados e (c) um GC2 sem quelípodos. Machos TC isolados serviram como controle. As atividades de manutenção do macho TC e interações sociais com o morfotipo GC2 foram monitoradas. Sobrevivência e crescimento do macho TC foram mais baixos em relação ao controle quando eles estavam pareados com os machos GC2 intactos. As interações agressivas foram realizadas quase exclusivamente pelo GC2 e afetaram fortemente o comportamento dos camarões pequenos. A ausência dos quelípodos e imobilização de dáctilos em camarões GC2 reduziram o efeito negativo no desenvolvimento de machos TC e o comportamento agressivo do camarão dominante. As interações sociais entre os camarões GC2 e TC refletem uma hierarquia de dominância estável. O quelípodo grande do morfotipo GC2 desempenha um papel importante na interação social. [ABSTRACT FROM AUTHOR]

The insulin signalling pathway is one of the most studied pathways, including ovary maturation and female reproduction. However, downstream elements involved in this cascade remain unknown. Here, we identified and characterized an insulin-like receptor (IR) in female Macrobrachium rosenbergii , and named as Mro-IR. The deduced Mro-IR contained conserved domains of IR proteins, including two ligand-binding domains, a furin-like domain, two fibronectin-3 domains, a transmembrane domain and an intracellular tyrosine kinase domain in order. Multiple sequence alignment of the first ligand-binding domain and the tyrosine kinase domain in Mro-IR revealed a high degree of similarity to other representative IRs. Mro-IR was clustered into a separate branch with IRs from decapods by phylogenetic analysis. Additionally, tissue distribution analysis showed that Mro-IR was uniquely expressed in the ovary of M. rosenbergii. This study would possibly provide a new highlight to the molecular mechanism of insulin-like signalling cascade, regulating female sexual differentiation in crustaceans. Résumé: La voie de signalisation de l'insuline est l'une des voies la plus étudiée, y compris pour la maturation ovarienne et la reproduction femelle. Cependant des éléments impliqués en aval dans cette cascade restent inconnus. Nous avons identifié et caractérisé un récepteur de type insuline (IR) chez les femelles de Macrobrachium rosenbergii , et l'avons nommé Mro-IR. Ce Mro-IR contient des domaines conservés de protéines IR, incluant deux domaines de liaison au ligand, un domaine semblable à la furine, deux domaines fibronectine-3, un domaine transmembranaire et un domaine tyrosine kinase intracellulaire. Les alignements de séquences multiples du premier domaine de liaison au ligand et du domaine tyrosine kinase de Mro-IR ont révélé un grand degré de similarité avec d'autres IR. Par des analyses phylogénétiques, Mro-IR a été regroupé dans une branche séparée avec les IR des décapodes. De plus l'analyse de distribution dans les tissus a montré que Mro-IR a été exprimé uniquement dans les ovaires de M. rosenbergii. Cette étude pourrait fournir un nouvel éclairage sur le mécanisme moléculaire de la cascade de signalisation de l'insuline, régulant la différenciation sexuelle femelle chez les crustacés. [ABSTRACT FROM AUTHOR]

Prawns of the species Exopalaemon carinicauda were fed with Artemia that had been enriched by either 1, or 3, or 5 g/l DHA powder. The feeding dose of Artemia offered to E. carinicauda was calculated according to the water volume, and maintained at 1-3 individuals/ml. After nutritional enrichment, the ratio of DHA content to total fatty acid content in Artemia was the highest (3.32%) after being fed 3 g/l DHA powder. The ratio of DHA content to total fatty acid content in the muscle tissue of E. carinicauda prawns fed with Artemia enhanced with 3 g/l DHA powder was also the highest (4.40%) achieved. Furthermore, when the concentration of fish oil DHA powder was 3 g/l, the survival rate of the prawns was significantly higher than in the control group, with the specific growth rate and weight gain reaching 11.39%/day, and 95.74%, respectively. In addition, the DHA-enhanced Artemia , at different concentrations, increased the non-specific immunity of individuals. The enzyme activity of T-AOC, SOD and AKP in the respective feeding groups of prawns was significantly higher, compared to the control group. Thus, Artemia enriched by 3 g/l DHA powder is proposed as an optimal choice for the offspring breeding of E. carinicauda. Résumé: Des crevettes de l'espèce Exopalaemon carinicauda ont été nourries avec des Artemia enrichies avec soit 1 ou 3 ou 5 g/L de poudre de DHA. La dose d'alimentation d' Artemia offerte à E. carinicauda a été calculée en fonction du volume d'eau et maintenue à 1-3 individus/ml. Après enrichissement nutritionnel le ratio de la teneur en DHA sur la teneur totale en acides gras dans les Artemia a été le plus élevé (3.32%) après avoir été nourries avec 3 g/L de poudre de DHA. Le ratio de la teneur en DHA sur la teneur totale en acides gras dans les muscles de crevettes E. carinicauda nourries avec les Artemia enrichies avec 3 g/L de poudre de DHA a aussi été le plus élevé (4.40%) obtenu. De plus, quand la concentration de poudre de DHA d'huile de poisson a été de 3 g/L la survie des crevettes a été significativement plus élevée que dans le groupe témoin, avec un taux de croissance et un gain de poids atteignant respectivement 11,39%/d, et 95,74%. Enfin, les Artemia enrichies en DHA à différentes concentrations, ont augmenté l'immunité non-spécifique des individus. L'activité enzymatique de T-AOC, SOD et AKP dans les groupes d'alimentation respectifs de crevettes a été significativement plus élevée que chez le groupe témoin. Ainsi les Artemi a enrichie avec 3 g/L de poudre de DHA sont proposées comme un choix optimal pour l'élevage de la progéniture de E. carinicauda. [ABSTRACT FROM AUTHOR]

The caridean shrimp Palaemon argentinus is a species of commercial and ecological interest. Its numerous larval stages, the lack of knowledge on their nutritional requirements, and their ability to survive in a wide range of salinities raise questions on the optimum conditions for larval rearing in captivity. The present study was aimed at evaluating embryonic development under different salinities and larval development under different combinations of salinities and diet regimes, in order to define alternative, cheaper culture conditions. We tested salinities usually encountered by the species in natural habitats (0.1, 1 and 5 ppt) and a highly protein-inert diet (Tetracolor®) as a potential replacement for live food (nauplii of Artemia salina). The incubation period and fecundity were similar among salinity treatments. Overall, the number of survival days and percentage of zoeae that moulted two, three and four times were higher when embryogenesis occurred at 5 ppt and when larvae were exposed to 5 ppt. These results suggest that the conditions experienced by embryos affect the performance of the first larval stages, and probably reflect the lower energetic requirements of zoeae to osmoregulate as water and haemolymph osmolarity become closer. On the other hand, larval performance was better when fed A. salina nauplii than Tetracolor®. The latter may not cover the nutritional requirements of zoeae or may have low digestibility due to insufficient enzymes in the undeveloped larval digestive system. Based on the present results, we conclude that a salinity of 5 ppt combined with a diet consisting of Artemia sp. nauplii is optimal for larval culture at early stages. Resumen: El camarón carideo Palaemon argentinus es una especie de interés económico y ecológico. Sus numerosos estadios larvales, cuyos requerimientos nutricionales se desconocen, y la capacidad de las larvas de sobrevivir bajo un amplio rango de salinidades plantean interrogantes sobre las condiciones óptimas para el cultivo larval en cautiverio. El objetivo del presente trabajo fue evaluar el desarrollo embrionario bajo diferentes salinidades y el desarrollo larval bajo distintas combinaciones de salinidades y dietas, para definir condiciones de cultivo alternativas de menor costo. Seleccionamos para ello salinidades a las que la especie está frecuentemente expuesta en su ambiente natural (0,1, 1 y 5 ppt) y una dieta altamente proteica (Tetracolor®) como potencial reemplazo del alimento vivo (larvas nauplius de Artemia salina). El periodo de incubación y la fecundidad fueron similares en las distintas salinidades ensayadas. Por su parte, el número de días de supervivencia y porcentaje de zoeas que mudaron dos, tres, o cuatro veces fueron mayores cuando la embriogénesis ocurrió a 5 ppt y cuando las larvas fueron expuestas a 5 ppt. Estos resultados sugieren que las condiciones experimentadas por los embriones afectan el desempeño de los primeros estadios larvales, y reflejan probablemente el menor costo energético de osmorregular al acercarse la osmolaridad del agua a la de la hemolinfa. Por otro lado, se observó un mejor desarrollo de las larvas cuando fueron alimentadas con nauplius de A. salina. Es posible que Tetracolor® no cubra los requerimientos nutricionales de las larvas o presente una menor digestibilidad debido a una baja producción de enzimas en el aparato digestivo poco desarrollado de las larvas. De acuerdo a los resultados obtenidos, concluimos que una salinidad de 5 ppt y una dieta basada en alimento vivo es la combinación óptima para el cultivo de los primeros estadios larvales de la especie. [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 family Anchistioididae comprises a single genus Anchistioides with three species: A. compressus and A. willeyi from the tropical Indo-West Pacific, and A. antiguensis from the tropical West Atlantic. The two Indo-West Pacific species are known to be symbionts of sponges. Material collected in recent years throughout the Indo-West Pacific yielded range extensions as well as new host records. This material is herein described and their infraspecific morphological variation discussed. Résumé: La famille Anchistioididae comprend un seul genre Anchistioides et trois espèces : A. compressus et A. willeyi de l'Indo-Ouest Pacifique tropical et A. antiguensis de l'Atlantique Ouest tropical. Les deux espèces indo-occidentales du Pacifique sont connues pour être des symbiotes d'éponges. Le matériel collecté dans les dernières années dans l'Indo-Ouest Pacifique a permis d'élargir leur répartition ainsi que l'observation de nouveaux enregistrements hôtes. Ce matériel est décrit ici et la variation morphologique infraspécifique est discutée. [ABSTRACT FROM AUTHOR]

The atyid shrimps of Caridina nilotica species group from China are reviewed. Taxonomic diagnosis and discussions are given to three species so far known from China, viz. Caridina gracilipes De Man, 1892, Caridina macrophora Kemp, 1918 and Caridina elongapoda Liang & Yan, 1977. Detailed morphological description and illustrations are provided for a new species. Caridina sheni sp. nov. is morphologically similar to C. gracilipes but could be distinguished by its much longer dactylus of third and fifth pereiopods, and lower number of ventral rostral teeth. Résumé: Les crevettes Atyidae du groupe d'espèces Caridina nilotica de Chine sont révisées. La diagnose taxonomique et des discussions sont données pour trois espèces connues jusqu'à présent de Chine, soit Caridina gracilipes De Man, 1892, Caridina macrophora Kemp, 1918 et Caridina elongapoda Liang & Yan, 1977. La description morphologique détaillée et des illustrations sont fournies pour une nouvelle espèce. Caridina sheni sp. nov. est morphologiquement similaire à C. gracilipes mais s'en distingue par son dactyle beaucoup plus long des troisièmes et cinquièmes péréiopodes et un plus petit nombre de dents rostrales ventrales. [ABSTRACT FROM AUTHOR]

A new species of the sergestid shrimp genus Sicyonella Borradaile, 1910 was discovered in a recent expedition to southern Madagascar. The presence of Sicyonella in Madagascar is also a new genus record for the country. The new species has the petasma and thelycum very different from the three known species of the genus, and is also unique in the basal part of the mesial antennular flagellum not being modified in males. Résumé: Une nouvelle espèce du genre de crevettes Sergestidae, Sicyonella Borradaile, 1910 a été découverte lors d'une expédition récente au sud de Madagascar. La présence du genre Sicyonella à Madagascar est aussi un nouveau signalement pour le pays. La nouvelle espèce présente un pétasma et un thélycum très différents de ceux des trois espèces connues du genre, et est aussi unique par la partie basale non modifiée du flagelle antennulaire mésial chez les mâles. [ABSTRACT FROM AUTHOR]

Meat yield is an important indicator of the commercial value of crustaceans. We investigated the correlations between morphometric characteristics and meat yield in Macrobrachium rosenbergii (De Man, 1879), in order to determine which traits were correlated with high meat yield. The association between morphometric characteristics and meat yield were estimated using statistical methods, including correlation coefficients, determination coefficients, path coefficients, and regression equations. In the same "family" [= cultured lineage or strain], the meat yield of males was often slightly lower than that of females. The meat yield of different male morphotypes ranged from 19.90% to 38.12%, while that of different female stages ranged from 30.14% to 35.59%. Among male morphotypes, the "small male" had the largest meat yield, and "old blue claw" had the lowest meat yield (P < 0.05). Among the various female developmental stages, stage I had the largest meat yield, and stage III female had the lowest meat yield (P < 0.05). The multivariate linear regression equation for meat yield of males contained four independent variables, and the determination coefficient was 0.744. The regression equation for females contained five independent variables, and the determination coefficient was 0.456. The characteristics that had the largest direct positive effect for meat yield were abdominal weight/body weight in males (0.862) and body length in females (0.441). These results can provide reference data for selecting M. rosenbergii with high meat yield, in order to improve the economic benefit of the prawn processing industry. Résumé: Le rendement en chair est un indicateur important pour la valeur commerciale des crustacés. Nous avons étudié les corrélations entre les caractéristiques morphométriques et le rendement en chair de Macrobrachium rosenbergii (De Man, 1879), afin de déterminer quels traits étaient corrélés avec un fort rendement en chair. L'association entre les caractéristiques morphologiques et le rendement en chair a été estimée par des méthodes statistiques incluant les coefficients de corrélation, les coefficients de détermination, les coefficients de chemin les équations de régression. Dans la même "famille" (lignée ou souche), le rendement en chair des mâles a souvent été significativement plus bas que celui des femelles. Le rendement en chair des différents morphotypes mâles varie de 19,90% à 38,12%, tandis que celui des différents stades de femelles varie de 30,14% à 35,59%. Parmi les morphotypes de mâles, le "petit mâle" a le rendement de chair le plus élevé, et le "vieux à pince bleue" a le plus faible (P < 0.05). Parmi les différents stades de développement des femelles, le stade I a le rendement de chair le plus élevé et le stade III a le plus faible (P < 0.05). L'équation de régression linéaire multivariée pour le contenu en chair des mâles contient quatre variables indépendantes, et le coefficient de détermination est de 0,744. L'équation de régression pour les femelles contient cinq variables indépendantes, et le coefficient de détermination est de 0,456. Les caractéristiques qui ont le plus grand effet positif pour le contenu en chair ont été le rapport poids abdominal/ poids du corps chez les mâles (0,862) et longueur du corps chez les femelles (0,441). Ces résultats peuvent fournir des données de référence pour sélectionner des M. rosenbergii avec un rendement en chair élevé afin d'améliorer le bénéfice économique de l'industrie de la transformation des crevettes. [ABSTRACT FROM AUTHOR]

The yellowlegs shrimp Penaeus californiensis is an oceanic species that approaches the coastal zone for its reproduction. However, in the southern Gulf of California, this species also enters coastal lagoons to grow and reproduce. To test the hypothesis that the growth of P. californiensis differs between these two environments, monthly samplings of shrimp were made in the interior of the Navachiste coastal lagoon and its adjacent marine area. To determine growth, age groups were identified using the size structures over time. Five cases of the Schnute model were adjusted to the data, and the best case was selected using a multi-model selection approach. A sigmoid-shaped curve best represented the female data (case 2), and the inverted exponential curve (case 5; equivalent to the Von Bertalanffy growth function) was best for males. Average growth differed between sexes (p = 0.0097) but not between environments (p = 0.559). Resumen: El camarón café, Penaeus californiensis , se considera oceánico que se acerca a la zona litoral para su reproducción. Sin embargo, en el sur del Golfo de California se ha observado que también ingresa a lagunas costeras para crecer y reproducirse. Para probar la hipótesis de que el crecimiento de P. californiensis difiere en estos dos ambientes, se realizaron muestreos mensuales de camarones en la zona litoral y al interior de la Laguna de Navachiste. Para determinar el crecimiento se identificaron grupos de edad en las estructuras de tallas a través del tiempo. Cinco casos del modelo de Schnute se ajustaron a los datos y se seleccionó el mejor usando selección multi-modelo. La curva de forma sigmoidea es la que mejor describió los datos de las hembras (caso 2) y la exponencial invertida (caso 5; equivalente a la función de crecimiento de Von Bertalanffy) fue la mejor para machos. El crecimiento promedio difirió entre sexos (p = 0.0097) pero no entre ambientes (p = 0.559). [ABSTRACT FROM AUTHOR]

The objective of this study was to assess the patterns in the spatial distribution, size structure, morphometric relationships, and relationships of biomass and size to sampling depth and distance to the coast of Penaeus notialis in the Colombian Caribbean. The biological data were collected on board a shrimp trawler. The females were larger and heavier than the males, which indicated distinct sexual dimorphism in body size. The cephalothorax length at 50% maturity in females was 26.49 mm, and in males, it was 15.13 mm. Relatively high biomass values were found in the southern zone of the study area at depths between 25.6 and 49.3 m and between 3.94 and 7.80 nmi (= 7.29-14.45 km) from the coast. We found a clear spatial structure of biomass and size in relation to depth, so that the fishing effort can be directed to the locations of the adult population. Resumen: El objetivo de este estudio fue evaluar los patrones de distribución espacial, estructura de tallas, relaciones morfométricas, y relaciones de la biomasa y tallas con la profundidad y distancia de la costa de Penaeus notialis en el Caribe colombiano. Los datos biológicos fueron tomados a bordo de un barco camaronero arrastrero. Las hembras fueron más grandes y pesadas que los machos, mostrando un distinto dimorfismo sexual en tamaño. La longitud al 50% de madurez del cefalotórax en hembras fue 26.486 mm y en machos 15.134 mm. Valores relativamente altos de biomasa fueron encontrados en la zona sur del área de estudio, en profundidades entre 25.6 y 49.3 m y distancia de la costa de 3.94 a 7.80 nmi (= 7.29-14.45 km). Se encontró una clara estructura especial de la biomasa y las tallas relacionadas con la profundidad, para que el esfuerzo se pueda dirigir donde la población adulta está localizada. [ABSTRACT FROM AUTHOR]

An abnormal bifid rostrum is reported for the first time for a wild-caught subadult female (carapace length = 22.5 mm) of the pink shrimp Farfantepenaeus duorarum (Burkenroad, 1939) from Celestun lagoon, Yucatan, southern Gulf of Mexico. A review of registers on morphological abnormalities in shrimps of the family Penaeidae is provided. Resumen: Se reporta por primera vez un rostro bífido anormal para una hembra subadulta silvestre (longitud del cefalotórax = 22,5 mm) del camarón rosado Farfantepenaeus duorarum (Burkenroad, 1939) de la laguna costera Celestún, Yucatán, sur del golfo de México. Se proporciona una revisión de registros sobre anormalidades morfológicas en camarones de la familia Penaeidae. [ABSTRACT FROM AUTHOR]

Knowledge of the diet of Macrobrachium macrobrachion (Herklots, 1851) in its natural environment is a key factor facilitating its successful breeding. We have analysed the stomach content of 452 specimens collected from the Ouémé River Delta (ORD) (338 stomachs) and from the Mono River/Grand-Popo Lagoon complex (MGLC) (114 stomachs), from February to October 2016. The analysis enables to calculate the coefficient of vacuity for the ORD (3.50%) and for the MGLC (3.50%). The results show that M. macrobrachion has a detritivore-omnivore type of diet, feeding mainly on phytoplankton (diatoms and cyanophytes) and detritus. However, the diet of the young shrimps, composed mostly of insect larvae, differs from that of adult. In the adult M. macrobrachion , the pace of feeding activities is greatest in the morning (6.00 to 9.00 am), low in middle of the day (10.00 am to 13.00 pm), and there is a slight trophic activity between 17.00 and 22.00 pm. Outside of the above periods, i.e., from 14.00 to 16.00 pm and 23.00 pm to 5.00 am, the species is at rest. Juveniles feed at dawn. In the nighttime and at dusk, groups of shrimps of varying sizes do feed. The findings of this study suggest that live prey is the best feed for the larvae of M. macrobrachion in captivity and should be distributed preferably early in the morning. Résumé: La connaissance du régime alimentaire de Macrobrachium macrobrachion (Herklots, 1851) dans son environnement naturel est un facteur clé pour la réussite de son élevage. Nous avons analysé le contenu stomacal de 452 spécimens prélevés dans le delta du fleuve Ouémé (ORD) (338 estomacs) et dans le complexe du fleuve Mono/Lagune de Grand-Popo (MGLC) (114 estomacs), de février à octobre 2016. L'analyse de ces estomacs a permis de calculer le coefficient de vacuité pour l'ORD (3,50%) et pour le MGLC (3,50%). Les résultats montrent que M. macrobrachion a un régime alimentaire de type détritivore-omnivore, se nourrissant principalement de phytoplancton (diatomées et cyanophytes) et de détritus. Cependant, le régime alimentaire des jeunes crevettes, composé principalement de larves d'insectes, diffère de celui des adultes. Chez les adultes de M. macrobrachion , le rythme des activités d'alimentation est plus élevé le matin (6 h à 9 h), faible en milieu de journée (10 h à 13 h), et il y a une légère activité trophique entre 17 h et 22 heures. En dehors des périodes ci-dessus, c'est-à-dire de 14 h à 16 h et de 23 h à 5 h, l'espèce est au repos. Les juvéniles se nourrissent à l'aube. Pendant la nuit et au crépuscule, des groupes de crevettes de différentes tailles se nourrissent. Les résultats de cette étude suggèrent que les proies vivantes sont le meilleur aliment pour les larves de M. macrobrachion en captivité et devraient être distribuées de préférence tôt le matin. [ABSTRACT FROM AUTHOR]

The major biodiversity on the planet is present in coastal and oceanic environments, despite this, on the northern continental shelf of Brazil, data on most of the marine groups still are deficient, especially in areas deeper than 20 m and in the continental slope area. This lack of data is aggravated by high fisheries exploitation, which causes a decline in large, abundant populations, even leading them to threat of extinction. Among that marine biodiversity, no group has a larger morphological variety than crustaceans. In this scenario, knowledge about the local biodiversity, its richness and seasonality, is essential for a qualified fisheries management. The Amazon continental shelf has one of the largest shrimp fisheries in the country, and due to the ecological and economic importance that crustaceans have in the region, a detailed study on their diversity is necessary. In this article, we use data collected in the Revizee Program. We identified 91 species: crabs (32.97%), shrimp (28.57%), anomurans (10.99%), soft crabs (10.99%), lobsters (9.89%), stomatopods (4.40%) and isopods (2.20%). The State of Amapá had fewer species (n = 11) compared to Pará (n = 47). The data analysis shows there is a lack of knowledge about the real biodiversity present on the Amazon continental shelf. [ABSTRACT FROM AUTHOR]

We report on 13 species collected during the 1973 expedition onboard the MY "Velero IV": seven Euphausiidae (krill), two Benthesicymidae shrimp, two Sergestidae shrimp, one Acanthephyridae shrimp, and one Portunidae crab. Four species are new records for Costa Rica: Bentheogennema burkenroadi, Gennadas scutatus, Neosergestes consobrinus, and Phorcosergia filicta. [ABSTRACT FROM AUTHOR]

This study was to examine the immunomodulatory effects of oxytetracycline (OTC) on the white shrimp Litopenaeus vannamei (Boone, 1931). Immune parameters were not suppressed by OTC treatment in haemocytes in vitro. A total of 96 healthy shrimp were divided into four groups. Group 1 was the control group. Group 2 received 50 mg OTC/kg body weight/day. Group 3 received 1 g β -glucan/kg feed. Group 4 received 50 mg OTC/kg body weight/day and 1 g/kg β -glucan. OTC residues were more highly accumulated in the hepatopancreas than in muscle tissue during the rearing period, and the addition of β -glucan prolonged the retention time of OTC in the muscle tissue. Additionally, dietary administration of OTC in combination with β -glucan facilitated the excretion of OTC from the hepatopancreas. Shrimp that orally ingested OTC alone had an elevated total haemocyte count, phagocytosis, superoxide anion production and prophenoloxidase activity, and these immunostimulatory effects were further enhanced in shrimp receiving OTC in combination. [ABSTRACT FROM AUTHOR]

Heat shock proteins play an important role in maintaining normal cell function and overcoming stress conditions in organisms. Expression of the heat shock protein 70 gene (hsp70) at different stages of embryos and larvae of the giant freshwater prawn, Macrobrachium rosenbergii (De Man, 1879) was analysed using quantitative real-time polymerase chain reaction. Expression of hsp70 was first detected in embryos of 5.5 days old; the expression levels gradually increased during the course of embryonic development, reaching their maximum at the stage prior to hatching. Whereas the expression levels were high in newly hatched larvae, they lowered subsequently before increasing to their maximum after 20 days post-hatch. Moreover, induction of hsp70 expression in 5.5 days old embryos and newly hatched larvae by two xenobiotics, 4-nonylphenol (4-NP) and chlorpyrifos (CPF) was also investigated. The results showed that both 4-NP and CPF caused similar patterns of hsp70 expression changes. Embryos exposed to 4-NP or CPF for 24 h increased the hsp70 expression levels with increasing concentrations of 4-NP or CPF. Prolonged exposure for 96 h induced higher levels of responses. The larvae were more sensitive than the embryos to both 4-NP and CPF challenges, by responding to lower concentrations of stressors and producing higher expression levels. The study suggests that hsp70 plays an active role during early life stages of M. rosenbergii , indicating the presence of mechanisms to overcome stress caused by development or by external stressors at these stages. [ABSTRACT FROM AUTHOR]

A new species of telescope shrimp, Ogyrides sindibadi sp. nov. is described from Kuwait. The new species is morphologically similar to O. striaticauda Kemp, 1915, originally described from Chilka Lake (India), but can be distinguished by the shape of the scaphocerite, the much longer dactylus of the third pereiopod, as well as the shape of the distal margin of the telson. [ABSTRACT FROM AUTHOR]

In tropical countries, a large number of finfish species and invertebrates are captured as by-catch, including several species of crustaceans, due to the low selectivity of the fishing methods. By-catch presents and optimal opportunity to study populations of crustaceans. Here, the goal was to determine the community structure, specifically through the size structure, as well as the average sizes at first maturity of crustacean species present in the shrimp by-catch caught aboard a fishing vessel operating in the Mexican Pacific, from Sinaloa to Guerrero, Mexico. From the 18 crustaceans found in this study, the crabs Euphylax robustus and Achelous asper were the dominant species, whereas four species were considered casual (i.e., not frequent). Interestingly, more than 40% of the organisms analysed were in the juvenile stage, and 19% were ovigerous females. The results demonstrate the negative impact of the low selectivity of shrimp trawls on the communities of species of Crustacea. [ABSTRACT FROM AUTHOR]

Length-weight relationship (LWR) was estimated for three stomatopod species, namely Oratosquillina perpensa (Kemp, 1911), Harpiosquilla raphidea (Fabricius, 1798) and Miyakella nepa (Latreille, 1828) for the first time from the north-eastern Arabian Sea. Experimental fishing, using a shrimp trawl, was conducted fortnightly during September 2017 up to April 2018 along the Maharashtra coast. A total of 821 samples were collected. Length-weight relationship showed good fit with coefficient of determination ( r 2 ) values varying from 0.9190 to 0.9612. In this study, b values ranged from 2.758 to 3.140. The LWRs of Oratosquillina perpensa and Miyakella nepa have not yet been reported in the SealifeBase. [ABSTRACT FROM AUTHOR]

Active promoters are urgently needed for shrimp cells which are hard to be immortalized. Translationally controlled tumor protein (TCTP) is a widely and abundantly expressed, growth-related protein. In this study we successfully isolated the promoter (Ptctp) and ORF (= open reading frame) of the TCTP gene from Litopenaeus vannamei and analysed the promoter activity of Ptctp and the growth-promoting effects of over-expressed TCTP protein in the primary Oka organ (lymphoid tissue) cells. It was found, that cytomegavirus (CMV) promoter, highly active in mammalian and fish cells, had a driving activity too low to be detected in shrimp cells. However, shrimp Ptctp had a higher driving activity than Pcmv in the shrimp cells and an obvious fluorescent signal was observed in the shrimp cells transfected by a Pcmv-Ptctp-driven plasmid. However, no obvious growth-promoting effects were observed in the eGFP/TCTP [eGFP = enhanced green fluorescent protein] or TCTP-transfected shrimp cells possibly due to the relatively low expression efficiency. [ABSTRACT FROM AUTHOR]

The species composition of the Decapoda suborder Dendrobranchiata in waters around and off the Canary Islands has received increasing attention in recent years (Landeira & Fransen, 2012; González & Santana, 2014; Landeira & González, 2018). Shrimps were caught as by-catch of the local artisanal fishery of the striped soldier shrimp I Plesionika edwardsii i (Brandt, 1871) with multiple semi-floating shrimp traps (Arrasate-López et al., 2012; Pajuelo et al., 2018). The checklist of the dendrobranchiate shrimps from the Canary Islands has been recently published by Landeira & González (2018), where a total of 49 species were listed. [Extracted from the article]

For the purpose of studying the epigenetic characteristics of the mitochondrial genome of the ridgetail white prawn, Exopalaemon carinicauda (Holthuis, 1950) under Cd2+ and Cr6+ heavy metal stress, the mitochondrial DNA methylation of E. carinicauda was analysed by bisulfite sequencing PCR (BSP). Many methylation sites were found at the 3′ end sequence of COX3 and at the starting region sequence of ND3, while only a few methylation sites were found at the 3′ end sequence of ND5. The mitochondrial genome was inferred to regulate the energy metabolism through the methylation process. In addition, under Cd2+ stress, mitochondrial DNA methylation was more common, and found during all stress periods (3, 6, 12, 24, 48, 72 and 96 h), while under Cr6+ stress, mitochondrial DNA methylation was less common, mainly occurring after 48 hours of stress. The sensitivity of the mitochondrial genome response to Cd2+ stress was inferred to be greater than that to Cr6+. This study revealed for the first time that methylation occurs in the mitochondrial genome of E. carinicauda in response to heavy metal stress. [ABSTRACT FROM AUTHOR]