Rock Shrimp Research Articles

On the differences between the two widely distributed and closely related rock shrimps Sicyonia japonica Balss, 1914 and S. parajaponica Crosnier, 2003 (Dendrobranchiata, Penaeoidea, Sicyoniidae), with a new record of S. japonica from Taiwan

The rock shrimp Sicyonia japonica Balss, 1914 is recorded from Taiwan for the first time. The availability of many fresh specimens of S. japonica and S. parajaponica Crosnier, 2003 from various localities in the Indo-West Pacific allowed a detailed comparison of the morphology, fresh coloration and genetics between these two closely related species. Their major differences are illustrated by line drawings, micro-computed tomography (micro-CT) images and color photographs. DNA barcoding comparison supports the specific status of these two species and reveals that the western Indian Ocean material of S. japonica may represent another cryptic taxon.

Effects of harvesting on subtidal kelp forests (Lessonia trabeculata) in central Chile

AbstractThe systematic degradation of marine ecosystems is a global phenomenon that has important and diverse consequences including biodiversity loss and reduced ecosystem service provisions. In temperate regions, subtidal kelp forests are dominant ecosystems in rocky coasts, subjected to the influence of local‐scale stressors and regional environmental variation. For example, kelps within the Humboldt Current System are at risk of degradation from live‐harvesting by fisheries. However, limited information exists regarding the long‐term consequences of kelp harvesting, which, in turn, limits the ability to provide effective management and conservation efforts. Here, we examined the ecosystem‐level consequences of the artisanal subtidal Lessonia trabeculata fishery along the coast of central Chile during a 2‐year period, assessing (1) the change in adult and juvenile L. trabeculata density within harvested and nonharvested (control) plots (~90 m2), (2) the impact of L. trabeculata harvesting on reef fish and macroinvertebrate assemblages, and (3) the change in density of the most abundant L. trabeculata‐associated species. The experiment was conducted over a 2‐year period, from December 2016 to May 2019. Approximately 90% of L. trabeculata was removed by an experienced kelp fisherman in experimental plots. After 2 years, L. trabeculata and its associated community showed a lack of recovery in the harvested plots. Within these plots, the average abundance of the rock shrimp, Rhynchocinetes typus, and the herbivorous snail, Tegula tridentata, was greater than in nonharvested plots and the pattern persisted over the study period. The difference in abundance of associated species may be key to the (lack of) recovery of L. trabeculata forests. Our study highlights the impact of L. trabeculata harvesting on associated fauna; however, significant knowledge gaps remain regarding the capacity and time frame to reestablish the original biomass of L. trabeculata, as well as its associated fauna. The management of L. trabeculata fisheries needs to account for ecosystem‐wide impacts in order to better manage and protect vital coastal ecosystems.

Petrology and geochronology of the San Martín de los Andes batholith: Insights into the Devonian magmatism of the North Patagonian Andes

Evidence is growing that a belt of Devonian plutonism is present in the Northern Patagonian segment of the present-day Andes. This plutonism formed along the paleo-Pacific margin of the Gondwana supercontinent. New whole rock chemistry and SHRIMP U–Pb zircon data for plutonic rocks of the San Martín de los Andes batholith (southwestern Argentina) provide insights into the magmatic and tectonic evolution of the southwestern Gondwana margin during the middle Palaeozoic. The San Martín de los Andes batholith was formed between 390 and 374 Ma and intruded into a Lower Paleozoic metamorphic basement that had been previously affected by Late Ordovician-middle Silurian deformation. Most of the batholith is composed of metaluminous, calc-alkaline tonalites and granodiorites, with subordinate volume of peraluminous garnet-bearing granites. Discrete and disperse gabbroic and dioritic rocks hosted in tonalites and granodiorites occur as either microgranular enclaves or syn-magmatic dykes. Tonalitic, granodioritic and granitic rocks develop transitional contacts among them revealing coetaneous building up throughout the plutonic suite, but when interpreting their chemical variability, they are not strictly comagmatic rocks. Collectively, field, petrographic, and geochemical data of the San Martín de los Andes batholith are interpreted to reflect concurrence of crystal fractionation, crustal assimilation and magma mixing in driving petrological diversification. Yet, gabbroic and dioritic rocks in the San Martín de los Andes batholith display geochemical characteristics of calc-alkaline primitive basalts that concur with what is being hypothesized to be a magmatic arc zone for the Devonian period. This study discusses how to interpret the evolution of the San Martín de Los Andes batholith together with other geodynamic models such as the Chaitenia magmatic arc.

Dietary ecology and trophic level of adults of the Chilean angel shark Squatina armata Philippi 1887 in the Central-Eastern Pacific Ocean

As top predators, sharks play an important role in the regulation of marine ecosystems. This study provides information on the feeding ecology and trophic level of the Chilean angel shark Squatina armata in the central-eastern Pacific Ocean. A total of 320 sharks were caught by the artisanal fishery in the Ecuadorian Pacific Ocean and landed in Manta (Ecuador) between November 2003 and October 2004, in which such specimens measured 66 cm to 98.5 cm of total length (TL). The prey included bony fish, elasmobranchs, mollusks, and crustaceans. According to the Prey-Specific Index of Relative Importance (%Psiri), the kolibri shrimp Solenocera agassizii, lizardfish Synodus spp., and peanut rock shrimp Sicyonia picta were the main prey in the diet of S. armata. The sharks which belonged to size I (65–80 cm TL), consumed mostly drum Larimus spp., S. agassizi, and bignose conger Rhynchoconger nitens; while for size II (80–95 cm TL) and size III (95–109 cm TL), sharks fed mostly on S. agassizi, Synodus spp., and S. picta. The results showed that S. armata feeds on the same prey items all year round and it does not display dietary changes. This shark species is a selective predator with functions of a mesopredator (trophic level = 3.20–5.20). It could be classified as mainly piscivorous and carcinophagus, in which this shark species searches for food mainly in benthic and coastal areas. This study highlights the scarcity of knowledge regarding the biology and ecology of S. armata in the central-eastern Pacific Ocean. Additionally, it underlines the need to produce information that will allow adequate management and conservation measures to be implemented for this species by understanding their important feeding spots in coastal areas of Ecuador.

Changes in Shrimping Effort in the Gulf of Mexico and the Impacts to Red Snapper.

Despite a complex management landscape and decades of overfishing, Red Snapper (Lutjanus campechanus) stocks have grown substantially in the Gulf of Mexico and restrictions on the fisheries that catch them are being loosened. This year, annual shrimping effort was allowed to increase by 21% after National Marine Fisheries Service scientists concluded that the resulting bycatch of Red Snapper would only reduce the annual allowable catch in other fisheries by ∼1% and have no impact on population growth. Nonetheless, the recreational fishing sector intensely campaigned against this rule, fueled by wild mischaracterization of shrimp trawl bycatch in media outlets targeting anglers. Here, we aim to elevate the debates surrounding Red Snapper management by presenting scientific and historical context for the potential impacts from shrimping. We discuss our views of the current problems facing Red Snapper and key ecological questions to address for more effective management of this resource.

Distribution and population dynamics of the rock shrimp Sicyonia ingentis and Sicyonia penicillata (Decapoda: Sicyoniidae) in the Gulf of California

Aspects of distribution and population dynamics were assessed in two rock shrimp species of the genus Sicyonia . Samples were obtained by sea bottom trawling in depths from 50 to 460 m during two research cruises on board the B/I BIP XII in the Gulf of California, Mexico. Taxonomic identification of specimens was performed; measurements of individual length and weight data were taken to obtain biometric relationships and length frequencies. Growth parameter estimations were performed adjusting the von Bertalanffy growth model (VBGM), and the recruitment pattern was obtained by the ELEFAN II method. Longevity was estimated with the Taylor equation, natural mortality with six different models, and length at first maturity by the logistic model. A total of 67 fishing trawls were monitored, and 1,330 specimens were caught (65% S. ingentis ; 35% S. penicillata ) in the depth range from 124 to 338 m. Sex ratio (F:M) was 1.0:1.6 for both species; weight and length relationships (both sexes) showed an isometric growth for S. ingentis and positive allometric growth for S. penicillata . Growth parameters and longevity values were moderate (1.71 and 1.81 years) with age at first maturity around six months for both species. The recruitment pattern showed continuous periods all year long, with a notable peak from November to May. Average natural mortality was 2.47 for S. ingentis and 2.35 for S. penicillata . Distribution and population dynamics information reported in this study for these two shrimp species should be considered as base knowledge in subsequent studies on fisheries management in the Gulf of California.

Fisheries assessment within the Gulf of Mexico Large Marine Ecosystem

The status of main fisheries along the Mexican portion of the Gulf of Mexico Large Marine Ecosystem (GoM-LME) was assessed considering the resources’ most relevant aspects, the fisheries fleet, the fisheries market and the problems that they currently face, with the aim of increasing the stakeholders knowledge, to move towards the implementation of an ecosystem management approach in the region. Several recommendations are made for improving the recovery and sustainability of GoM-LME fisheries. With regard to the tuna fishery, the fishery status is completely exploited. Northern brown shrimp and Atlantic seabob fisheries are within the maximum sustainable yield level, whereas the status of northern pink, red-spotted shrimp and brown rock shrimp fisheries are considered as deteriorated. Striped and white mullet fisheries are completely exploited as well as that of shark and skates. The snook fishery is exploited to the maximum sustainable level. Several initiatives are presented based on an ecosystem approach that has been generated to reinforce traditional management plans in order to avoid further deterioration of these resources. Some economic alternatives are identified to increase the profitability of the fisheries of the GoM-LME along the Mexican coast.

<i>Sicyonia Parajaponica</i>, A Rare Record of Rock Shrimp (Crustacea: Decapoda: Penaeoidea: Sicyoniidae), off Thoothukudi Coast of Gulf of Mannar

Earlier records of deep sea rock shrimp Sicyonia parajaponica are from off Chennai, northern part of southeast coast and off Kollam, southwest coast of India. The present report of Sicyonia parajaponica off Thoothukudi waters in Gulf of Mannar extends its distribution further south along southeast coast. It occurred at a depth of 310 m. It has been reported from Gulf of Aden, Phuket in the Andaman Sea, the Philippines, Australia, China and Taiwan.

전암대자율 특성과 SHRIMP 저어콘 U-Pb 연대 측정을 통한 국내 석재와 중국 유사 석재의 비교 연구

전암대자율 특성과 SHRIMP 저어콘 U-Pb 연대 측정을 통한 국내 석재와 중국 유사 석재의 비교 연구

Mating rock shrimp hedge their bets: old males take greater risk, but only after careful assessment of the investment scenario

Mature organisms often have to trade reproductive opportunities against the need to survive, especially in species with exaggerated, sexually selected traits. Life history theory predicts that old males with low residual reproductive value (RRV) would accept greater risk for current reproduction than their younger counterparts. Accordingly, we tested the prediction that, under predation risk, old males of the rock shrimp Rhynchocinetes typus pair with females faster and for a longer time than young males do. We exposed young and old dominant males (in the final ontogenetic stage, called “robustus”) to a female in the absence and presence of a predator. As predicted, older robustus males modified their mating behavior when exposed to a predator. However, in contrast to the prediction, they delayed female seizure under predation risk, possibly to carefully assess the actual threat before initiating female guarding. Once they had established the mate-guarding position, old robustus males did not interrupt it until the end of female spawning and, in the presence of predators, even guarded the female significantly longer than in predator-free treatments. In contrast, younger robustus males did not delay female seizure but abandoned the female repeatedly when a predator was present, suggesting that they perceived and responded to the predation risk. Our results suggest that older robustus males have the experience to assess threats before engaging in risky behaviors that bolster their reproductive success. Although consistent with the theory that low RRV individuals should accept greater reproductive risk, we suggest that old individuals do not recklessly engage in risky behaviors but rather cautiously evaluate the threats before investing in a potentially terminal reproductive event.

Use of rocky intertidal pools by shrimp species in a temperate area

AbstractRocky shores are among the most-intensively studied ecosystems, however, tidal pools remain relatively understudied. This study aims to investigate the habitat use and dynamics of the shrimp species that occur in tidal pools of a North-eastern Atlantic coast, the Portuguese coast, in particular species composition, abundance, seasonality and size structure. Shrimps were sampled monthly from six tidal pools for one year, in the west Portuguese coast. Species diversity was much higher than that found in previous studies, in other parts of the world. The shrimp population comprised 8 species: the European rock shrimp, Palaemon elegans, the common prawn, Palaemon serratus, the Atlantic ditch shrimp, Palaemon varians, the Baltic prawn, Palaemon adspersus, the Oriental shrimp, Palaemon macrodactylus and the relatively rare shrimps Eualus sollaudi, Eualus drachi and Caridion gordoni. Shrimp populations varied seasonally and among pools, with peak numbers in spring and summer. The most abundant species was P. elegans. P. elegans was present in all pools, throughout most of the year. Rare and exotic species were present mostly in spring-summer. Lower mean sizes of all shrimp were registered in the beginning of spring, most often in April or May, and gradually increased until winter. New-recruits of the most abundant species, P. elegans, generally entered the pools in spring and formed a high proportion of the population between April and August. They were responsible for the highest abundance peaks of shrimps occurring in the pools. The species richness and high numbers of juveniles occurring in tidal pools suggest that these environments may be nursery areas for coastal shrimp.

Genetic assessment of parentage in the caridean rock shrimp Rhynchocinetes typus based on microsatellite markers

Over the past decade, the common rock shrimp, Rhynchocinetes typus H. Milne Edwards, 1837, has been the focus of extensive investigations on mating behaviour. The species is now perceived as a model system for the study of reproductive strategies and sexual conflict in crustaceans displaying external fertilization. Using molecular markers, the current study assesses whether social mating behaviour in common rock shrimp translates into true genetic parentage. In a large mesocosm tank with >200 individuals of both sexes, the analysis of 15 families (22 eggs per female) for three informative microsatellites unambiguously confirmed multiple paternity in 11 instances (73%) involving, in each case, two to four males. Where more than one male was identified siring a particular brood, reproductive skew was apparent towards a single individual. Results suggest that multiple paternity in this species results from subordinate male coercive behaviour, female solicitation of multiple male matings or a combination of both.

Matrix-assisted laser desorption ionization mass spectrometry for identification of shrimp

Matrix-assisted laser desorption ionization (MALDI) time of flight mass spectrometry was used to identify shrimp at the species level using commercial mass spectral fingerprint matching software (Bruker Biotyper). In the first step, a mass spectrum reference database was constructed from the analysis of six commercially important shrimp species: Litopenaeus setiferus, Farfantepenaeus aztecus, Sicyonia brevirostris, Pleoticus robustus, Pandalopsis dispar and Pandalus platyceros. This step required a desalting procedure for optimum performance. In the second step, the reference database was tested using 74 unknown shrimp samples from these six species. Correct identification was achieved for 72 of 74 samples (97%): 72 samples were identified at the species level and 2 samples were identified at the genus level using the manufacturer's log score specifications. The MALDI fingerprinting method for the identification of shrimp species was found to be reproducible and accurate with rapid analysis.

Geochronological constraints on Meso- and Neoarchean regional metamorphism and magmatism in the Dharwar craton, southern India

This contribution addresses the time framework of the regional metamorphism in the three crustal provinces making the Archean Dharwar craton. We present results of texturally controlled in situ EPMA chemical dating of monazites, chemical dating of monazite separates, as well as Sm–Nd garnet–whole rock isochrons and SHRIMP U–Pb zircon ages for pelites, amphibolites and granitoids over target areas typical of the various crustal levels of the provinces. The Western Dharwar craton has undergone a major thermal pulse at 2.52Ga followed by slow cooling to ca. 2.4Ga and recorded earlier thermal events around 3.0Ga and 3.1Ga. The Central Dharwar craton records a major high-grade thermal imprint at ca. 2.55–2.51Ga followed by cooling up to 2.45Ga and earlier thermal events at ca. 2.62 and 3.20Ga. In the Eastern Dharwar craton the widespread thermal pulse between 2.55 and 2.52Ga is best recorded. From 2.52Ga on, the entire craton ultimately and contemporaneously undergoes the main event of regional HT–LP metamorphism. The contrasted thermal records of the three provinces reflect their accretion age(s) and their degree of involvement in a wide Latest Archean hot orogen, which sets the capacity of these lithospheric segments to be impact by deformation and mantle fluxes. The tectonic setting of Latest Archean hot orogeny is compatible with active plate margin processes having interacted with mantle instabilities (i.e., plumes?). The tectonic setting of pre-2.5Ga thermal pulses is difficult to assess, but considering their systematic links with documented magmatic pulses, they may have been generated in contexts comparable that of Latest Archean hot orogeny where lateral constrictional flow of hot orogenic crust achieves gravity driven flow, 3D mass redistribution of viscous lower crust submitted to convergence.

Effects of predation and habitat structure on the abundance and population structure of the rock shrimp Rhynchocinetes typus (Caridea) on temperate rocky reefs

Human disturbances, such as overfishing, may disrupt predator–prey interactions and modify food webs. Underwater surveys were carried out at six shallow-water reef barrens in temperate waters of northern-central Chile from October to December 2010 to describe the effects of predation, habitat complexity (low, medium and high) and refuge availability on the abundance and population structure of the rock shrimp Rhynchocinetes typus (Rhynchocinetidae), an important mesoconsumer on subtidal hard substrata. Three sites were within managed (restricted access) areas for fishermen, and three were unmanaged (open-access). Field observations and tethering experiments were conducted to examine the relationship between fish and shrimp abundances, and the relative predation rates on shrimps. Direct effects of predation on R. typus body-size distribution were examined from shrimps collected in the field and fish stomachs. The presence and the abundance of R. typus increased with habitat reef complexity and refuge availability. Shrimp abundance was negatively related to fish abundance in managed areas, but not in open-access areas, where shrimp densities were the highest. Also, predation rates and body-size distribution of shrimps were unrelated, although fish consumed more large shrimps than should be expected from their distribution in the field. R. typus occurred most often in shelters with wide openings, offering limited protection against predators, but providing potential aggregation sites for shrimps. Overall, direct effects of predation on shrimp densities and population structure were weak, but indirect effects on shrimp distribution within reefs appear to have been mediated through behavioural responses. Our study highlights the need to assess both numerical and behavioural responses of prey to determine the effects of predator loss on mesoconsumer populations.Electronic supplementary materialThe online version of this article (doi:10.1007/s00227-012-1994-6) contains supplementary material, which is available to authorized users.

Role of egg surface glycoconjugate in the fertilization of the rock shrimp Rhynchocinetes typus (Milne-Edwards, 1837)

During first gamete interaction, oligosaccharides on the glycoproteins present in oocyte envelopes of the rock shrimp, Rhynchocinetes typus, play an important role in spermatozoon recognition prior to the onset of penetration. These oligosaccharides have terminal monosaccharides that may be recognized by means of specific lectins. A variety of marine species have monosaccharides on their oocyte envelopes, allowing them to interact with the spermatozoa. The number and location of the monosaccharides varies during oocyte maturation. However, this phenomenon has not been studied in shrimp. The present study evaluates the presence and location of monosaccharides on oocyte envelopes during maturation using seven specific lectins conjugated to FITC (GNL, LCA, Con-A BS-1, LTA, GLS-II,DBA); these recognize mannose (α 1-3) mannose, α-mannose, α-glucose, glucose, galactose, fucose, N-acetyl-glucosamine, and N-acetyl- galactosamine, respectively. Participation of these carbohydrates in the fertilization process was determined through the insemination of fresh oocytes with spermatozoa previously incubated with the different monosaccharides that block the active sites of the spermatozoa, inhibiting fertilization. The results showed the presence of N-acetyl-glucosamine and mannose on the oocyte envelopes, indicating that these sugars could be the receptors during the first gamete interaction. The results also suggested that glucose could be a complementary receptor to N-acetyl-glucosamine and mannose since, despite the low concentration of glucose on the envelope, this sugar generated a high degree of fertilization inhibition.

In vitro fertilization of the rock shrimp, Rhynchocinetes typus (Decapoda, Caridea): a review.

This review compiles all the research done on gametes and fertilization in the rock shrimp, R. typus, and describes the sequence of events from the first gamete interaction to zygote formation and the first cleavage of the embryo, with light, fluorescence confocal and electron microscopes. Early studies showed that sperm from the vas deferens have a tack-shape with a "needle-like process" or rigid spike (RS) that extends from a semi-spherical body that contains the arms with chromatin and spines. Upon contact with seawater and by action of Na +, the arms and spines extend, producing an inverted umbrella form of the spermatozoa. The first sperm-oocyte interaction occurs between protein receptors type lectins of the sperm RS and oocyte chorion sperm ligands. These ligands contain residues of α-Glu, Man (α 1-3) Man, α and β-GlcNAc and α-GalNA terminal residues. It was found that α-Man and GlcNAc residues are the ligands that are directly related to the adhesion process and further penetration of sperm. After this first interaction, the RS enters the oocyte envelope by the action of a trypsin-like enzyme, rhynchocinecine, present in the acicular process. Later, arms and spines penetrate the oocyte cytoplasm, where the chromatin of the arms begin to migrate to the central area of the sperm, condensing in a cup-shaped structure near the connecting piece, which forms the male pronucleus.

Anthropogenic structures as a spatial refuge from predation for the invasive bryozoan Bugula neritina

Anthropogenic structures may play an important role in the marine invasion process by providing novel artificial habitats, often out of the reach of common benthic predators. A survey of piers in northern-central Chile revealed a change in the epibenthic assemblage on pilings at differ- ent distances from a rocky shore with abundant grazers and predators. Pilings on soft sediment, away from the rocky shore, were heavily colonized by the invasive bryozoan Bugula neritina. We therefore hypothesized that benthic predators may forage on pilings located on rocky bottom whereas pilings on soft sediment benefit from the absence of generalist benthic predators which do not occur on soft sediment. We examined piling communities using cages directly attached to pilings, where we included or excluded the sea urchin Tetrapygus niger and the rock shrimp Rhyncocinetes typus. Resultant communities differed substantially; a high percentage of bare space occurred in the pres- ence of sea urchins, while turf algae dominated in the presence of shrimp. Both sea urchins and shrimp suppressed the colonization of the invasive B. neritina and, when acting together, totally pre- vented its recruitment. In contrast, invasive bryozoans colonized 95% of the available substratum in cages where predators were excluded. Our results show the important role of benthic generalist pre- dators in limiting the establishment and spread of non-native species on anthropogenic structures. Further, this study highlights the unprecedented role of shrimp grazing in structuring hard-bottom communities.

In vitro fertilization of the rock shrimp, Rhynchocinetes typus (Decapoda, Caridea): a review

This review compiles all the research done on gametes and fertilization in the rock shrimp, R. typus, and describes the sequence of events from the first gamete interaction to zygote formation and the first cleavage of the embryo, with light, fluorescence confocal and electron microscopes. Early studies showed that sperm from the vas deferens have a tack-shape with a "needle-like process" or rigid spike (RS) that extends from a semi-spherical body that contains the arms with chromatin and spines. Upon contact with seawater and by action of Na +, the arms and spines extend, producing an inverted umbrella form of the spermatozoa. The first sperm-oocyte interaction occurs between protein receptors type lectins of the sperm RS and oocyte chorion sperm ligands. These ligands contain residues of α-Glu, Man (α 1-3) Man, α and β-GlcNAc and α-GalNA terminal residues. It was found that α-Man and GlcNAc residues are the ligands that are directly related to the adhesion process and further penetration of sperm. After this first interaction, the RS enters the oocyte envelope by the action of a trypsin-like enzyme, rhynchocinecine, present in the acicular process. Later, arms and spines penetrate the oocyte cytoplasm, where the chromatin of the arms begin to migrate to the central area of the sperm, condensing in a cup-shaped structure near the connecting piece, which forms the male pronucleus.

Transferencia de espermatóforos en el camarón de roca Rhynchocinetes typus (Caridea: Rhynchocinetidae)

The manner in wich males of the rock shrimp Rhynchocinetes typus transfer spermatophores during mating was determined. Fecundation is external. The first and second pair of male pleopods play an active role in the transfer of sperm to the female's sternite. To he participation of these pleopods was determined by amputating the first, second, or both pairs of pleopods of sexually mature males of the type robustus. The number of fertilized eggs in the females was then counted. No fertilization was observed in he females that had mated with males lacking both the first and second pairs of pleopods. Females that had mated with males without either the first or second pair of pleopods presented (1.8% and 0.04%) fewer fertilized eggs than those females that had mated with intact males (100%). These results indicate that both pairs of pleopods participate in the transfer of sperm.