Search Results (10)

Seabob shrimp Xiphopenaeus kroyeri is under heavy capture-pressure in the western Atlantic, requiring periods of fishing suspension to protect the propagation of the species in the wild. This work aims to describe the stages of gonadal development and the ovaries of X. kroyeri in trawling in the southeastern Atlantic Ocean of Brazil associated with climatic characteristics of temperature and precipitation. In total, 3658 specimens were captured in monthly collections from March 2019 to February 2020. The female gonads were classified macroscopically and microscopically according to the maturation stage and correlated with precipitation and temperature data. Five stages of maturation were observed: immature, initial maturation, advanced maturation, mature, and spawned. The highest percentage of mature females was found in May and July, and the average size of the female cephalothorax at the first gonadal maturation was 1.7 cm. The recruitment period was observed in April, with more juveniles. Precipitation showed a negative correlation with the number of mature females. April, May, and July are essential for the life cycle of the X. kroyeri population on the coast of Espírito Santo, Brazil. The results suggest that the current closed season for the species should be reconsidered. Full article

Metapenaeus monoceros is the second most abundant commercially important shrimp species caught along the Saudi Arabian Red Sea coast. However, knowledge of its life history and population dynamics in the region remains limited, posing challenges for sustainable management. This study assessed the growth, maturity, and mortality of M. monoceros based on fishery-independent samples collected from shrimp trawling grounds off Al Qunfudhah and Jizan (October 2022–September 2023). Altogether, 10,859 specimens were examined, with a carapace length (CL) ranging from 7.98 to 49.10 mm and a total weight (W) in the range of 0.41 to 41.28 g. The observed sex ratio was 1.56:1 in favor of females. The CL–W relationship was W = 0.0024∙CL^2.58. The seasonalized von Bertalanffy growth parameters were CL_∞ = 50.66 mm, K = 0.35 year⁻¹, t_anchor = 0.43 years, C = 0.64, and t_s = 0.61 years for females, and CL_∞ = 38.97 mm, K = 0.55 year⁻¹, t_anchor = 0.51 years, C = 0.84, and t_s = 0.39 years for males. Females reached their first sexual maturity at 21.12 mm CL. The exploitation rates (0.60 for both sexes) indicated overfishing. Spawning potential ratio analysis showed that the current fishing pressure reduces the spawning stock biomass to 23% of unexploited levels. A 50% reduction in fishing effort, extended seasonal closures, and selective gear modifications are recommended to rebuild the stock and ensure sustainability. Full article

The habitat characteristics preferred by Penaeus shrimp inhabiting positive (freshwater-dominated) estuaries in North America have been scarcely investigated. Identifying the main environmental factors within the estuary that affect shrimp abundance is relevant to understanding habitat utilization within this particular nursery habitat. This study aimed to evaluate the distribution of penaeid shrimp species along the Soto La Marina River estuary (Northeastern Mexico), analyzing the influence of abiotic factors (water temperature, salinity, and dissolved oxygen) and submerged aquatic vegetation biomass on shrimp populations. A total of 1069 shrimp belonging to four penaeid species (Penaeus aztecus, P. duorarum, P. brasiliensis, and P. setiferus) were collected. Except for P. setiferus, the highest shrimp abundance was near the mouth of the estuary, where the highest salinity and seagrass biomass (Halodule wrightii) were recorded. Salinity and seagrass biomass were the main factors influencing penaeids’ spatial preferences along the estuary, showing significant positive relationships with shrimp abundance in most of the cases examined. Penaeus setiferus was the only species exhibiting peak abundance in an estuarine area devoid of aquatic vegetation (without seagrass or macroalgae) and with a significantly lower salinity level (ca. 22 ppt) than the levels recorded near the river mouth (ca. 28–32 ppt). Differences in osmotic capacity between the species, the protective function of seagrasses against currents, and their role as feeding and refuge habitats could explain the observed spatial distribution in the estuary. Full article

Non-indigenous species (NIS) introduction notoriously threatens the Mediterranean Sea. In addition, Mediterranean coastal lagoons play a crucial role as nurseries for marine species, which new NIS arrivals can threaten. Therefore, monitoring and early warning of NIS presence is essential in preserving biodiversity. An innovative technique for rapid and accurate species identification and biodiversity screening is the application of environmental DNA (eDNA) metabarcoding. In this research, different Penaeidae (Arthropoda, Crustacea, Decapoda) NIS specimens were collected from a Mediterranean coastal lagoon after an early warning about a potentially invasive NIS arising from next-generation sequencing data. DNA barcoding of the DNA extracted from tissue samples and amplified with specifically designed primer pairs led to the recognition of Penaeus aztecus in this NATURA 2000 protected ecosystem for the first time. DNA barcoding from DNA isolated from the water where the living specimens were stored further validated the possibility of identifying P. aztecus starting from eDNA. This approach demonstrated the validity of environmental DNA analysis in the early screening of potentially invasive NIS presence in Mediterranean protected areas and ecosystems. This work describes an applicative example of the efficacy in improving the biomonitoring of lagoon ecosystems using molecular tools and it represents a guideline for the validation of eDNA metabarcoding data for the presence of potentially invasive species. Full article

Crustacean fisheries are gaining prominence globally amid a decline in finfish stocks. Some decapod crustacean species have experienced increased landings in response to shifting market demands and environmental dynamics. Notably, the caramote prawn (Penaeus kerathurus—Forskål, 1775) in the northern Adriatic Sea, Geographical Sub Area (GSA) 17, has risen in both landings and economic importance in recent years. However, despite its significance, comprehensive information on fishery-dependent data, age, and growth in this region remains lacking. To address this gap, this study employs modal progression analysis and the ELEFAN approach, utilizing the “TropFishR” R package and newly developed functions, including bootstrapping procedures. These advancements aim to overcome issues identified in previous versions and enhance the accuracy and reliability of age and growth estimations. The study leverages one year of monthly length-frequency distributions (LFDs) collected from commercial bottom trawls in the northern Adriatic Sea. The results of the analysis confirm the presence of sexual dimorphism in the caramote prawn species, with females exhibiting faster growth rates compared to males. Additionally, the growth performance index supports this observation, further underscoring the importance of accounting for sexual dimorphism in growth modeling and fisheries management strategies. By contributing to a growing body of knowledge on the growth dynamics of the caramote prawn, this study provides valuable insights for sustainable fisheries management in the northern Adriatic Sea. Understanding the age and growth patterns of key crustacean species is essential for developing effective conservation measures and ensuring the long-term health and productivity of marine ecosystems. The findings of this study serve as a foundation for informed decision-making and proactive management practices aimed at preserving the ecological integrity and economic viability of crustacean fisheries in the region. Full article

Vitellogenin (Vtg) is a precursor of yolk proteins in egg-laying vertebrates and invertebrates and plays an important role in vitellogenesis and embryonic development. However, the Vtg family remains poorly characterized in Exopalaemon carinicauda, a major commercial mariculture species found along the coasts of the Yellow and Bohai Seas. In this study, 10 Vtg genes from the genomes of E. carinicauda were identified and characterized. Phylogenetic analyses showed that the Vtg genes in crustaceans could be classified into four groups: Astacidea, Brachyra, Penaeidae, and Palaemonidae. EcVtg genes were unevenly distributed on the chromosomes of E. carinicauda, and a molecular evolutionary analysis showed that the EcVtg genes were primarily constrained by purifying selection during evolution. All putative EcVtg proteins were characterized by the presence of three conserved functional domains: a lipoprotein N-terminal domain (LPD_N), a domain of unknown function (DUF1943), and a von Willebrand factor type D domain (vWD). All EcVtg genes exhibited higher expression in the female hepatopancreas than in other tissues, and EcVtg gene expression during ovarian development suggested that the hepatopancreas is the main synthesis site in E. carinicauda. EcVtg1a, EcVtg2, and EcVtg3 play major roles in exogenous vitellogenesis, and EcVtg3 also plays a major role in endogenous vitellogenesis. Bilateral ablation of the eyestalk significantly upregulates EcVtg mRNA expression in the female hepatopancreas, indicating that the X-organ/sinus gland complex plays an important role in ovarian development, mostly by inducing Vtg synthesis. These results could improve our understanding of the function of multiple Vtg genes in crustaceans and aid future studies on the function of EcVtg genes during ovarian development in E. carinicauda. Full article

The shrimp Penaeus aztecus, native to the western Atlantic, was first reported in the eastern Mediterranean Sea in 2010. New records, from different Mediterranean localities, multiplied in the following years. The accurate search of the literature on non-indigenous species discovered it was misidentified more than once as another alien shrimp, P. semisulcatus, native to the Indo-Pacific region, with the result that its earlier presence in the Black Sea went unnoticed. Morphological characteristics allowing the identification of these two species, the autochthonous P. kerathurus and two other alien Penaeus species present in the Mediterranean, are reprised. The present distribution of P. aztecus based on literature records and surveys carried out in the northern and central Adriatic between 2016 and 2021 is mapped. The unintentional transport of larvae carried in ballast water by transoceanic vessels departing from the U.S. East Coast is suggested as the most probable introduction pathway. The significance of the correct identification of non-indigenous species, a “Descriptor” adopted in the Marine Strategy Framework Directive for determining the good environmental status of marine waters in the European States, is emphasized. Full article

The European spiny lobster is a species of great commercial value, yet a limited scientific knowledge exists on its biology, ecology, and physiology, especially for the stocks from east Mediterranean waters. The northern brown shrimp, a non-indigenous established species, is commercially exploited in regions of the Mediterranean Sea. Both species’ proximate composition and fatty acid profile were assessed for the first time in the Mediterranean region, exhibiting an overall significant statistical difference. Protein, fat, and energy contents were significantly higher in the northern brown shrimp, whereas moisture and ash contents were significantly higher in the European spiny lobster. The proximate composition for both species was well within the reported range for other lobster and prawn species in the Mediterranean Sea. Full article

The Penaeidae family includes some of the most economic and ecological important marine shrimp, comprising hundreds of species. Despite this importance and diversity, the taxonomic classification for penaeid shrimp has constantly been revised, and issues related to the species identification are common. In this study, we implemented DNA barcoding analyses in addition to single-gene species delimitation analyses in order to identify molecular operational taxonomy units (MOTUs) and to generate robust molecular information for penaeid shrimp based on the cytochrome oxidase subunit I (COI) mitochondrial gene. Our final data set includes COI sequences from 112 taxa distributed in 23 genera of penaeids. We employed the general mixed Yule coalescent (GMYC) model, the Poisson tree processes (PTP), and the Bayesian PTP model (bPTP) for MOTUs delimitation. Intraspecific and interspecific genetic distances were also calculated. Our findings evidenced a high level of hidden diversity, showing 143 MOTUs, with 27 nominal species not agreeing with the genetic delimitation obtained here. These data represent potential new species or highly structured populations, showing the importance of including a non-distance-based species delimitation approach in biodiversity studies. The results raised by this study shed light on the Penaeidae biodiversity, addressing important issues about taxonomy and mislabeling in databases and contributing to a better comprehension of the group, which can certainly help management policies for shrimp fishery activity in addition to conservation programs. Full article

This study describes the reproductive cell development and ovarian developmental stages, and identifies the nongerminal components of white shrimp (Penaeus schmitti) caught off the southern coast of Espírito Santo, Brazil. P. schmitti specimens were collected monthly from March 2019 to February 2020, by artisanal fishing. All shrimps were analyzed macroscopically (n = 181) and females were randomly selected monthly (n = 154) for ovarian histological analysis. The ovaries were extracted for visual analysis and then submitted to histological analysis. Macroscopic analysis determined five stages of gonadal development from the color and turgidity of the fresh ovary. Histological observations allowed us to observe five stages of gonadal development: immature, initial development, advanced development, mature and spawning. This information are fundamental for understanding the reproductive aspects of P. schmitti, as well as other penaeid shrimps, in order to promote preservation of natural stocks and provide information to assist in the development of the reproductive potential of native species in captivity. Full article