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Macrobrachium

Macrobrachium is a genus of prawns in the family Palaemonidae, consisting of 319 species (as of 2024) of primarily freshwater decapods that inhabit tropical and subtropical rivers, streams, and brackish waters worldwide, excluding Europe.^[1] These prawns are characterized by their elongated bodies and robust, often asymmetrical second pereiopods (chelae), which are particularly prominent in males and used for defense and mating.^[2] Many species exhibit an amphidromous life cycle, where adults live in freshwater but larvae develop in brackish estuarine environments before migrating upstream.^[3] The genus Macrobrachium was established by Spence Bate in 1868, with the type species Macrobrachium americanum.^[4] Taxonomically, it belongs to the kingdom Animalia, phylum Arthropoda, subphylum Crustacea, class Malacostraca, order Decapoda, suborder Pleocyemata, infraorder Caridea, superfamily Palaemonoidea, and family Palaemonidae.^[4] Species identification relies heavily on morphological traits such as the relative lengths of carpal articles in the second pereiopods, rostral formula, and dentition patterns.^[2] With a global distribution spanning the Americas, Africa, Asia, and Oceania, Macrobrachium species play crucial ecological roles as omnivorous predators and prey in aquatic food webs.^[3] Several Macrobrachium species hold significant economic value, particularly in aquaculture and fisheries; for instance, the giant river prawn (M. rosenbergii) is one of the largest freshwater prawns, reaching over 30 cm in length, and is widely farmed in Asia and other regions for its high market demand.^[3] However, some species have become invasive outside their native ranges, impacting local ecosystems, while others face threats from habitat degradation and pollution.^[3] Research continues to explore their biodiversity, phylogeny, and conservation needs, with molecular studies aiding in species delimitation and resolving taxonomic ambiguities.^[5]

Taxonomy and Etymology

Classification

The genus Macrobrachium belongs to the kingdom Animalia, phylum Arthropoda, class Malacostraca, order Decapoda, suborder Pleocyemata, infraorder Caridea, family Palaemonidae.^[4] Within the Palaemonidae, Macrobrachium stands as one of the most species-rich genera, encompassing approximately 319 species and subspecies primarily adapted to freshwater and brackish environments worldwide.^[1] The type species of the genus is Macrobrachium americanum Spence Bate, 1868, designated by subsequent designation based on specimens from Central America.^[4]^[6] The genus name Macrobrachium, derived from the Greek words makros (long) and brachion (arm), reflects its characteristic elongated appendages.^[7]

History and Etymology

The genus Macrobrachium was first described in 1868 by the British carcinologist Charles Spence Bate in the Proceedings of the Zoological Society of London, where he established it as a distinct genus to accommodate four new species of freshwater prawns, emphasizing their characteristic elongated second pereiopods as a key diagnostic feature.^[4] Prior to Bate's work, species now placed in Macrobrachium had been classified under broader or unrelated genera; for example, Macrobrachium carcinus, one of the most widespread species, was originally named Cancer carcinus by Carl Linnaeus in his 1758 Systema Naturae.^[8] The etymology of Macrobrachium stems from Ancient Greek roots: makros (μακρός), meaning "long" or "large," combined with brachion (βραχίων), meaning "arm," directly referencing the disproportionately long second pair of pereiopods, which often develop into robust, claw-bearing appendages in males.^[2] This naming convention highlights the morphological trait that Bate used to differentiate the genus from other palaemonid shrimps, such as those in the genus Palaemon.^[4] Throughout the late 19th century, taxonomic exploration accelerated with additional species descriptions, including Macrobrachium rosenbergii by J.G. de Man in 1879, which later became central to aquaculture due to its large size and euryhaline adaptations.^[9] The 20th century saw significant refinements, notably in L.B. Holthuis's 1950 monograph on Indo-Pacific palaemonids from the Siboga Expedition, which synthesized morphological data and resolved many synonymies to stabilize genus-level classification.^[10] More recent advancements, including molecular phylogenetics, have further clarified evolutionary relationships and prompted revisions, addressing ongoing challenges in species delimitation.^[2] These shifts reflect a progression from morphology-based groupings to integrated approaches incorporating genetics and biogeography.^[2]

Physical Description

Morphology

Macrobrachium species exhibit an elongated body structure typical of caridean shrimps, consisting of a cephalothorax covered by a hard carapace and a distinct abdomen divided into six segments. The carapace encloses the branchial chamber and often features antennal and hepatic spines, while the abdomen is flexible, aiding in locomotion.^[11] A prominent rostrum projects forward from the cephalothorax, armed with dorsal and ventral teeth that vary in number and arrangement across species (typically 7–15 dorsal, including 2–4 behind the orbit, and 1–10 ventral), serving as a key diagnostic trait for the genus.^[2]^[11] The appendages of Macrobrachium are biramous and segmented, adapted for sensory perception, locomotion, and manipulation. The cephalothorax bears paired antennules and antennae for chemosensory and mechanosensory functions, followed by three pairs of maxillipeds and five pairs of pereiopods; the first pereiopod pair is chelate for handling food, while the second pair forms robust chelipeds that are a hallmark of the genus, often extremely enlarged in males for defense and mating rituals.^[3]^[12] The abdomen features five pairs of pleopods (swimmerets) for swimming and respiration, with the sixth somite bearing uropods that, together with the telson, form a fan-like tail for rapid escape movements.^[11] Sexual dimorphism is evident in the chelae size of the second pereiopods, which are disproportionately larger in males compared to females.^[3] Most Macrobrachium species range from 5 to 15 cm in total length, though the largest, such as M. rosenbergii, can reach up to 33 cm, establishing the genus's scale among freshwater prawns.^[12]^[11] Coloration is generally translucent in juveniles, transitioning to greenish-brown or grayish hues in adults, with variations influenced by species and environmental factors, often featuring subtle banding or spots for camouflage.^[2]^[11]

Sexual Dimorphism

Sexual dimorphism in the genus Macrobrachium is pronounced, particularly in body size and secondary sexual characteristics of the appendages, reflecting adaptations to reproductive roles. Males generally exhibit larger overall body sizes compared to females, with more robust and elongated chelae on the second pereiopods, which are the primary walking legs modified into claws. These chelae in males can extend up to several times the length of the body in some species, serving as key structures for mate competition.^[11]^[13] In females, the chelae on the second pereiopods are notably smaller and less developed, while the abdomen is broader to accommodate egg carrying. The swimmerets, or pleopods, in females form a specialized brood pouch known as the marsupium, created by elongated pleura that enclose and ventilate fertilized eggs until hatching. This structure is absent in males, whose abdomens are narrower. The second pereiopods in both sexes share a basic morphology but diverge significantly in size and function due to these sex-specific traits.^[11]^[14]^[13] The pronounced male chelae play critical behavioral roles, including agonistic encounters to establish dominance and courtship displays to attract females, often accompanied by color variations in the claws during mating seasons. For instance, in Macrobrachium rosenbergii, males can attain a total length of up to 32 cm, exceeding females which reach about 25 cm. These differences underscore the genus's reliance on sexual selection for reproductive success.^[11]^[13]^[15]

Habitat and Distribution

Geographic Range

The genus Macrobrachium exhibits a pantropical distribution, primarily native to freshwater and brackish systems across Central and South America, Africa, and the Indo-Pacific region extending from India through Southeast Asia to Pacific islands and Oceania, with no native presence in Europe.^[16] This disjunct pattern reflects the genus's adaptation to tropical and subtropical climates, where species inhabit lowland riverine and estuarine environments.^[3] With over 300 species recognized worldwide as of 2025, the genus has a broad ecological footprint in these regions.^[1] Diversity is particularly high in Southeast Asia, where the genus thrives in complex river networks; for instance, in countries such as India and China, contributing significantly to the Indo-Pacific hotspot.^[17] In contrast, Africa supports fewer species, though distinct taxa occur in West African rivers and the Nile basin.^[17] South America, especially the Amazon basin, also features substantial diversity, with species assemblages varying across major drainages.^[16] Human-mediated introductions have expanded ranges beyond native areas, notably M. rosenbergii, which has been translocated for aquaculture to parts of Africa, the Americas, and other regions since the 1970s, establishing self-sustaining populations in some introduced sites.^[18] Many Macrobrachium species demonstrate endemism, being confined to specific river basins such as the Amazon in South America or the Mekong in Southeast Asia, where geological isolation has fostered localized adaptations.^[19]^[20] Natural dispersal historically occurred through ancient river connections and vicariance events, such as paleo-drainages in the Neotropics, facilitating the genus's colonization of isolated freshwater habitats during periods of tectonic stability.^[21] These patterns highlight the interplay between geological history and contemporary anthropogenic influences in shaping the genus's global range.^[16]

Environmental Preferences

Macrobrachium species primarily inhabit freshwater environments such as rivers, streams, lakes, and wetlands characterized by slow to moderate water flow.^[22] These prawns often associate with vegetated areas, including the roots of aquatic plants like water hyacinth, which provide shelter and foraging opportunities.^[23] In terms of water quality, Macrobrachium species tolerate a temperature range of 20–30°C, with optimal growth observed between 24–28°C in natural habitats.^[24] They prefer a pH of 6.5–8.5, showing highest survival and development at neutral to slightly alkaline levels around 7.5–8.0, while low pH below 6.5 can depress growth and increase mortality in larvae.^[25] Dissolved oxygen levels as low as 2–3 mg/L are tolerated by some species through air-breathing adaptations, though levels above 5 mg/L support better physiological performance.^[26] For catadromous species like Macrobrachium rosenbergii, larvae exhibit euryhaline tolerance, requiring brackish water (5–15 ppt salinity) for development, whereas juveniles and adults thrive in freshwater with salinity near 0 ppt.^[27] Microhabitat preferences vary by life stage; juveniles often occupy clear, upstream freshwater reaches with rocky or vegetated substrates for hiding, while adults favor downstream areas that may include brackish zones, where they burrow into mud or seek cover under rocks and debris.^[28] Many species, particularly in tropical regions, display amphidromous or catadromous migrations to complete their life cycle, with ovigerous females descending to brackish waters for larval release before juveniles migrate upstream.^[29] These adaptations enable exploitation of diverse aquatic niches while maintaining population connectivity.^[28]

Life Cycle and Biology

Reproduction and Development

Reproduction in the genus Macrobrachium typically occurs in freshwater habitats, where males grasp females using their enlarged chelae to facilitate mating, often mounting them shortly after the female's molt when her exoskeleton is soft.^[30] During copulation, the male deposits spermatophores on the female's thoracic sternum between the walking legs, and as she later extrudes eggs, they pass through this sperm mass for fertilization.^[31] Fertilized eggs are then attached to the female's pleopods under the abdomen, forming a "berried" condition that lasts until hatching.^[32] Fecundity in Macrobrachium species varies widely with body size and life-history strategy, ranging from a few hundred eggs in smaller, strictly freshwater species to over 500,000 in larger amphidromous forms like M. rosenbergii.^[33] Amphidromous species produce numerous small eggs to compensate for high larval dispersal losses, while freshwater species with abbreviated development yield fewer, larger eggs with more yolk reserves.^[34] Developmental patterns differ markedly across the genus, reflecting adaptations to freshwater constraints. Strictly freshwater species exhibit abbreviated or direct development, hatching as advanced postlarvae or juveniles capable of immediate upstream migration without salinity dependence.^[34] In contrast, catadromous and amphidromous species undergo indirect development with planktonic zoea larvae requiring brackish water for survival and metamorphosis; females may migrate downstream to estuaries for spawning, or release larvae into currents that carry them seaward.^[34] Zoea larvae progress through 5 to 20 stages—typically 10 to 15 in common species like M. rosenbergii and M. lar—before molting into postlarvae that migrate upstream to freshwater.^[35] These early stages rely on limited yolk for energy, making timely access to brackish conditions critical.^[34] Breeding seasons in tropical Macrobrachium populations are often synchronized with monsoon or rainy periods, which increase river flow and facilitate larval transport to brackish zones.^[36] This timing enhances dispersal success but can vary by region and species, with some subtropical forms reproducing year-round under favorable conditions.^[31] Post-hatching, Macrobrachium species provide no parental care, with females releasing larvae directly into the water column.^[34] Larval phases experience high mortality, often exceeding 90% in the wild due to predation, starvation, or failure to reach suitable salinities within their short yolk-limited window of 2 to 5 days.^[34]

Growth and Diet

Juvenile Macrobrachium prawns exhibit rapid growth following metamorphosis from the post-larval stage, with individuals reaching sexual maturity in approximately 3 to 6 months under optimal conditions. This accelerated growth phase is characteristic of the genus, enabling postlarvae to quickly transition to a benthic lifestyle in freshwater habitats. Growth rates vary by species, but in the widely studied M. rosenbergii, juveniles can attain marketable sizes of 20–30 grams within 4–5 months during pond culture.^[37]^[38]^[33] Growth is significantly influenced by environmental factors such as temperature and food availability, with optimal temperatures ranging from 28–31°C promoting the highest rates. At temperatures below 20°C, growth slows considerably, limiting production in temperate regions to seasonal cycles of 4–5 months. Prawns undergo periodic molting to facilitate size increase, with juveniles typically molting every 2–4 weeks depending on size, temperature, and nutritional status; higher temperatures accelerate molting frequency, while lower ones extend inter-molt intervals. Male morphotypes in species like M. rosenbergii further modulate growth through social hierarchies, where dominant "blue claw" males can suppress the growth of smaller individuals.^[33]^[38]^[39] Macrobrachium species are omnivorous scavengers, primarily consuming a mix of algae, detritus, plant matter, and small invertebrates such as snails, insects, and worms. Foraging occurs predominantly at night, with prawns using their chelae to manipulate food items from the substrate. This opportunistic feeding strategy allows them to exploit diverse resources in riverine and pond environments. In some species, such as M. rosenbergii, individuals may also prey on fish eggs and fry, positioning them at a secondary consumer trophic level within aquatic food webs.^[33]^[40]^[41] In aquaculture settings, Macrobrachium prawns have high nutritional requirements, particularly for protein, with diets optimally formulated at 30–35% crude protein to support maximal growth and survival. Lower protein levels reduce feed efficiency and body composition quality, while excessive amounts lead to wasted resources. These requirements reflect their natural omnivorous habits but are adjusted in captivity to include formulated feeds supplemented with fishmeal or plant-based proteins.^[42]^[43]^[44]

Ecology

Role in Ecosystem

Macrobrachium species contribute significantly to aquatic biodiversity in tropical and subtropical freshwater ecosystems, where their high species diversity—approximately 300 described species—supports complex food webs by serving as both prey for fish and predators of smaller invertebrates. This diversity enhances ecosystem resilience and stability, as different species occupy varied niches across rivers, streams, and wetlands.^[17] Additionally, Macrobrachium shrimps act as bioindicators of water quality, bioaccumulating contaminants such as lead, mercury, and nitrates from polluted environments, which reflect broader pollution levels in habitats like urban rivers. For instance, in the Iponan River, Philippines, elevated lead concentrations up to 1.36 ppm and nitrates exceeding 800 ppm in shrimp tissues indicated severe anthropogenic impacts, exceeding regulatory standards.^[45]^[46] As detritivores, Macrobrachium shrimps play a crucial role in nutrient cycling by processing leaf litter and organic matter, accelerating decomposition and releasing nutrients like nitrogen and phosphorus into the water column.^[47] Their omnivorous diet further aids this process by incorporating algae, detritus, and small prey, thereby maintaining benthic habitat cleanliness and supporting primary production. Macrobrachium species also function as effective predators, particularly in controlling populations of snails that serve as intermediate hosts for schistosomiasis, a major parasitic disease. Species like Macrobrachium rosenbergii prey voraciously on vector snails such as Biomphalaria glabrata and B. tenagophila, consuming up to 3.5% of their body weight in snails daily, even when alternative food is available. Field and modeling studies in regions like Senegal demonstrate that stocking prawns in affected waterways can reduce snail densities and schistosome transmission by up to 50-80%, offering a biological control strategy without impacting human health via prawn consumption.^[48]^[49] Through burrowing and association with aquatic vegetation, Macrobrachium shrimps engage in habitat engineering, creating microhabitats that provide shelter for smaller organisms like insect larvae and juvenile fish. In stream sediments, their bioturbation reduces inorganic matter accumulation and promotes organic degradation, fostering diverse benthic communities. In some river systems, Macrobrachium dominates biomass as macroconsumers, exerting keystone influences on invertebrate and fish dynamics; for example, in Puerto Rican streams, their exclusion at mid-elevations led to significant increases in algal biovolume and shifts in community structure, underscoring their role in top-down control.^[50]^[51] Recent molecular phylogenetic studies, as of 2025, continue to refine species delimitation and highlight cryptic diversity, enhancing understanding of their ecological contributions.^[52]

Interactions and Threats

Macrobrachium species face predation from various aquatic and terrestrial predators, influencing their behavior and population dynamics. Fish such as cichlids and other omnivorous species prey on juvenile and smaller prawns, while birds like herons and kingfishers target adults in shallow waters. Amphibians, including frogs, occasionally consume small individuals, particularly during vulnerable larval stages. In high-density populations, cannibalism is prevalent among conspecifics, where larger prawns prey on smaller ones, exacerbating mortality rates under stressed conditions such as limited food or shelter.^[53]^[54]^[55] Competition occurs with other decapod crustaceans, including native crayfish and invasive species like the red swamp crayfish (Procambarus clarkii), which vie for similar resources in shared habitats. Some Macrobrachium species, notably M. rosenbergii, exhibit invasive potential in non-native ranges, outcompeting indigenous prawns through aggressive foraging and rapid reproduction, leading to shifts in local biodiversity. For instance, escapes from aquaculture in Brazil have established feral populations that displace native decapods.^[56]^[57] Major threats to Macrobrachium populations include habitat fragmentation caused by dams, which block upstream migration essential for reproduction and downstream larval dispersal. This disruption has led to population declines, as seen in species like M. ohione, where river control structures impede juvenile migration and reduce connectivity between freshwater and estuarine habitats. Additionally, such barriers indirectly increase human health risks by diminishing prawn predation on schistosomiasis-vector snails. Pollution from heavy metals like cadmium and pesticides impairs growth, reproduction, and survival, with bioaccumulation causing physiological stress in exposed populations. Overfishing in tropical rivers depletes stocks, particularly for commercially valuable species like M. rosenbergii, altering age structures and recruitment. Climate change exacerbates these issues by altering river flows and increasing temperatures, which disrupt migration cues and elevate metabolic demands, potentially reducing larval survival in species such as M. amazonicum.^[58]^[59]^[60]^[61]^[62]^[63]

Economic and Cultural Significance

Aquaculture and Fisheries

Macrobrachium species, particularly M. rosenbergii, play a significant role in global aquaculture, with production exceeding 300,000 metric tons annually as of the early 2020s, reaching 337,000 tonnes in 2022.^[64]^[65] Asia dominates this sector, accounting for over 90% of output, led by China (approximately 196,000 tons in 2023), India, and Thailand.^[66]^[65] This species constitutes the vast majority of farmed Macrobrachium, valued for its adaptability to freshwater systems and high growth potential in captivity, where individuals can reach marketable sizes of 30-50 grams within 4-6 months. Recent advances in all-male monosex biotechnology and selective breeding have further enhanced growth rates and production efficiency.^[65]^[67] Farming practices for M. rosenbergii typically involve a two-stage process: hatchery production of larvae and postlarvae followed by pond grow-out. Hatchery techniques, developed in the 1960s and refined in the 1970s, rely on brackish water (salinity 10-15 ppt) for larval rearing through 11-12 zoeal stages, after which postlarvae are acclimated to freshwater via salinity gradients for stocking in earthen ponds.^[68] Pond culture uses densities of 20,000-50,000 postlarvae per hectare, with supplemental feeding of formulated pellets and management of water quality to achieve yields of 1-3 tons per hectare per crop.^[67] Wild fisheries for Macrobrachium remain important for subsistence in regions like Africa and the Americas, where species such as M. macrobrachion and M. amazonicum are harvested from rivers and estuaries using traps and nets. In West African rivers, these fisheries support local communities but face challenges from overexploitation, leading to declining population sizes.^[69] Similarly, in the Amazon basin, artisanal capture provides essential protein and income for indigenous groups, though habitat degradation and unregulated fishing contribute to stock depletion.^[70] The economic significance of Macrobrachium aquaculture and fisheries stems from its high market value, driven by the prized firm texture and sweet flavor akin to lobster, fetching prices of $5-10 per kilogram in Asian markets. Global production in 2022 generated over $2.57 billion, creating substantial employment in rural areas of developing countries like Bangladesh and Vietnam, where it supports livelihoods for millions through farming, processing, and trade.^[65]^[71]

Culinary and Other Uses

Species of the genus Macrobrachium, particularly M. rosenbergii (giant river prawn) and M. amazonicum (Amazon river prawn), are prized in various culinary traditions for their sweet, tender meat, which is rich in protein and low in fat, providing a nutritious seafood option comparable to other prawns. In Southeast Asian cuisines, such as those of Thailand and India, these prawns are commonly prepared by grilling, stir-frying, or simmering in curries and sauces to highlight their delicate flavor. In the Amazon region of Brazil, M. amazonicum holds significant cultural importance as a staple food for traditional communities across all social classes, often consumed fresh, boiled, or processed into canned products like Amazon sauce to preserve its quality during storage.^[72]^[19] Beyond consumption, Macrobrachium species serve diverse non-aquacultural purposes. Certain species, including M. rosenbergii and M. lanchesteri, are utilized as ornamental invertebrates in freshwater aquariums due to their striking appearance and active behavior, though they require spacious setups to accommodate their growth and territorial nature. In regions like the southern United States, M. ohione (Ohio shrimp) is harvested specifically as live bait for recreational fishing, valued for its effectiveness in attracting sportfish in rivers and streams. Folk remedies in some Amazonian communities attribute anti-inflammatory properties to extracts from Macrobrachium species, though scientific validation remains limited. Market trends for Macrobrachium reflect growing global demand, with major Asian producers like China and India exporting significant volumes to markets in Europe and the United States, where they command premium prices for their quality. Sustainability efforts are emerging, with certifications such as Aquaculture Stewardship Council (ASC) standards being adopted in exporting countries like Indonesia and Bangladesh to address environmental concerns and ensure traceability in supply chains.^[64]^[73]^[74]

Species Diversity

Overview of Species

The genus Macrobrachium Bate, 1868, is one of the most speciose genera within the family Palaemonidae, encompassing approximately 319 accepted species as documented in the World Register of Marine Species (WoRMS) database as of 2024.^[1] This count reflects the genus's extensive radiation across tropical and subtropical freshwater and brackish habitats globally, with the total number continuing to grow due to ongoing taxonomic discoveries; for instance, two new cavernicolous species (M. guizhouense and M. parvum) were described from karst caves in Guizhou and Guangxi provinces, China, in 2025, highlighting underexplored subterranean diversity.^[75] These additions underscore the dynamic nature of Macrobrachium taxonomy, where molecular and morphological revisions frequently reveal cryptic lineages previously overlooked. Species diversity within Macrobrachium exhibits pronounced biogeographic patterns, with the highest concentrations in the Indo-Pacific region, where over 100 species have been recorded across diverse riverine and estuarine systems. In contrast, the Neotropics support a comparatively lower diversity of around 50-60 species, primarily adapted to river basins in Central and South America.^[76] West Africa represents a third, smaller center of endemism with fewer than 20 species, illustrating the genus's pantropical distribution shaped by historical vicariance and dispersal events.^[28] Such hotspots are influenced by environmental heterogeneity, including seasonal monsoons and floodplain dynamics in the Indo-Pacific, which foster adaptive radiations. Conservation assessments for Macrobrachium species remain limited, with only a small fraction evaluated by the International Union for Conservation of Nature (IUCN); of those assessed, many are classified as Data Deficient due to insufficient ecological data. Habitat loss from deforestation, dam construction, and water pollution poses significant threats, driving population declines in several species and contributing to localized extirpations, particularly in fragmented river systems.^[77] Identification of Macrobrachium species presents notable challenges owing to high morphological similarities, especially among sympatric forms that exhibit subtle variations in rostral teeth, cheliped structure, and body proportions.^[78] These ambiguities often necessitate the integration of molecular tools, such as DNA barcoding and phylogenetic analyses based on mitochondrial genes like COI, to delineate cryptic species and resolve taxonomic uncertainties.^[79]

Notable Species

Among the approximately 319 species in the genus Macrobrachium, several stand out due to their size, ecological roles, or economic value. Macrobrachium rosenbergii, commonly known as the giant freshwater prawn, is the largest species in the genus, with males reaching a maximum total length of 320 mm and females up to 250 mm. Native to the Indo-Pacific region, including rivers and estuaries from India to Southeast Asia, this catadromous species migrates to brackish water for larval development before returning to freshwater habitats as juveniles and adults. It dominates global aquaculture production, with approximately 314,000 metric tons farmed as of 2021, primarily in Asia, due to its rapid growth and high market demand.^[41]^[15]^[80]^[64] Macrobrachium americanum, the type species of the genus, inhabits rivers and streams along the Pacific coast of Central and South America, from Mexico to Peru. This amphidromous prawn attains a maximum total length of 250 mm in males and 193 mm in females, supporting local fisheries in countries like Mexico, Guatemala, and El Salvador through capture and emerging culture practices. Its abundance in coastal-river systems underscores its role in regional biodiversity and potential for sustainable aquaculture expansion.^[81]^[82]^[83] In the Neotropics, Macrobrachium carcinus, the Amazon river prawn, is a prominent amphidromous species distributed from Florida to southern Brazil, including key Amazon basin rivers. It grows to a maximum length of 300 mm, making it one of the largest freshwater prawns in the Americas, and occupies diverse habitats from clear streams to turbid estuaries. This species contributes significantly to Amazonian biodiversity as a keystone crustacean in food webs and supports artisanal fisheries, though overexploitation poses threats to wild populations.^[84]^[85]^[86] Other notable species include Macrobrachium latidactylus, the scissor river prawn of the Western Pacific, which reaches up to 181 mm and thrives in estuarine and inshore marine waters, valued in local fisheries for its distinctive broad claws. In Africa, Macrobrachium vollenhovenii, the African river prawn, inhabits West African coastal rivers and attains lengths of over 150 mm, serving as a vital fishery resource in countries like Nigeria and Senegal while showing potential for aquaculture and as a biocontrol agent against schistosomiasis vectors, though introductions raise concerns about invasiveness. Comparisons across these species highlight variations in maximum size—from the colossal M. rosenbergii to the more modest M. vollenhovenii—along with habitat preferences (freshwater vs. brackish influences) and human relevance, primarily through aquaculture dominance in Asian species versus biodiversity and local harvest in American and African ones.^[87]^[88]^[89]^[90]

References

[1]
The genus Macrobrachium (Crustacea, Caridea, Palaemonidae ...
Jul 24, 2019 · The genus Macrobrachium Spence Bate, 1868 comprises 242 species and subspecies inhabiting fresh to brackish environments (De Grave and Fransen ...
[2]
The genus Macrobrachium (Crustacea, Caridea, Palaemonidae ...
Jul 24, 2019 · The taxonomy of the genus Macrobrachium is mainly based on morphological characters, such as the relative length of the articles of the second ...
[3]
Macrobrachium - an overview | ScienceDirect Topics
Macrobrachium refers to a genus of freshwater shrimp, which are associated with the roots of aquatic plants like Pontederia crassipes, serving as important ...
[4]
Macrobrachium Spence Bate, 1868 - WoRMS
Macrobrachium Spence Bate, 1868 · Biota · Animalia (Kingdom) · Arthropoda (Phylum) · Crustacea (Subphylum) · Multicrustacea (Superclass) · Malacostraca (Class) ...
[5]
Molecular phylogeny and species delimitation of the freshwater ...
In this study, the “pilimanus” species group of Macrobrachium sensu Johnson (1958) was studied using specimens collected from montane streams of Thailand.
[6]
Macrobrachium americanum Spence Bate ... - Marine Species Traits
Macrobrachium americanum Spence Bate, 1868 ; Animalia (Kingdom) ; Arthropoda (Phylum) ; Crustacea (Subphylum) ; Multicrustacea (Superclass) ; Malacostraca (Class) ...
[7]
MACROBRACHIUM Definition & Meaning - Merriam-Webster
The meaning of MACROBRACHIUM is a genus of large stout chiefly tropical shrimps including one (M ... Word History. Etymology. New Latin, from macr- + ...
[8]
https://www.marinespecies.org/aphia.php?p=taxdetails&id=220122
[9]
https://www.marinespecies.org/aphia.php?p=taxdetails&id=220137
[10]
Macrobrachium yui Holthuis, 1950 - GBIF
Macrobrachium yui Holthuis, 1950. Published in: Holthuis, L. B. (1950). The Decapoda of the Siboga Expedition. Part X. The Palaemonidae collected by the Siboga ...
[11]
Identifying Macrobrachium rosenbergii from other freshwater prawn ...
it is the largest known of all Macrobrachium species, adult males having been reported with a total body length of up to 33 cm, and adult females of up to 29 cm ...
[12]
Morphological and molecular characterization of freshwater prawn ...
Macrobrachium is a large crustacean genus of high economic importance. Morphological characterization and molecular characterization of prawns of this genus ...Missing: anatomical | Show results with:anatomical
[13]
sexually dimorphic structures of the malaysian prawn - jstor
males are considerably longer, more robust, and have larger spines than those of females. This sexual dimorphism is evident to anyone seeing the species. ...
[14]
(PDF) Sexual dimorphism in the carapace shape and length of the ...
Aug 7, 2025 · In this group, especially in some species of the genus Macrobrachium, males tend to be larger in body and cheliped size than females (Taddei et ...
[15]
FAO - Macrobrachium rosenbergii
Males can reach total length of 320 mm; females 250 mm. Body usually greenish to brownish grey, sometimes more bluish, darker in larger specimens.Missing: maximum | Show results with:maximum
[16]
[PDF] Zootaxa,Freshwater prawns of the genus Macrobrachium Bate, 1868...
Apr 25, 2007 · The genus Macrobrachium includes approximately 200 species of prawns and has the largest number of species of all Palaemonid genera. Its ...
[17]
Diversity, distribution, and conservation status of Macrobrachium ...
Aug 21, 2025 · Macrobrachium lanchesteri was the most abundant and widely distributed species (LD = 50%), particularly in lentic habitats. Species such as ...
[18]
Macrobrachium rosenbergii (giant freshwater prawn)
Oct 18, 2024 · FAO (2009) describe the species as follows: “Males can reach total length of 320 mm; females 250 mm. Body usually greenish to brownish grey, ...
[19]
An update of the amazon prawn (Macrobrachium amazonicum ...
Jan 29, 2021 · The prawn Macrobrachium amazonicum has been considered a successful colonizing species of freshwater environments beyond its native range; ...
[20]
Genetic isolation among populations of the landlocked freshwater ...
The landlocked freshwater shrimp Macrobrachium yui has a high economic value for the rural villages in the northern area of Laos. In order to manage shrimp ...
[21]
Macrobrachium amazonicum (Decapoda, Palaemonidae)
Aug 28, 2025 · amazonicum possibly evolved in the Amazon or Orinoco basin after the formation of river systems considered precursors to the ancient paleo ...
[22]
[PDF] Diversity, distribution, and conservation status of Macrobrachium ...
Aug 21, 2025 · S: Number of species; ... Figure 3: Freshwater shrimp species of the genus Macrobrachium occur in Aceh waters: (a) Macrobrachium australe.
[23]
[PDF] Study of Habitat ecology of freshwater prawn (M. rosenbergii) in ...
Understanding the habitat preferences, population dynamics, and ecological requirements of these prawns is essential for implementing targeted conservation ...
[24]
Rapid determination of the physiological temperature range for the ...
Mar 15, 2025 · We developed a method for rapidly determining the physiological temperature range of giant freshwater prawn (Macrobrachium rosenbergii).<|control11|><|separator|>
[25]
https://doi.org/10.1016/j.heliyon.2022.e09989
[26]
https://doi.org/10.55730/1300-0179.3142
[27]
Transcriptome Analysis Reveals the Molecular Response to Salinity ...
Apr 29, 2022 · Transcriptome Analysis Reveals the Molecular Response to Salinity Challenge in Larvae of the Giant Freshwater Prawn Macrobrachium rosenbergii.Missing: catadromous amphidromous
[28]
Neotropical Macrobrachium (Caridea: Palaemonidae): On the ...
Our estimate of a Mesozoic origin of Macrobrachium is consistent with the fact that the earliest reliably dated caridean shrimp fossils were found in Cretaceous ...
[29]
Macrobrachium nipponense - Marine Invasions research at SERC
Life History The fresh and brackish water shrimps of the genus Macrobrachium have evolved from marine ancestors. While many are land-locked and complete their ...
[30]
[PDF] Mating Behaviour in Different Size Males of Macrobrachium idae ...
Dec 12, 2013 · In all of these populations, extreme sexual dimorphism involving large size and elongated chelae in males suggests that competition for mates is ...
[31]
Assessing reproductive biology of Macrobrachium lamarrei in ... - NIH
The aim of the research is to explore various reproductive aspects (size at sexual maturity, reproductive period and fecundity) of M. lamarrei in the Ganges ...Missing: parental | Show results with:parental
[32]
chapter 3. broodstock
The eggs of Macrobrachium rosenbergii are carried by the ('berried') females until they are ready to hatch; as they ripen, they change from orange to grey ...
[33]
[PDF] Giant River Prawn (Macrobrachium rosenbergii)
There is adequate information available on the biology and distribution of Macrobrachium rosenbergii, especially in relation to its use in aquaculture. It has ...
[34]
Anfidromía en camarones: un ciclo de vida entre los ríos y el mar
La anfidromía es un ciclo de vida común en camarones tropicales y subtropicales de agua dulce, en que los adultos viven, se aparean y desovan embriones pequeñ ...
[35]
Complete larval development of the Monkey River Prawn ...
This study documents the complete larval development of the Monkey River Prawn Macrobrachium lar using a new greenwater rearing technique.Missing: mating | Show results with:mating
[36]
https://www.tandfonline.com/doi/full/10.1080/07924259.2025.2458019
[37]
Freshwater Prawns: Biology and Life History
Females generally become reproductively mature within 6 months. Mating can occur only between hard-shelled males and soft-shelled females (i.e., females who ...Missing: time | Show results with:time
[38]
Freshwater Prawn Production in Missouri | MU Extension
... juvenile prawns, energy and labor. Weather also plays an important role, as temperatures influence the length of the growing season and can impact profitability ...Missing: patterns | Show results with:patterns
[39]
Effect of temperature on the survival and growth of freshwater ...
Aug 10, 2025 · The survival rate was highest at 20°C and 25°C, decreasing at the lowest temperature. The number of molts increased at higher temperatures.
[40]
Natural diet of Macrobrachium brasiliense (Crustacea, Decapoda) in ...
The results obtained confirm an omnivorous diet for the species and suggest that the composition and proportion of items may vary depending on the size of the ...
[41]
brief notes on the giant freshwater prawns as an object of farming
Freshwater prawn (Macrobrachium rosenbergii) are found in tropical and sub-tropical regions. Generally, they are found in lakes, rivers and swampy areas with ...Missing: trophic | Show results with:trophic
[42]
optimum dietary protein requirement for macrobrachium rosenbergii ...
Five protein levels from 20 – 40% at 5% interval were tested to assess the best growth. Mean body weights and lengths of 4 replicate treatments were subjected ...
[43]
Diet containing 35% crude protein improves energy balance, growth ...
The diet containing 35% P is a good alternative to optimize the use of energy channeled toward growth and minimize energy loss via excretion.
[44]
Effect of dietary protein, lipid and carbohydrate ratio on growth ...
These results suggest that 35 % dietary protein and 10 % lipids and 20 % carbohydrates (L:C ratio 1:2) are optimal for growth performance and activity of ...
[45]
(PDF) Bioaccumulation of lead, mercury and nitrates of Macrobrachium rosenbergii (Shrimp) as indicator of water pollution in Iponan River, Cagayan de Oro
### Summary: Macrobrachium rosenbergii as a Bioindicator of Water Pollution in Iponan River
[46]
Marine shrimps as biomonitors of the Fundão (Brazil) mine dam ...
Jul 15, 2022 · Shrimps are recently described as bioindicators of water quality (Bertrand et al., 2018; Daam and Rico, 2018; Lavarías et al., 2011) and have ...
[47]
Freshwater Shrimp Effects on Detrital Processing and Nutrients in a ...
Aug 9, 2025 · In this paper, we report on a whole-pool manipulation of leaf litter decomposition in a tropical stream following a hurricane.
[48]
[PDF] Linking shrimp assemblages with rates of detrital processing along ...
Understanding the roles of species in ecosystem processes such as primary production, decomposition, and nutrient cy- cling can provide important insights ...
[49]
The giant Malaysian prawn, Macrobrachium rosenbergii, a potental ...
The giant Malaysian prawn, Macrobrachium rosenbergii, was found to prey upon two major South American species of schistosome vector snails.
[50]
How fat prawns can save lives | NSF - National Science Foundation
Jul 25, 2019 · As the prawns grow, they feed on the snails that carry the schistosome parasite, says Justin Remais of UC-Berkeley, senior author on the study.
[51]
[PDF] Effects of freshwater shrimp assemblages on benthic communities ...
In tropical island stream ecosystems freshwater shrimps are often the dominant macroconsumers and can play an important role in determining benthic community.
[52]
Responses of bacterial communities and organic matter degradation ...
Mar 10, 2021 · Highlights. Macrobrachium nipponense bioturbation could promote the organic matter degradation in sediment.
[53]
The culture potential and management problems of freshwater ...
They are also prey for fish, birds, and reptiles (). Macrobrachium prawns may spawn several times per year, and large species may produce ...
[54]
(PDF) Diet Survey and Trophic Position of Macrobrachium ...
Aug 7, 2025 · The feeding ecology and trophic level of this species in the Anzali Wetland, southwestern Caspian Sea, was investigated by both a traditional ...
[55]
Net-chasing training improves the size homogeneous of freshwater ...
Sep 15, 2023 · These findings indicate that net-chasing training suppressed the behavior of fighting and cannibalism, producing a homogeneous prawn size at high density.Missing: upon birds amphibians
[56]
Non-Native Decapods in South America: Risk Assessment and ...
Jul 9, 2023 · Procambarus clarkii is considered one of the most invasive crustacean species in the world, and its introduction outside its natural environment ...
[57]
[PDF] The invasive status of Macrobrachium rosenbergii (De Man, 1879) in ...
May 11, 2011 · Introduction of Macrobrachium rosenbergii to Brazil for prawn farming has resulted in escapes to the local natural environment. In.Missing: makros brachion
[58]
Effects of river control structures on the juvenile migration of ...
Aug 7, 2025 · Migratory species of Macrobrachium prawns are strongly affected by dams that block their reproductive behaviour by preventing the downstream ...
[59]
[PDF] Nearly 400 million people are at higher risk of schistosomiasis ...
One hypothesis that has received less attention argues that the Diama Dam excludes native, migratory snail predators, notably Macrobrachium spp. river prawns, ...
[60]
Effect of exposure to cadmium on the tropical freshwater prawn ...
The effect of cadmium (Cd) on mortality, resistance and bioaccumulation in the tropical freshwater prawn Macrobrachium rosenbergii from Egypt were studied.
[61]
Biological effects of glyphosate and emamectin benzoate based ...
Nov 12, 2024 · This study evaluates the acute and chronic effects of two commercial formulations EMACOT and SUNPHOSATE-G on juveniles of a prawn species (Macrobrachium ...
[62]
Geographical variation of the structure and population parameters of ...
Mar 11, 2023 · Macrobrachium species are the most fished and traded among the exploited freshwater prawns' species and constitute an important source of income ...
[63]
The impact of climate change on prawn postlarvae fishing in coastal ...
The study found that climate change has severe impacts on prawn postlarvae fishing. The catch of postlarvae on the Pasur River showed a sharply declined over ...
[64]
Global Status of Giant Prawn, <i>Macrobrachium rosenbergii</i ...
The global production of GP in 2021 was 3,13,756 t with a value of over $ 2.45 billion. China is the top producer with a production of 1,71,263 t accounting for ...
[65]
Giant river prawn - Cultured Aquatic Species
However, even if a very modest expansion of 10 percent/yr occurs, global farmed production of M. rosenbergii will have significantly exceeded 400 000 tonnes by ...Missing: 2020s | Show results with:2020s
[66]
chapter 4. hatchery phase
This new manual, which replaces an earlier manual first issued in 1982, is an up-to-date practical guide to the farming of Macrobrachium rosenbergii.
[67]
a targeted resource, the giant freshwater prawns "macrobrachium ...
This study provides information on the environment, modes of access and exploitation of Macrobrachium species, the level of capture, the operators and their ...
[68]
Culture of the Amazon River Prawn Macrobrachium Amazonicum
This crustacean is a crucial resource for the subsistence of many Amazon communities that depend economically on artisanal fishing [16]. The species also ...
[69]
Freshwater prawn farming in Brazilian Amazonia shows potential for ...
Oct 1, 2001 · Freshwater prawns (Macrobrachium spp.) are commonly harvested by artisanal fishermen and traditionally consumed by locals. The shrimp are very ...
[70]
[PDF] Characteristics and processing of canned Amazon River prawn ...
Jul 26, 2023 · Amazon River prawn (Macrobrachium amazonicum) in Amazon sauce. Brazilian Journal of Food Technology, 27, e2023092. https://doi.org/10.1590 ...
[71]
Indonesia Shrimp Market Size, Growth and Forecast Report 2030
A major trend in the Indonesian shrimp market is the rapid adoption of sustainable aquaculture practices, driven by both market demand and regulatory ...<|control11|><|separator|>
[72]
Navigating Nitrofuran Challenges in Farmed Prawn (Macrobrachium ...
Jul 7, 2025 · The industry's growth has been supported by favorable climatic conditions, extensive water bodies, and a skilled labor force in aquaculture ...
[73]
Phylogeny of Macrobrachium spp. (Decapoda, Pleocyemata) from ...
Jan 20, 2025 · Eight Macrobrachium species have been reported from the Peruvian Pacific slope, but their phylogenetic relationships are still unknown.phylogenetic Analyses · results · references
[74]
Scientific knowledge of the Cinnamon River prawn Macrobrachium ...
Aug 17, 2024 · M. acanthurus presents several characteristics that make it a suitable species for aquaculture, such as resistance to changes in environmental conditions.Missing: introduced | Show results with:introduced
[75]
https://zse.pensoft.net/article/154936/
[76]
Morphological and molecular characterization of freshwater prawn ...
Dec 8, 2019 · We investigated the morphological and molecular identification of freshwater prawns of the genus Macrobrachium in South, South West, and ...
[77]
Molecular perspective on the American transisthmian species of ...
Nov 25, 2014 · The high morphological similarity between some American species led Holthuis (1952) to designate Atlantic and Pacific Macrobrachium “sister ...Missing: challenges | Show results with:challenges
[78]
Farming freshwater prawns. A manual for the culture of the giant ...
This new manual, which replaces an earlier manual first issued in 1982, is an up-to-date practical guide to the farming of Macrobrachium rosenbergii.
[79]
https://zookeys.pensoft.net/article/4254/
[80]
Macrobrachium americanum (cauque river prawn)
The caque river prawn, Macrobrachium americanum, is a commercially important species in Mexico, Guatemala and El Salvador and a potential candidate for ...
[81]
[PDF] Experimental culture of the river prawn Macrobrachium americanum ...
ABSTRACT. The cauque river prawn Macrobrachium americanum occurs along the Pacific coast of. America. This prawn can grow to a large size, ...
[82]
Natural diet and feeding habits of a freshwater prawn ... - SciELO
Macrobrachium carcinus is a Brazilian native prawn with recognized potential for use in aquaculture activities. However, there is little information about ...
[83]
Macrobrachium carcinus, Bigclaw river shrimp - SeaLifeBase
Macrobrachium carcinus (Linnaeus, 1758). Bigclaw river shrimp. Native range | All suitable habitat | Point map ...Missing: original | Show results with:original
[84]
Population structure, mortality, and recruitment of Macrobrachium ...
Mar 24, 2017 · Macrobrachium amazonicum is extensively exploited in northern and northeastern Brazil (Lucena-Frédou et al., 2010; Lima et al., 2014), where it ...Materials And Methods · Results · Discussion<|control11|><|separator|>
[85]
[PDF] 94 - Distribution: Indo-West Pacific
Habitat: Fresh water; juvenile stages in brackish or salt water. Size: Maximum total length 181 mm. Interest to Fishery: Being a large sized shrimp, ...
[86]
[PDF] morphometric characterization and performance evaluation of
3). Macrobrachium latidactylus (scissor river prawn). This species is found mainly in estuarine and inshore marine waters. Adults are commonly found in tidal ...
[87]
Macrobrachium vollenhovenii (African river prawn)
M. vollenhovenii is an important local fishery product in many West African countries including Ivory Coast, Gabon, Guinea, Senegal, Zaire and Nigeria.Missing: vollenhoveni | Show results with:vollenhoveni
[88]
Aquaculture Environment Interactions 10:487
Nov 14, 2018 · Although the endemic African river prawn Macrobrachium vollenhovenii is a natural candidate for aquaculture and biocontrol, efforts to ...Missing: vollenhoveni | Show results with:vollenhoveni