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Lepisosteiformes
Lepisosteiformes
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Lepisosteiformes
Temporal range: Early Jurassic–present[1]
Florida gar (Lepisosteus platyrhynchus) (Lepisosteidae)
Fossil of Scheenstia maximus (Lepidotidae)
Scientific classification Edit this classification
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Clade: Ginglymodi
Order: Lepisosteiformes
Hay, 1929
Families

For other genera, see text

Lepisosteiformes is an order of ray-finned fish and the only living members of the clade Ginglymodi. Its only extant representatives are the gar (family Lepisosteidae), and it is defined as all members of Ginglymodi that are more closely related to gar than to the extinct Semionotiformes, the other major grouping of ginglymodians. They are one of two extant orders in the infraclass Holostei alongside the Amiiformes (now represented by only the bowfins).[2][1]

While represented only by the two extant genera of gar from North America, the Lepisosteiformes are an ancient group known as far back as the Early Jurassic, and formerly had a much larger range, being known from almost every continent. Considerable morphological diversity is known among extinct members compared to modern gar, from the superficially gar-like Obaichthyidae to the semionotiform-like Lepidotidae, which were previously classified in the Semionotiformes.[3][4]

Evolution

[edit]

The earliest known lepisosteiform is the marine Lepidotes from the Early Jurassic of Germany, which largely shares the original body plan of Ginglymodi shared with Semionotiformes.[1] However, phylogenetic estimates suggest that the earliest lepisosteiforms diverged from their closest relatives in the Middle Triassic. The most basal lepisosteiform is thought to be Khoratichthys from the Late Jurassic or Early Cretaceous of Thailand, which is thought to have diverged from other members of the group during the Late Triassic.[5] Other studies suggest that the most basal member is Neosemionotus from the Early Cretaceous of Argentina, which diverged from the rest of the group during the Early Jurassic.[6]

Numerous early lepisosteiforms (including basal lepisosteiforms such as Khoratichthys and Lanxangichthys, lepidotids such as Isanichthys, and basal lepisosteoids such as Thaiichthys) are known from the Late Jurassic and Early Cretaceous of Thailand and Laos, suggesting that what is now Southeast Asia may have been an important region for early lepisosteiform evolution, and that ginglymodians were the dominant fish in freshwater ecosystems in the region at the time.[5]

It has been suggested that as is with basal ginglymodians and the Semionotiformes, the earliest lepisosteiforms were marine and independently colonized and diversified in freshwater ecosystems multiple times; first among the Lepidotidae, and then among the Lepisosteoidei. Two independent freshwater colonizations appear to have occurred among the lepisosteioids: one in Southeast Asia and one in West Gondwana. The latter included the Obaichthyidae, close relatives of the gar.[6]

The ecology of the group including extinct members broader than that of living gars. Members of Lepidotidae in particular are strongly different from modern gars in having bulky bodies, with the large (up to 2 metres (6.6 ft)) lepidotid Scheenstia developing powerful jaws filled with rounded teeth that were likely used to crush shells (durophagy).[7]

Classification

[edit]

References

[edit]
Revisions and contributorsEdit on WikipediaRead on Wikipedia

Lepisosteiformes

View on Grokipedia
from Grokipedia
Lepisosteiformes is an order of primitive ray-finned fishes (class ) within the infraclass , commonly known as gars, distinguished by their elongated, tubular bodies covered in interlocking ganoid scales, long snouts filled with needle-like teeth, and a vascularized that enables aerial respiration in low-oxygen environments. This ancient lineage, with fossils dating back to the , represents one of the few surviving non-teleostean groups among the over 30,000 species of extant bony fishes, highlighting their evolutionary persistence as basal neopterygians. The order comprises a single extant family, Lepisosteidae, which includes seven living species divided between two genera: (alligator gars and tropical gars) and (true gars such as the and ). These predatory fishes range in size from about 1 meter to over 3 meters in length, with the largest species, the (Atractosteus spatula), capable of reaching weights up to 140 kg. Morphologically, gars feature a heterocercal tail, a positioned posteriorly, and 50–65 scales along the , adaptations suited to their ambush hunting style in shallow, vegetated waters. Gars are primarily distributed across freshwater systems of eastern North America—from southern Quebec and Montana in the north to Costa Rica in the south—along with isolated populations in Cuba, though some species tolerate brackish conditions and rarely enter marine environments. Ecologically, they inhabit slow-moving rivers, lakes, and swamps with abundant vegetation, where they prey on fish, crustaceans, and amphibians using their sharp dentition; their eggs are toxic to many predators, providing a unique defense mechanism among North American freshwater fishes. While extant diversity is low, the fossil record reveals a broader past distribution, including marine and South American habitats, underscoring the order's historical adaptability.

Description and Anatomy

Physical Characteristics

Lepisosteiformes, commonly known as gars, exhibit a distinctive elongate, tubular body shape adapted for predation in aquatic environments. These possess a heavily armored exterior, with the body covered in interlocking, rhomboid ganoid scales that consist of an enameled outer layer over a bony base, providing robust protection against predators and environmental hazards. The body length varies among species, but can reach up to 3 meters in the (Atractosteus spatula), one of the largest extant members of the order. The head is characterized by a long, beak-like snout that houses sharp, needle-like teeth arranged in one or more rows, designed for grasping and holding slippery prey such as fish. In species like the longnose gar (Lepisosteus osseus), the snout length is more than two-thirds of the total head length, enhancing their ability to strike sideways with precision. The jaws are elongate, with the jaw joint positioned anterior to the eye, supporting rapid snapping motions. Fins in Lepisosteiformes are positioned to optimize stability and propulsion during slow, stealthy movements. The is located posteriorly, often at 75-88% of the standard length from the , while the pectoral fins are set low on the body for maneuverability near the substrate. The is heterocercal, with the vertebral column extending into the upper lobe to provide during bursts for hunting, though externally it may appear nearly symmetrical in some species. Gars also possess a vascularized that enables facultative air breathing, supplementing respiration in low-oxygen conditions.

Sensory and Physiological Adaptations

Lepisosteiformes, commonly known as gars, possess a highly vascularized that functions as an accessory , enabling aerial respiration in oxygen-poor aquatic environments. This adaptation allows gars to gulp air at the water's surface, supplementing gill-based oxygen uptake when dissolved oxygen levels drop below critical thresholds, such as in warm, stagnant, or hypoxic waters typical of their habitats. The 's internal structure features extensive vascularization and partitions similar to those in lungs, facilitating efficient during periodic surfacing events. Complementing this aerial capability, gars exhibit reduced gill surface area compared to strictly water-breathing fish, which minimizes water flow over the gills and conserves oxygen acquired from air . In species like the ( osseus), this reduction is particularly pronounced at higher temperatures, where up to 70-80% of total oxygen intake derives from the rather than the gills, ensuring metabolic demands are met in low-oxygen conditions. This physiological trade-off enhances survival in seasonally hypoxic ecosystems but relies on the 's to prevent deficits. Sensory adaptations in Lepisosteiformes support their predation strategy in often turbid or vegetated waters. The system is well-developed, with neuromasts sensitive to low-frequency vibrations and water displacements generated by nearby prey movements, allowing detection and localization even in low-visibility conditions. This mechanosensory array runs along the body and head, providing hydrodynamic cues essential for orienting strikes toward evasive targets. Additionally, the eyes are positioned dorsally on the head, optimizing upward vision to monitor surface prey while the body remains concealed below, a configuration suited to their lurking behavior near the water column's interface. Osmoregulatory adaptations enable gars to tolerate brackish waters, expanding their range into estuarine and coastal zones. In species such as the (Atractosteus spatula), kidneys produce hypotonic urine to excrete excess water in freshwater while conserving salts, and gills actively transport ions via cells to maintain internal osmolality during salinity fluctuations up to 24 ppt. Larger individuals exhibit enhanced tolerance, with coastal populations showing comparable ionoregulatory efficiency to inland ones, involving upregulated Na+/K+-ATPase activity in both organs to counter osmotic stress without significant plasma ion disruptions.

Distribution and Habitat

Geographic Range

The current geographic range of Lepisosteiformes is restricted to freshwater and occasionally brackish systems in eastern , extending from southern and the southward through the basin and to , with an isolated population in . Seven extant species occur within this distribution, primarily in rivers, lakes, and swamps of the region. One notable endemic species, the Cuban gar (Atractosteus tristoechus), is confined to western , including the southwestern marshes and rivers as well as , representing the smallest natural distribution among living lepisosteiforms. Native populations are absent from the and Pacific regions following the Pleistocene, with rare occurrences in places like attributed to human introductions rather than natural persistence. Historically, the record of Lepisosteiformes reveals a much broader global distribution, with early appearances in the across multiple continents. This wide paleobiogeography contrasts with the modern relictual range, reflecting dispersal patterns involving multiple independent invasions of freshwater habitats from marine ancestors during the .

Environmental Preferences

Lepisosteiformes, commonly known as gars, exhibit a strong preference for shallow, slow-moving freshwater environments such as rivers, lakes, swamps, and backwaters, where dense aquatic and submerged structures like fallen logs provide essential cover and opportunities. These habitats are typically characterized by warm, stagnant or sluggish waters with muddy or sandy bottoms, allowing gars to thrive in lowland systems across their range. Gars demonstrate remarkable tolerance for low-oxygen conditions prevalent in these warm, stagnant waters, facilitated by their facultative air-breathing , which involves gulping atmospheric oxygen into a highly vascularized —a detailed further in discussions of sensory and physiological traits. While primarily freshwater inhabitants, certain species, such as the ( spatula), occasionally venture into brackish estuaries, exhibiting limited tolerance up to around 24 ppt, but they generally avoid fully marine or fast-flowing waters that exceed their physiological limits. Seasonal migrations are a key aspect of their reproductive , with adults moving into flooded areas during spring to spawn in shallow, vegetated inundations triggered by rising water levels, ensuring suitable conditions for egg adhesion and larval development. Microhabitat partitioning occurs across life stages, with adults favoring deeper channels and open river sections for foraging and resting, while juveniles preferentially occupy vegetated marginal shallows and backwaters, which offer protection from predators and abundant prey resources.

Evolutionary History

Origins and Fossil Record

The order Lepisosteiformes, comprising gars and their extinct relatives, has a fossil record extending back to the . The earliest known lepisosteiform is represented by species of the genus , documented from the stage (approximately 183 million years ago) in , where specimens preserve gastric contents indicative of a diet including crustaceans. These early forms exhibit a body plan largely consistent with the broader ginglymodian lineage, featuring ganoid scales and robust skeletal elements. Basal diversification of lepisosteiforms occurred during the to , with key evidence from . The genus Khoratichthys, from deposits dated to approximately 150–140 million years ago in Thailand's Phu Kradung Formation, represents one of the most primitive known members and supports the hypothesis of an early cradle of diversification in this region. This period marks the initial radiation within the order, transitioning from more generalized neopterygian morphologies toward specialized gar-like features. A significant radiation took place during the , exemplified by the Obaichthyidae family, which appeared in the – stages (approximately 125–95 million years ago) across , , and . Fossils from the Parnaíba Basin in and other Gondwanan sites highlight their widespread distribution prior to influences. A recent discovery includes the early diverging lepisosteid Britosteus amarildoi gen. et sp. nov. from the of , providing further insights into anatomical diversity during this radiation. The order's extinct diversity encompasses numerous described species, including durophagous specialists such as Scheenstia from the , which reached lengths up to 2 meters and possessed low, rounded crushing jaws adapted for hard-shelled prey. These forms illustrate morphological experimentation, from elongate predatory types to robust crushers, within the lepisosteiform clade. Following peak diversity in the , lepisosteiforms experienced a decline after the Eocene, with reduced representation in post-Paleogene deposits outside . Modern genera, such as and , first appear in the fossil record during the , signaling the emergence of extant lineages amid ongoing faunal turnover. This timeline underscores the order's ancient origins within , with fossils providing a chronological framework for its evolutionary conservatism.

Phylogenetic Relationships

Lepisosteiformes represents the sole extant clade within the larger group , which also encompasses various extinct lineages such as Semionotiformes, positioned as the to Lepisosteiformes based on cladistic analyses of skeletal morphology and molecular . Within the broader , Lepisosteiformes is the to (represented by the , Amia calva), forming a monophyletic assemblage that contrasts with earlier hypotheses favoring a closer affinity between Amiiformes and Teleostei (the Halecostomi hypothesis). This positioning of as the sister taxon to the diverse Teleostei constitutes the crown , a subdivision of the basal ray-finned fishes (), highlighting Lepisosteiformes as a key lineage retaining plesiomorphic traits amid the of more derived teleosts. Key synapomorphies uniting , including Lepisosteiformes, include modifications to the preopercle, where a sensory canal runs along its margin, facilitating enhanced mechanosensory detection, and a reduction in the number of branchiostegal rays to typically three or four, compared to the greater count in more basal actinopterygians. These features, detailed in comprehensive osteological studies, underscore the shared evolutionary of gars and bowfins, with Lepisosteiformes further distinguished by retention of primitive characteristics such as ganoid scales—rhomboid, enamel-covered structures providing robust armor absent in most teleosts. Such traits position Lepisosteiformes as a "" lineage, bridging ancient neopterygian forms and modern fish diversity. Molecular evidence, particularly from the genome assembly, strongly supports the deep divergence of from Teleostei around 300 million years ago during the period, predating the teleost-specific whole-genome duplication event that fueled their . Phylogenomic analyses using gene-order conservation and chromosomal synteny confirm this timeline, with exhibiting slower evolutionary rates and fewer gene duplications relative to teleosts, consistent with fossil-calibrated molecular clocks estimating the crown at approximately 328 million years ago. This ancient split aligns with paleontological evidence of early neopterygian diversification, though detailed fossil timelines are addressed elsewhere.

Classification and Diversity

Taxonomic Structure

Lepisosteiformes is an order of ray-finned fishes () classified within the infraclass of the subclass , though the of has been debated in some phylogenetic analyses that position it as part of the broader . The order represents the only extant lineage of , a group that originated in the and encompasses both living and extinct forms characterized by elongate bodies, ganoid scales, and predatory adaptations. The taxonomic structure of Lepisosteiformes includes a single extant family, Lepisosteidae (gars), which comprises two genera: (encompassing New World needle-nosed gars such as the ) and (including alligator gars with broader snouts, like the ). This family is monophyletic, as confirmed by a 2017 phylogenetic analysis using molecular and morphological data from nearly 2,000 species, which provided 100% bootstrap support for its unity within the order. Extinct lineages within Lepisosteiformes are more diverse, with the fossil record spanning from the to the Pleistocene and including at least one well-established family, Obaichthyidae (spiny gars), known from deposits in and and featuring genera such as Obaichthys and Dentilepisosteus. Broader extinct taxa associated with lepisosteoid fishes number approximately 10 families and over 60 genera, reflecting significant diversity before a decline in the . These extinct groups, such as those in Obaichthyidae, exhibit morphological variations like more robust spines compared to modern forms, highlighting the evolutionary conservatism of the order.

Extant Species

The order Lepisosteiformes encompasses seven extant within the Lepisosteidae, commonly known as gars, all of which are piscivores characterized by elongated bodies, ganoid scales, and specialized snouts that vary in length and shape to facilitate prey capture in diverse aquatic environments. These exhibit a relict distribution primarily in freshwater systems of North and , with one endemic to , reflecting their ancient lineage with limited diversification compared to other actinopterygian groups. The (Lepisosteus osseus) is the most widespread species, occurring across eastern from the and southward through the basin to the Gulf Coast and into northeastern , inhabiting rivers, lakes, and brackish estuaries. It features a notably slender, elongated comprising over two-thirds of its head length, which aids in ambushing in open water, and can reach up to 2 meters in total length with a maximum weight of approximately 23 kg. The (Lepisosteus oculatus) is distributed in the central and , from the drainages southward to the Gulf Slope in and , preferring quiet pools, backwaters, and vegetated swamps. Distinguished by its profuse dark spots covering the body, head, and fins, it typically attains lengths of 0.8 to 1.2 meters and weighs up to 4.4 kg, with the spotted pattern providing among submerged vegetation. Inhabiting the basin from southern to and extending to the Gulf Coast, the (Lepisosteus platostomus) occupies sluggish lowland streams, lakes, and floodplains, often near emergent vegetation. Its blunt, short —less than half the head —sets it apart, adapting it for feeding in shallow, weedy areas, with adults rarely exceeding 1 meter in and 2.6 kg in weight. Restricted to the , particularly peninsular and coastal rivers from Georgia to the Ocklockonee River, the Florida gar (Lepisosteus platyrhincus) thrives in slow-moving, vegetated waters of lowland streams and lakes. It possesses a broad, short and numerous dark spots on the anterior body and head, reaching a maximum of 1.32 meters and 9.6 kg, with the wider jaws facilitating capture of prey in confined spaces. The (Atractosteus spatula), native to the from the basin to the and northeastern , is the largest extant species, inhabiting large rivers, reservoirs, and brackish bays. Its massive, broad head and short, paddle-like snout resemble an alligator's, enabling powerful strikes on large ; it can grow to 3 meters long and over 137 kg, making it a in its range. Found in across and Pacific drainages from southern to , the (Atractosteus tropicus) frequents warm, stagnant backwaters, slow rivers, and seasonal lakes, often appearing as floating logs on the surface. Similar in form to the but smaller, it has a broad and reaches about 1.25 meters in length and 2.9 kg, preying primarily on in tropical lowland habitats. Endemic to western and , the Cuban gar (Atractosteus tristoechus) inhabits rivers, lakes, and brackish coastal areas, closely resembling the in morphology with a broad suited for piscivory. It attains up to 2 meters in length, but populations have declined severely due to habitat loss and , classifying it as critically endangered.

Biology and Ecology

Reproduction and Development

Lepisosteiformes, commonly known as gars, exhibit seasonal spawning behaviors primarily occurring in spring from April to June in shallow, vegetated s when water temperatures rise to 20–25°C. This timing aligns with floodplain inundation, providing suitable nursery habitats for deposition and early development. Reproduction involves , where males and females broadcast gametes over submerged vegetation or debris. The eggs are adhesive, allowing them to attach to substrates, and contain ichthyootoxin, a potent substance toxic to many vertebrates and but harmless to gars themselves. Clutch sizes vary by and size, typically ranging from 10,000 to 150,000 eggs per female; for example, females average around 138,000 eggs. Eggs hatch in 5–8 days at approximately 25°C, with incubation periods shortening at higher temperatures, as observed in where hatching occurs around 6 days at 17–20°C. Gars provide no following spawning, leaving eggs and larvae vulnerable to environmental conditions. Upon , larvae possess an adhesive organ on their , enabling them to remain attached to vegetation while absorbing their for initial nourishment, typically lasting several days until they reach about 19 mm in length. During early development, larvae initially feed on small planktonic organisms before shifting to a more carnivorous diet of and small within weeks, marking the transition to active foraging. Sexual maturity is generally reached at 3–5 years for most Lepisosteiformes species, though it varies; for instance, mature around 3 years, while females may take 5–11 years. Females are typically larger and longer-lived than males, with females capable of exceeding 50 years in age.

Diet and Predatory Behavior

Members of the order Lepisosteiformes, commonly known as gars, are primarily piscivorous predators, with adults consuming a variety of such as minnows, shad, and other species. These are typically captured through tactics, where the gar remains stationary amid or cover before executing a rapid lateral strike with its elongated beak to seize prey. Once impaled on the gar's needle-like teeth, which interlock to prevent escape, the prey is maneuvered headfirst and swallowed whole. This feeding strategy exploits the gar's specialized morphology, which facilitates precise alignment and capture during strikes. Juvenile gars exhibit a transitional diet beginning around 10-11 days post-hatching, initially focusing on including larvae, cladocerans, copepods, and other small crustaceans before shifting to small as they grow. This early piscivory supports rapid growth, with young gars employing similar ambush techniques but targeting smaller, more accessible prey near the water's surface or in shallow habitats. Across species, such as the (Lepisosteus osseus) and (Lepisosteus oculatus), juveniles show high reliance on even at small sizes, with shiners and minnows comprising the bulk of their intake. Feeding patterns in Lepisosteiformes display opportunistic and seasonal variations, with dominating the diet in warmer months when forage abundance peaks, while like crustaceans may supplement intake during cooler periods of reduced activity. For instance, in (Atractosteus spatula), gizzard shad remain a staple across seasons, but prey selection adjusts to local availability, including occasional amphibians or terrestrial during floods. As apex predators, gars play a key trophic role in regulating populations of smaller , thereby maintaining balance, and they occasionally scavenge dead prey when opportunities arise. Species like the shortnose gar (Lepisosteus platostomus) further partition resources by incorporating more and alongside , reducing overlap with congeners.

Social and Behavioral Patterns

Members of the order Lepisosteiformes, commonly known as gars, exhibit predominantly solitary behaviors throughout much of their life cycle, with individuals maintaining discrete home ranges and showing limited social interactions outside of specific environmental or reproductive contexts. Young gars lead solitary lives, independently in shallow, vegetated habitats, while adults reinforce this isolation by defending personal territories, particularly in structured riverine or environments where co-occurrence with conspecifics is minimal unless resource-driven. Loose aggregations may form transiently during spawning events without establishing lasting social bonds. Gars are facultative air-breathers, relying on a highly vascularized to supplement respiration, which enables survival in hypoxic environments but manifests in observable surface-oriented behaviors. In warm, stagnant water with low dissolved oxygen, adults periodically gulp air at the surface, with frequency increasing under hypoxic stress to maintain oxygen uptake—often observed as regular surfacing every few minutes during activity or environmental duress. This air-breathing mechanism, briefly referenced here, supports their tolerance of deoxygenated conditions common in summer backwaters. Defensive responses in gars include dramatic leaping out of the water when startled or pursued to evade threats or dislodge hooks during encounters. Territoriality is pronounced among adults, especially males during breeding periods, where they exhibit heightened to guard spawning sites or personal foraging areas, though inter-individual conflicts remain minimal outside these contexts. Activity patterns in Lepisosteiformes are primarily diurnal, with gars actively patrolling shallow waters for opportunities during daylight hours and retreating to vegetated cover for nocturnal to avoid predation or conserve energy. In colder months, individuals migrate to deeper, more stable waters to overwinter, reducing movement and metabolic demands in response to seasonal declines.

Conservation and Human Interactions

Current Status and Threats

Most species within Lepisosteiformes are assessed as Least Concern on the IUCN Red List, including the longnose gar (Lepisosteus osseus) and spotted gar (Lepisosteus oculatus), reflecting their relatively stable global populations despite localized pressures. However, the alligator gar (Atractosteus spatula) is classified as Vulnerable by the American Fisheries Society due to population declines exceeding 50% over three generations in portions of its range, driven by historical overexploitation and habitat alterations. The Cuban gar (Atractosteus tristoechus) faces the most severe risk, listed as Critically Endangered on the IUCN Red List owing to an estimated 90% population reduction across its limited Cuban range. Primary threats to Lepisosteiformes include habitat loss from dam construction, channelization, and wetland drainage, which fragment floodplains and eliminate vegetated spawning grounds essential for . exacerbates declines, particularly through targeting large individuals and incidental in commercial fisheries, reducing mature breeding stocks. from agricultural runoff and industrial effluents further impairs , inducing physiological stress and of contaminants in tissues. In altered river systems, pose additional risks through competition for resources. Natural hybridization among native species can also lead to genetic in sympatric populations. Local extirpations highlight vulnerability; the was historically considered extirpated from the , though recent captures, such as one in April 2025, suggest ongoing presence or recovery. Population trends vary regionally: core habitats in the basin support stable numbers, with estimates exceeding 8,000 individuals in managed reservoirs, but populations remain fragmented and declining in peripheral or modified watersheds. As of 2025, reintroduction efforts continue in , with stocking in the Cache River.

Management and Protection

Management and protection of Lepisosteiformes species, particularly (Atractosteus spatula), involve a combination of regulatory measures, restoration initiatives, and research efforts across their range in . In , anglers are permitted a daily bag limit of one of any size, with mandatory reporting of all harvests within 24 hours to monitor population impacts; additionally, a special drawing allows selected participants to harvest one over 48 inches from the River to manage trophy populations sustainably. In contrast, imposes a statewide ban on harvest to support ongoing restoration, recognizing their role in . Similarly, enforces a no-harvest period from noon May 1 to noon July 1 to protect spawning, with a daily limit of one under 36 inches and required tags for larger individuals, promoting population stability. Restoration programs emphasize stocking and habitat enhancement to bolster declining populations. The U.S. Fish and Wildlife Service (USFWS), through facilities like the Private John Allen National Fish Hatchery, propagates and stocks fingerlings in the Valley to restore historical abundances, focusing on areas with suitable habitats. Habitat rehabilitation efforts prioritize reconnection, which facilitates spring flooding essential for gar spawning and juvenile rearing; projects in the basin have demonstrated improved recruitment by restoring natural hydrologic connectivity. In , spawn conservation closures implemented since 2007 have contributed to population recovery by reducing exploitation during critical reproductive periods, allowing for increased natural recruitment. Several species benefit from inclusion in protected areas and targeted research. (Lepisosteus oculatus) inhabit National Preserve in , where federal regulations limit harvest and provide consumption advisories to safeguard populations within this . Genetic studies on the Cuban gar (Atractosteus tristoechus) have revealed critically low diversity, guiding to prevent inbreeding and support reintroduction efforts in . initiatives for , including volitional spawning protocols for captive-reared individuals, aim to produce stock for supplementation while reducing wild harvest pressure, as outlined in conservation aquaculture frameworks.

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