Dune Habitats Research Articles

Determining the impacts of conservation fencing on woma pythons (Aspidites ramsayi)

Context Fenced conservation reserves are an effective management tool for the conservation of many threatened species. However, conservation fencing is known to inadvertently affect non-target species, ranging from barrier effects to direct mortality. There is a paucity of information on the negative impacts of fencing on reptiles. Aims Using the woma python, a species of conservation significance, this research aimed to improve our knowledge of how reptiles interact with fences. Methods The spatial ecology of womas was explored in relation to fencing at the Wild Deserts project partnership site, a rabbit-, cat- and fox-proof fenced area of Sturt National Park in arid Australia. A 6-year dataset of opportunistic observations of womas at the study site were analysed for demographic, spatial and temporal patterns in woma fence interactions. Nine adult pythons were radiotracked over a year to assess space use in relation to fencing. Key results Twenty-two per cent of all opportunistic woma observations at the site were mortalities associated with entanglements. All 20 entanglement deaths were in 30-mm netting despite 50-mm netting comprising lower segments of 21% of the fence network. Fencing encounters were greatest in dune habitats and during summer and autumn. Fence crossings were infrequent among telemetered pythons and most encounters did not result in entanglement, with four of the nine individuals recorded to have crossed the fence successfully, despite one mortality. Conclusions Thirty-millimetre netting, particularly in areas of netting overlap, represents an entanglement risk to womas. Implications This research is applicable to the management of conservation fences and can be extended to other large snake and reptile species. The impacts of small-aperture netting on large snakes and other non-target species should be considered in the planning phases for conservation fencing and mitigation strategies should be sought in the planning phases where possible. Large-aperture netting is preferable to 30-mm netting for pythons, where exclusion of rabbits is not necessary. However, larger netting apertures may disproportionately affect other non-target species such as bearded dragons.

Inversions contribute disproportionately to parallel genomic divergence in dune sunflowers.

The probability of parallel genetic evolution is a function of the strength of selection and constraints imposed by genetic architecture. Inversions capture locally adapted alleles and suppress recombination between them, which limits the range of adaptive responses. In addition, the combined phenotypic effect of alleles within inversions is likely to be greater than that of individual alleles; this should further increase the contributions of inversions to parallel evolution. We tested the hypothesis that inversions contribute disproportionately to parallel genetic evolution in independent dune ecotypes of Helianthus petiolaris. We analysed habitat data and identified variables underlying parallel habitat shifts. Genotype-environment association analyses of these variables indicated parallel responses of inversions to shared selective pressures. We also confirmed larger seed size across the dunes and performed quantitative trait locus mapping with multiple crosses. Quantitative trait loci shared between locations fell into inversions more than expected by chance. We used whole-genome sequencing data to identify selective sweeps in the dune ecotypes and found that the majority of shared swept regions were found within inversions. Phylogenetic analyses of shared regions indicated that within inversions, the same allele typically was found in the dune habitat at both sites. These results confirm predictions that inversions drive parallel divergence in the dune ecotypes.

The Okuru skink (Oligosoma carinacauda sp. nov) of South Westland, New Zealand-simply elusive or extinct?

A small brown, longitudinally striped skink from Okuru, South Westland, New Zealand is described as Oligosoma carinacauda sp. nov. It is distinguished from all congeners by the combination of three supraocular scales and a keeled tail. The species is known only from a single specimen, collected from sphagnum moss within supralittoral dune habitat at Mussel Point, Okuru in 2000. Follow-up targeted surveys undertaken since by expert herpetologists have failed to relocate the species to date. As it is known that many New Zealand lizard species face a perilously uncertain future due to anthropogenic-induced pressures such as habitat loss, predatory pests, and climate change, there are serious concerns for the survival of this species.

High ecostoichiometric stability and accumulating SiO2 and NO3− as main physiological adaptive mechanisms for reed to adverse environments

Previous studies have shown that nutrients accumulation played important roles in resisting to stress resistance of plants. Our study examined the ecostoichiometric internal stability (EIS) of nutrients accumulation and, concomitantly identified the main resistant regulating substances and their contributions to stress resistance of reed (Gramineae) in arid desert areas. Plants (digging method) and soil samples (quartering method)) obtained from sand dune (SD), desert steppe (DP), interdune lowland (IL), saline meadow (SM) and wetland (W) habitats were brought back to the lab for nutrients analysis. Results indicated that soil nutrients differed obviously, while reed maintained relatively stable ratios of SiO2:N, N:K, and P:K when the eco-environments changed in different habitats. Furthermore, reed exhibits common adaptive characteristics by mainly accumulating large amounts of SiO2 (122.6–174.0 g/kg) and NO3− (166.1–216.6 g/kg), as well as moderate levels of soluble sugar (SS: 24.0–55.0 g/kg), which are mainly stored in leaves for stress resistance. The contribution of ions to stress resistance was 80.03%–91.15% (with SiO2 and NO3− accounting for 54.91%–63.10%), whereas the contribution of solutes was only 8.85%–19.97% (with SS contributing to 5.14%–10.91%) in different habitats. These findings suggest that maintaining relatively high EIS, while still accumulating SiO2 and NO3− as main physiological regulators might be an effective strategy for reed to positively respond to adverse habitats, which provide a strong theoretical basis and technical reference for searching useful methods for restoration and reconstruction of the degraded ecosystems in desert oasis regions.

Dune Hares: Population Indices, Home Range Size, and Habitat Selection of the European Hare on a Danish Island.

Population indices, such as transect counts of animals, can provide important information concerning population changes over time. Moreover, data concerning the home range size and habitat selection of individuals can provide valuable insight into spatial requirements of animals and how they can adapt to variable environments. Here, we describe the population development of European hares (Lepus europaeus) and investigated home range sizes and habitat selection of six radio-tagged individuals on the small (80 ha) Danish Wadden Sea island Langli. The average minimum hare population density from 1983 to 1997 was 64 ± 36 (mean ± SD) hares/km2, with hare numbers varying among years and seasons. The average home range size was 23.3 (CI: 18.9-28.7) ha, which is comparable to agricultural areas of high structural diversity. Moreover, hare habitat selection was generally bimodal, with hares moving over larger areas and selecting marsh habitat for foraging during nighttime, and dune and grassland habitat for resting during daytime, especially during winter. Combined, our results indicate that hare abundance and space use in the dunal landscape of Langli Island were similar to agricultural areas of comparatively high habitat quality. Thus, dunal marsh landscapes offer high-quality habitat for hares and might be of importance as population strongholds at a time when hare populations are declining in many agricultural areas across Europe.

Patterns of island fox habitat use in sand dune habitat on San Clemente Island

On San Clemente Island (SCI), the island fox subspecies Urocyon littoralis clementae has been monitored annually since 1988 to track long‐term population trends. Annual density estimates in most habitat types across the island range from 2 to 13 foxes/km2, yet unusually high estimates have repeatedly approached 50 foxes/km2 in a unique sand dune habitat area. Although sand dune habitat is restricted to one small area on the island, these estimates suggest sand dune habitat supports one of the highest population densities of any fox species in the world, and it may support > 5% of the SCI fox population. This finding prompted our investigation to determine if SCI foxes captured in the sand dunes habitat area maintained home ranges within this habitat type. Between January and July 2018, we used global positioning system (GPS) collars to track the movements of 12 island foxes captured in the sand dune habitat area. Contrary to our initial predictions, we found that island foxes captured in the sand dune habitat area do maintain home ranges and core areas centralized in sand dune habitat. All 12 island fox home ranges estimated contained > 50% sand dune habitat in either their 50% or 95% fixed kernel density estimate (KDE) home range, and island foxes were 3.14 times more likely to use active sand dune habitat when compared to the second most abundant habitat type, maritime desert scrub (Adjusted β = 3.14, 95% CI = 3.07–3.12). We also found that island foxes in sand dune habitat maintained much smaller home ranges than reported estimates in other habitat types, with an average 95% KDE home range size of 0.42 km2 (95% CI = 0.20–0.63 km2). Although sand dune habitat comprises just 2% of available habitat on SCI, our research highlights the importance of this unique habitat area for island foxes.

Seasonal and Diel Gopher Tortoise (Gopherus polyphemus) Activity and Burrow Use by Commensals in Coastal Beach Dune Habitat as Examined by Wildlife Cameras

Seasonal and Diel Gopher Tortoise (Gopherus polyphemus) Activity and Burrow Use by Commensals in Coastal Beach Dune Habitat as Examined by Wildlife Cameras

Spatial Variation in Flowering Age in <i>Cirsium pitcheri</i>: Does This Imperiled Dune Thistle Hedge Its Bets?

For perennial plants, the optimal timing of flowering is a tradeoff between survivorship and fecundity, a classic example of bet-hedging. For many monocarpic perennials, there is an advantage in delaying flowering until the plant reaches a larger size and is thus capable of a higher fecundity. However, in delaying flowering, there is a risk that the plant will die before ever reproducing. Here, we investigate this fitness trade-off in the imperiled dune thistle, Cirsium pitcheri (Torr. ex Eaton) Torr. & A. Gray (Asteraceae) (Pitcher’s thistle). Using a long-term, spatially explicit demographic data set with yearly censuses, we found that C. pitcheri individuals on the foredune flowered at a younger age compared to individuals in other dune habitats. We tested two alternative hypotheses: (1) younger flowering plants were able to reach a flowering threshold size more quickly, and (2) these plants were somehow stressed, and slow growth was a signal for high likelihood of dying, resulting in early reproduction at a smaller size. Our results support the former hypothesis: plants in all areas of the dune did not differ in size the year prior to flowering, despite spatial differences in age of flowering individuals. Therefore we conclude that the foredune microenvironment where plants flowered at younger ages facilitates rapid growth and reproduction for this species and may represent optimal habitat. This result provides insight into the demographic patterns of C. pitcheri that may inform the conservation and recovery of this threatened species. Although adapted to the dynamic dune environments of the Great Lakes, C. pitcheri may be vulnerable to climate change-induced changes in its optimal foredune habitat.

Dune restoration must consider species that need open and early successional dune habitats.

Dune restoration must consider species that need open and early successional dune habitats.

Drivers of dune formation control ecosystem function and response to disturbance in a barrier island system.

Barrier islands are landscape features that protect coastlines by reducing wave energy and erosion. Quantifying vegetation-topographic interactions between adjacent habitats are essential for predicting long-term island response and resilience to sea-level rise and disturbance. To understand the effects of dune dynamics on adjacent interior island ecosystem processes, we quantified how sediment availability and previous disturbance regime interact with vegetation to influence dune building and ease of seawater and sediment movement into the island interior on two US mid-Atlantic coast barrier islands. We conducted field surveys of sediment accretion, vegetative cover, and soil characteristics in dune and swale habitats. Digital elevation models provided assessment of water flow resistance from the mean high water mark into the island interior. We found that geographic location impacted sediment accretion rates and Panicum amarum (a species increasing in abundance over time in the Virginia barrier islands) accreted sediment at a significantly lower rate compared to other dune grasses. Dune elevation impacted the ease of seawater flow into the island interior, altering soil chlorides, annual net primary productivity, and soil carbon and nitrogen. Our work demonstrates the importance of incorporating biological processes and cross-island connectivity into future scenario modeling and predictions of rising sea-levels and increased disturbance.

Flooding, season and habitat interact to drive changes in vertebrate scavenging and carcass persistence rates

Scavenging dynamics are influenced by many abiotic and biotic factors, but there is little knowledge of how scavengers respond to extreme weather events. As carrion is a major driver of the organisation and structure of food webs within ecological communities, understanding the response of scavengers to extreme weather events is critical in a world that is increasingly subject to climate change. In this study, vertebrate scavenging and carcass persistence rates were quantified in the Simpson Desert of central Australia; a system that experiences major fluctuations and extremes in weather conditions. Specifically, a total of 80 adult red kangaroo (Osphranter rufus) carcasses were placed on the landscape and monitored using remote sensor cameras. This included 40 carcasses monitored before and then 40 carcasses monitored after a major flooding event. The carcasses were monitored equally before and after the flood across different seasons (warm and cool) and in dune and interdune habitats. Overall, a total of 8124 scavenging events for 97,976 visitation minutes were recorded for 11 vertebrate species within 30 days of carcass placement pre- and post-flood. Vertebrate scavenging increased post-flood in the warm season, especially by corvids which quadrupled their scavenging events during this time. There was little difference in carcass persistence between habitats, but carcasses persisted 5.3-fold longer post-flood in warm seasons despite increased vertebrate scavenging. The results demonstrate that a flood event can influence scavenging dynamics and suggest a need to further understand how seasons, habitats and extreme weather events can drive changes in carrion-based food webs.

Implementing a vegetation-based risk index to support management actions in Mediterranean coastal dunes

Coastal dunes play a crucial role in mitigating sea-related impacts and safeguarding coastlines. However, increasing human influence and natural factors such as sea-level rise underscore the need for effective coastal risk assessment methodologies. This study introduces a comprehensive coastal risk index covering 24 km of the Italian coastline within the protected area of San Rossore Park (Tuscany, Italy). The study area, distinguished by its notable coastal dune ecosystems, holds naturalistic, cultural, and economic importance. Nevertheless, diverse uses, zoning, and human impact variables pose challenges.By incorporating geological, socioeconomic, cultural, and ecological parameters, the index integrates a range of data sources and field observations. This research focused on developing and applying a vegetation-based risk index (VRI) within a geographic information system (GIS) framework, recognizing the ecological importance of dune vegetation in mitigating coastal erosion. Analysisrevealed varying risk levels within the study area. Half of the San Rossore Park coastline exhibited low risk values, 37.5% had moderate risk values, and 12.5% had high risk values. The publicly accessible northernmost section displays excellent preservation of dune habitats but faces heightened risk due to anthropogenic impacts. Conversely, the central-southern portion, inaccessible to the public, registers high-risk levels linked to variables associated with coastal erosion.Furthermore, the results highlight areas with heightened cultural and ecological vulnerabilities aligned with elevated risk levels. The index facilitates clear and intuitive cartographic representations of coastal risk, identifying variable categories that substantially influence on risk determination. Tailored strategies, including mitigating human pressure in the northern sector and implementing erosion management in the central-southern region, are recommended.In summary, this study not only provides a practical tool for assessing and managing coastal areas and directing attention to specific threats but also supports stakeholders in informed decision-making. The VRI enhances global sustainable coastal conservation, deepening our understanding of coastal risks and providing valuable insights for effective management strategies.

The spider fauna of Danish coastal dune habitats revisited after 25 years: evidence of faunistic impoverishment

Arthropod faunas have become impoverished in recent years in abundance as well as in diversity, but so far little evidence exists concerning spiders. In 2022, we repeated pitfall trap collections of spider assemblages completed 25 years previously in coastal dune habitats of the Hanstholm Reserve of National Park Thy, Denmark. Traps were placed approximately at the same spots, i.e. the habitats (white dune, grey dune, dry dune heathland, wet dune heathland, low pine plantation) were represented approximately as before. Contrary to most previous reports of insect decline, we found only weak evidence of reduction in abundance, but strong indications of reductions in faunistic value based on changes in ecological traits. Within the same period of spring and with the same number of traps, we collected 12% fewer spider individuals and 13% fewer species; rarefaction indicated that the lowered species richness was real. Species diversity had decreased and dominance increased. Changes in indices of ecological traits showed that the fauna had changed into decreased contribution of habitat specialists and species of restricted Danish distribution; the proportion of aeronauts had increased; the average body size had decreased. Indices of assemblage microclimatic niche positions and niche widths showed increased representation of shade and humidity loving species. Most of these changes were repeated in each of the habitats. Finally, we found evidence of a phenological shift towards activity earlier in spring in some species.Implications for insect conservationWe discuss possible management measures to counteract the observed trend towards reduced faunistic value.

Occupancy and detectability of a critically threatened lizard endemic from sandy coastal plains areas of Rio de Janeiro State, Brazil

AbstractLiolaemus lutzae is a small liolaemid lizard critically endangered and restricted to coastal restinga (salty sand dune habitats covered by herbaceous and shrubby vegetation by seaside) habitats of the state of Rio de Janeiro in Brazil. This lizard has been predicted to be extinct by 2080. We studied some of the environmental factors that influence occupancy by the species and detectability by the observer, in addition to investigating which populations remain occupying the areas along its original geographical distribution. We sampled 25 different beach habitats of restinga areas in the state, by 100‐meter replicates of linear transects. The estimated probability of occupancy was 69% (0.69 ± 0.05), and the estimated detectability was 50% (0.50 ± 0.03). The detection model with the best fit contained only the air temperature variable. Occupancy was best described by four variables: number of disturbance sources on the transect, vegetation cover in a 50‐meter buffer, exposed sand cover substrate in a 20‐meter buffer, and built‐up area cover in a 50‐meter buffer. No observations of L. lutzae were made in eight of the 25 restinga areas sampled along the original distribution of the lizard. In seven of these areas, the species had its populations extirpated many years ago, based on the 2007/2008 monitoring data. Conversely, in one area where the species was frequently observed during field surveys and different ecological studies on the species made in last decade, it was not recorded in the present study, indicating a possible recent population extirpation. We recommend that conservation measures be urgently implemented to mitigate anthropogenic impacts on the areas of the remaining populations of this lizard throughout its range, especially preserving the structure and functions of the remaining vegetation of beach habitat along restinga areas.

Tylopilus dunensis (Boletaceae, Basidiomycota): notes on morphological, phylogenetical and distributional aspects

Tylopilus is a worldwide distributed genus of boletes with about 100 known taxa, of which at least 16 are fromBrazil and Guyana. Tylopilus dunensis, a species originally described from sand dune habitats in the state of Rio Grande doNorte in northeastern Brazil, has now been recovered in a ‘tabuleiro’ (i.e., tableland forest) from Paraíba. The main pheneticfeatures of this still poorly known species are the orange to orange-ochraceous pileus with yellowish brown margins, unchangingpileus context, the pale cream hymenophore with wide pores, the yellowish stipe, the small and narrow basidiospores, andthe long and frequent dextrinoid pseudocystidioid pleurocystidia. After the discovery of the phylloporoid tube trama in ourspecimens, we emended tube trama type of T. dunensis.

Modeled Sea Level Rise Impacts on Coastal Vegetation and Infrastructure at Lake Earl Wildlife Area and Tolowa Lagoon, Northern California: Implications for Management and Adaptive Planning

Few ecosystems remain untouched by sea-level rise along the Pacific coast of North America. This process has facilitated reduction in the range of ecosystem responses and promoted loss of biological diversity at a scale relevant to local populations of plants and animals. Even fewer studies have evaluated the extent of rising sea levels on coastal ecosystems at finer scales. Here, I quantified the projected impacts of rising sea level on the vulnerability of plant communities at the Lake Earl-Tolowa Lagoon System (Lake Earl Wildlife Area) using a Static Vegetation Model. I also evaluated use of a recent regional coastal Marsh-migration Model fitted to the same study area. Results showed the Static Model predicted 100% of Estuarine Brackish Emergent habitat, 34.0% of Coastal Dune habitat, 80.7% of Freshwater Emergent Wetland, 48.9% of Forest Wetland, 21.0% of Grassland/Pasture, 8.0% of Coastal Maritime Forest, and 3.4% of Urban infrastructure would be inundated by salt-water at ~3.0m (~9.8 ft) of sea-level rise. Conversely, categories of marsh-types used in the Marsh-migration Model were inconsistent with the type of vegetation mapped within the study area, and impacts to these categories did not materialize until ~14 m (~45.9 ft) of sea-level rise. At this level Estuarian Wetland, Emergent Wetland, and Unconsolidated Shore exhibited slight increases in area, while other categories declined. The Marsh-migration Model also proved insufficient at identifying any major alteration in the extent of marsh-types for future planning or conservation by land managers, which was the primary goal of this model at conception. Identifying the potential impact of future sea-level rise on biological communities necessitates extensive data collection, quantification of plant and animal communities, updating existing vegetation maps, modeling the potential for migration inland, and establishing a comprehensive, multi-scale coastal-change modeling framework at spatiotemporal scales unique to the particular wildlife area. These actions are necessary to identify, assess, mitigate, and alleviate any potential future stressors in rising sea-level on natural resources on managed lands along the coast of northern California and elsewhere.

The vegetation of Holocene coastal dunes of the Cape south coast, South Africa.

The vegetation of calcareous coastal dunes of Holocene age along the south coast of South Africa's Cape Floristic Region is poorly described. This vegetation comprises a mosaic of communities associated with two biomes, Fynbos and Subtropical Thicket. Previously, expert knowledge rather than quantitative floristic analysis has been used to identify and delimit vegetation units. In many areas, mapped units conflate vegetation on Holocene sand with that on unconsolidated sediments of late Pleistocene age, despite pronounced species turnover across this edaphic boundary. Despite dominance by Cape lineages and fynbos vegetation, dune vegetation in the eastern part of the region has been included in the Subtropical Thicket Biome rather than the Fynbos Biome. The high levels of local plant endemism associated with this dune vegetation and the small and fragmented configuration of these habitats, makes it an urgent conservation priority especially when placed in the context of rising sea levels, increasing development pressures and numerous other threats. Here we provide a quantitative analysis of 253 plots of the 620 km2 of Holocene dune vegetation of the study area using phytosociological and multivariate methods. We identified six fynbos and two thicket communities based on the occurrences of 500 species. Following a long tradition in Cape vegetation typology, we used the Strandveld (beach vegetation) concept as our first-order vegetation entity and identified six units based on the fynbos floras. These were, from east to west, Southeastern Strandveld, St Francis Strandveld, Goukamma Strandveld, Southwestern Strandveld and Grootbos Strandveld. Each unit was differentiated by a suite of differential species, most being Holocene dune endemics. The two thicket communities-Mesic and Xeric Dune Thicket-showed limited variation across the study area and were subsumed into the Strandveld units. We discussed our findings in terms of vegetation-sediment relationships, emphasizing the need for a greater geographical coverage of sediment ages to facilitate a better understanding of deposition history on vegetation composition. We also discussed the role of soil moisture and fire regime on structuring the relative abundance of fynbos and thicket across the Holocene dune landscape. Finally, we address the conservation implications of our study, arguing that all remaining Holocene dune habitat should be afforded the highest conservation priority in regional land-use planning processes.

Ants and Restingas: the Relationship Between the Geometric Model, Vegetation Cover, and Myrmecofauna in a Dune Habitat in Bahia, Brazil

In this study, we propose to investigate whether the geometric model and vegetation cover of restinga remnants influences the diversity of ants on the Northern Coast of Bahia. Using Winkler extractors and baits of honey and sardines, the ants were collected from five restinga remnants. Correlations were made between the percentage of soil with vegetation cover, circularity and fractal dimension index and the diversity and richness of ants. Lastly, Kendall correlations and Theil-Kendall regression were performed. The diversity index of ants was not associated with the percentage of soil with vegetation cover. The diversity and richness of terrestrial ants were negatively influenced by the circularity index and positively by the fractal dimension index. The circularity index was inversely proportional, while the fractal dimension index was equivalent to the ant diversity index. The similarity dendrogram showed that areas with less fragmentation had similar myrmecofauna composition. The vegetation cover of the soil does not influence the diversity of ants, but the fragmentation of the areas and the geometric model measured by the fractal dimension index have an influence, being possible that the type of soil, in general, prevents the nesting of a larger volume of species and mask the possibility of finding a closer relationship between these variables.

Formal analyses are fundamental for the definition of honey, a product representing specific territories and their changes: the case of North Tyrrhenian dunes (Italy)

Honey is a variegate matrix depending significantly on the floral origin, and it could become an important agri-food product to valorise specific territories. Being so diverse, different analytical techniques are necessary for its description. Herein we characterized the honey produced in one of the Italian sand dunes systems hosting beekeeping activities. In terms of floristic origin, phytochemical characterization, and sensory and colour analysis, honey collected in 2021 and 2022 was comparable. Honey was polyfloral, with several pollens from dune habitat plants classified as minor. The presence of the allochthonous Amorpha fruticosa L. and the ruderal Rubus fruticosus L. pollens in the category of the secondary pollens testifies the alteration of the park vegetation. The phytochemical profile was rich in polyphenols. Other interesting compounds were coumarine derivatives, likely attributable to resin-laden plants as rockroses, long chain hydroxyacids typical of royal jelly and nicotinic acid and its analogues (2-hydroxynicotinic acid and 2-hydroxyquinoline). The above-mentioned honey showed interesting features and was a good representation of the vegetation of this area. Our study pointed out the importance of relying on multiple analytical techniques for the characterization of honey and the advisability of a technical support toward beekeepers to correctly describe and valorise their product.

Comparative morpho-anatomical study on Leptadenia pyrotechnica (Apocynaceae) growing in the hyper-arid and arid habitats of Saudi Arabia.

The use of wild plants is considered to be an eco-friendly and promising natural resource. In sandy desert habitats, Leptadenia pyrotechnica flourishes as a xerophytic shrub with high biomass production. As a dominant shrub in the arid sand dune habitats of Saudi Arabia, Leptadenia pyrotechnica (Forssk.) Decne (Asclepiadaceae) is one of the most common xerophytes; the many medicinal uses of this plant include treating allergies, productive coughs, abortions, diabetes, stomach disorders, fevers, kidney disorders, and stones. In such a distribution, morpho-anatomical characteristics, among other adaptive traits, play an important role. This study aims to characterize some morpho-anatomical adaptations of L. pyrotechnica in two stressful habitats: the hyper-arid inland sand dunes of the Empty Quarter (EQ) and the arid coastal sand dunes of Jazan. A morpho-anatomical analysis of plant stems and roots from both habitats was conducted using light microscopy (LM) and scanning electron microscopy (SEM). The outcomes indicated similar characteristics, a low surface-to-volume ratio (S/V), a thin boundary layer (δbl), an epidermis with many layers of hypodermis, bundles of sclerenchymatous cells around vascular tissue, and storage starch grains in ray parenchyma between xylem conduits. On the other hand, the L. pyrotechnica stem from the hyper-arid habitat of the Empty Quarter revealed more encrypted stomata, more elongated palisade cells, less calcium oxalate crystals with low Ca percentage, and a high vulnerability index of xylem vessels compared with the same traits of the stem from the Jazan coastal sand dunes habitat. Roots of L. pyrotechnica from both habitats revealed similar features of general anatomy. However, differences in specific anatomical traits were observed, especially in xylem vessel characters. The vulnerability index of root xylem vessels from the Empty Quarter habitat was more than that from the Jazan coastal sand dunes habitat. Furthermore, vestured bordered pits in root xylem walls were more abundant in the Empty Quarter habitat than in the Jazan coastal sand dunes habitat. As a result, these characteristics in the morpho-anatomy of L. pyrotechnica from both habitats provide practical adaptations to highly stressful conditions, along with specific anatomical traits relating to each habitat.