Rare Species Research Articles

A machine learning approach for protected species bycatch estimation

IntroductionMonitoring bycatch of protected species is a fisheries management priority. In practice, protected species bycatch is difficult to precisely or accurately estimate with commonly used ratio estimators or parametric, linear model-based methods. Machine-learning algorithms have been proposed as means of overcoming some of the analytical hurdles in estimating protected species bycatch.MethodsUsing 17 years of set-specific bycatch data derived from 100% observer coverage of the Hawaii shallow-set longline fishery and 25 aligned environmental predictors, we evaluated a new approach for protected species bycatch estimation using Ensemble Random Forests (ERFs). We tested the ability of ERFs to predict interactions with five protected species with varying levels of bycatch in the fishery and methods for correcting these predictions using Type I and Type II error rates from the training data. We also assessed the amount of training data needed to inform a ERF approach by mimicking the sequential addition of new data in each subsequent fishing year.ResultsWe showed that ERF bycatch estimation was most effective for species with greater than 2% interaction rates and error correction improved bycatch estimates for all species but introduced a tendency to regress estimates towards mean rates in the training data. Training data needs differed among species but those above 2% interaction rates required 7-12 years of bycatch data.DiscussionOur machine learning approach can improve bycatch estimates for rare species but comparisons are needed to other approaches to assess which methods perform best for hyperrare species.

Effects of Landscape Heterogeneity and Disperser Movement on Seed Dispersal

The primacy of endozoochory for the maintenance and expansion of many woody plant populations is well known, but seed dispersal is not well understood for most species. This is especially true for rare species, where small population size and low fruit production can limit field- or observation-based experiments. Additionally, the effect of environmental heterogeneity on disperser movement is rarely investigated but has been shown to improve estimates of plant population spatial patterns and dynamics. We used simulation experiments to explore the effects of environmental heterogeneity and disperser movement on Lindera subcoriacea seed dispersal, a rare shrub from the southeastern United States with avian-dispersed seeds. Our experiments incorporated environmental heterogeneity and simulated disperser movement for five bird species, based on either landscape permeability or straight path rules. We anticipated that permeability-based movement would result in greater dispersal distances and seed dispersal effectiveness, which characterizes both quantity and quality. Generally, we did not find differences in seed dispersal between permeability and straight path experiments. However, we did find that permeability-based experiments had greater deposition into suitable habitat during flight (23 vs. 1%). These rare but longer distance depositions may be especially important for plants that are influenced by gap or interpopulation dynamics. We also found consistently greater dispersal into high quality habitats regardless of disperser species in permeability experiments, implying that incorporating species-specific assessments of landscape utilization (occupancy) could influence the effectiveness of seed dispersal. Our study suggests that including environmental heterogeneity in seed dispersal models can provide additional insights not provided by avian parameters (e.g., gut capacity, seed retention time, and flight speed) commonly used to inform dispersal models.

Current progress and future prospects for understanding genetic diversity of seed plants in China

AbstractGenetic diversity represents the fundamental basis of biological variation within species, and is therefore the ultimate representation of biodiversity. Despite that all forms of diversity being defined by genomic differences, genetic diversity has received relatively less attention compared with species and ecosystem diversity. Here, we review recent literature and conclude that progress in understanding genetic diversity of seed plants, is strongly associated with advances in sequencing technology. We here present case studies to illustrate the application of genetic diversity for tracing crop domestication and delimiting species boundaries. Understanding genetic diversity is particularly critical for the field of conservation biology, and there is a clear shift to population‐level genetic studies to understand rare species. We then document additional factors that potentially influence genetic diversity, including climate change, habitat fragmentation, and species invasion. Finally, we identify current research limitations and propose directions for future studies. We highlight the need to develop broad‐scale genetic diversity knowledge, combined with other aspects of diversity to improve biodiversity conservation outcomes. We conclude that populating global databases with genomic‐scale sequence data for all species is an urgent and achievable goal now.

Wildlife fencing at German highways and federal roads – requirements and management implications

In Germany, the high risk of wildlife–vehicle collisions (WVC) is further increasing due to increasing traffic volumes and road densities as well as the growing population densities of common ungulate species. As a result, threats to human health and property as well as wildlife mortality of widely spread and rare species increase. Currently, three basic types of wildlife fences are used in Germany: type A, a conventional galvanized‐high tensile deer fence (made of knot braid); type B, a chain wire (mesh wire) fence; type C, a rigid welded wire mesh fence panels. Since fencing needs to restrict access of many different species with different behaviours (e.g. jumping, climbing, digging), fencing needs to be multifaceted to be effectively. Furthermore, the occurrence of wildlife species with habits such as jumping, climbing or digging determines the optimal (functional) fence design per location. We surveyed road managers in combination with a personal assessment of road sections in Germany and derived the following recommendations for optimal fencing to reduce WVC: 1) To deter digging, use plates made of recycled synthetic materials or a concrete foundation, instead of barbed wire. 2) Fencing should be made of chain wire (mesh wire, type B) fence or rigid welded wire mesh fence panels (type C) instead of knot braid mesh (type A). 3) To restrict climbing, use angled chain wire fence or rigid welded wire mesh fence panels at the top of the fences. 4) Maintain fences so that they are kept free from ingrown vegetation/woods. Maintenance conditions should be considered while planning and building the fence, especially to ensure sufficient space on both sides for accessibility. 5) Fencing should be established preferably near the roadside and moved away from property lines. In conclusion, wildlife fencing could be a very effective mitigation measure to prevent WVC with common as well as protected species, when proper designed and recommendations of the survey will be consequently considered. Currently many wildlife fences lack functionality due to an inappropriate design and maintenance issues in Germany.

Chromosome-level genome assembly and characterization of the Calophaca sinica genome.

Calophaca sinica is a rare plant endemic to northern China which belongs to the Fabaceae family and possesses rich nutritional value. To support the preservation of the genetic resources of this plant, we have successfully generated a high-quality genome of C. sinica (1.06 Gb). Notably, transposable elements (TEs) constituted ~73% of the genome, with long terminal repeat retrotransposons (LTR-RTs) dominating this group of elements (~54% of the genome). The average intron length of the C. sinica genome was noticeably longer than what has been observed for closely-related species. The expansion of LTR-RTs and elongated introns emerged had the largest influence on the enlarged genome size of C. sinica in comparison to other Fabaceae species. The proliferation of TEs could be explained by certain modes of gene duplication, namely, whole genome duplication (WGD) and dispersed duplication (DSD). Gene family expansion, which was found to enhance genes associated with metabolism, genetic maintenance, and environmental stress resistance, was a result of transposed duplicated genes (TRD) and WGD. The presented genomic analysis sheds light on the genetic architecture of C. sinica, as well as provides a starting point for future evolutionary biology, ecology, and functional genomics studies centered around C. sinica and closely-related species.

Smuggling “in the new way” or analysis of the latest legislative changes

The article examines the changes made to the CC by the Law of Ukraine “On Amendments to the Criminal Code of Ukraine and the Criminal Procedure Code of Ukraine regarding the criminalization of smuggling of goods and excise goods, as well as false declaration of goods” dated 09.12.2023 № 3513-IX. It not only brought back criminal responsibility for smuggling of goods as an independent component of the crime, also made several other changes to Chapter VII of the Special Part of the CC. The purpose of this article is to analyze the legislative amendments regarding the recriminalization of smuggling of goods, excise goods and to develop a proposal for further improvement of the provisions of Art. 201, 201-1, 201-3 and 201-4 of the CC.
 The analysis of the novels made it possible to establish that, on the one hand, the recriminalization of the smuggling of goods is a rather successful decision of the legislator, since for a long time it was an urgent need that both scientists and practitioners talked about. On the other hand, the adoption of Law № 3513-IX, first of all, violated the system of norms located in Chapter VII of the Special Part of the CC. It seems that in Art. 201 of the CC should establish criminal liability for smuggling of goods, while in Art. 201-1 of the CC should provide for criminal liability for the smuggling of goods that have specific conditions for their export/import (excise goods, timber or lumber of valuable and rare tree species, unprocessed timber), as well as items that are prohibited to be exported from Ukraine (cultural values, other timber that is prohibited for export outside the customs territory of Ukraine). Provisions on the smuggling of other items should be fixed in Chapter IX or XIII of the Special Part of the CC of Ukraine. It is not possible to agree with the minimum amount of contraband goods established by the legislator, which is related to their total value. The sanction for smuggling goods is subject to criticism, as it does not take into account the requirements of Part 2 of Article 53 of the CC. There is also a question regarding the final punishment in cases of smuggling of goods and other items provided for in Art. 201, 201-1 and 201-4 of the CC. It is also appropriate to exclude points 1 and 2 of the footnote to Art. 201 of the CC, which provides definitions of methods of committing the smuggling of any items.

The greater the proportion of Robinia pseudoacacia in a stand the greater its effect on the population characteristics of Erythronium dens-canis

Management of invasive alien plants is an increasing problem throughout the world. In some cases native rare or protected species can appear or even prefer habitats dominated by invasive alien plants, which raises questions about the optimal treatment of such areas. Erythronium dens-canis in Hungary is a protected species which only have several occurrences in the country and a number of these populations situated in Robinia pseudoacacia stands developed after harvesting native forests. In this study a total of five populations of E. dens-canis were surveyed between 2020 and 2022 in southwestern Hungary examining and comparing the ongoing demographic changes under native and Robinia stands by monitoring individual plants. Two populations were situated in forests composed of native tree species, two in Robinia pseudoacacia-dominated stands and one in a Robinia-native tree species mixed stand. We categorized the plants into five age-state categories: dormant, seedling, juvenile, vegetative adult, and reproductive adult. We found some considerable differences (e.g. leaf size, reproduction rate) between the populations situated in native and in Robinia stands, whereas the population in mixed forest showed intermediate character in most examined factors. Based on our results, R. pseudoacacia have a significant effect on the phenology and life history of E. dens-canis, and this effect is greater with higher proportion of R. pseudoacacia in a forest stand where the E. dens-canis occurs.

An Announced Extinction: The Impacts of Mining on the Persistence of Arthrocereus glaziovii, a Microendemic Species of Campos Rupestres

The mountaintops of eastern Brazil harbor the highest rates of plant endemism in South America. However, local biodiversity faces constant threats due to habitat loss and mining activities. About 89 rare and endangered species are exclusive to this region, including the threatened species Arthrocereus glaziovii. This study aims to evaluate the potential distribution of A. glaziovii based on abiotic variables and soil elements and to characterize the distribution of mineral titles that may restrict the species’ occurrence areas. We used the Bioclim, Domain, MaxEnt, GLM, and Random Forest algorithms to model this ecological niche under future climatic scenarios, in addition to modeling the layers of mineral titles corresponding to areas already mined and those slated for future mining projects. Our predictions indicate an expansion in the future distribution of A. glaziovii. Nevertheless, the future predicted occurrence areas of the species are already compromised due to mining. According to our findings, we emphasize the looming threat of the predicted extinction of this species. Therefore, implementing conservation strategies to ensure the survival of A. glaziovii is imperative.

New descriptions of the larval and pupal stages of Orthocladiusnitidoscutellatus and Psectrocladiusnevalis from Xizang, China (Diptera, Chironomidae).

Tibetan Plateau is one of the most typical areas of biodiversity in the world because of its unique environmental and regional units, which breed unique biological communities and concentrate on many unique and rare wild animals and plants. Research on Chironomidae in the Tibetan Plateau is relatively weak. At present, the identification of Chironomidae species mainly depends on male adults, while identification of larvae and pupae is relatively difficult and there is less research on them. During the investigations of insect diversity in the Tibetan Plateau, larval and pupal stages of Orthocladiusnitidoscutellatus Lundström, 1915 and Psectrocladiusnevalis Akhrorov, 1977 were described and illustrated. Matching and identification of larval and pupal stages were based on DNA barcodes. Neighbour-joining trees were reconstructed, based on known Orthocladius and Psectrocladius COI DNA barcodes, respectively.

Early detection of rare and elusive endangered species using environmental DNA: a case study for the Eurasian otter and the white-clawed crayfish in northwestern Italy

AbstractMonitoring, management and conservation of rare and elusive species often requires early detection of individuals, especially for re-introduced and endangered taxa. Environmental DNA (eDNA) approaches can enhance the detection power of traditional biomonitoring methods for low-density, newly-established populations. In this study, we used species-specific Real Time PCR TaqMan assays to assess the presence of two endangered freshwater species, the white-clawed crayfish Austropotamobius pallipes and the Eurasian otter Lutra lutra at eight sites in four river catchments in Liguria (northwestern Italy). The Eurasian otter was considered extinct in the study area since the 1980s. However, recent, although scattered sightings indicated a recolonisation by a few individuals. The white-clawed crayfish populations declined drastically and became increasingly dispersed in the western part of Liguria. Our eDNA analysis confirmed the presence of both species in some of the selected rivers and detected Eurasian otter DNA where the species was not recorded through traditional monitoring methods. This study confirms eDNA-based monitoring approaches as valuable tools to assess the presence of rare and elusive species and help implement protection plans at a local scale.

Biobanks as a way to conserve biodiversity in the context of the continuing decline in the species diversity of wild flora and fauna

To date, human actions have significantly changed 75% of the Earth's surface. This has resulted in an unprecedented increase in the rate of biodiversity loss in human history. According to the International Union for Conservation of Nature and Natural Resources, over the past 500 years, as a result of direct or indirect influence of the anthropogenic factor, 774 animal species and 123 plant species have become extinct. To prevent further loss of biodiversity, in the context of the ongoing «crisis of biodiversity», all over the world, including Kazakhstan, there is a need for reliable conservation of the available genetic resources of plants and animals, primarily rare and endangered species. In this regard, specialized biobanks of organized collections of living biomaterials are successfully used worldwide for the conservation and restoration of populations of rare and endangered species of flora and fauna. The article presents information about some of the largest biobanks and their importance in solving this global problem. The experience of scientific centers of Kazakhstan in the field of biobanking of biomaterials of wild flora and fauna, including rare and endangered species, is given, and the results of the National Center for Biotechnology in this area are summarized.

The neoteny goldilocks zone: The evolution of neoteny in Ambystoma.

Neoteny is a developmental strategy wherein an organism reaches sexual maturity without associated adult characteristics. In salamanders, neoteny takes the form of individuals retaining aquatic larval characteristics such as external gills upon maturation. Mole salamanders (Ambystoma) occupy a wide range of habitats and areas across the North American continent, and display examples of non-neotenic, facultatively neotenic and obligate neotenic species, providing high variation for investigating the factors influencing the evolution of neoteny. Here, we use phylogenetic comparative methods to test existing hypotheses that neoteny is associated with elevational and latitudinal distribution, cave-associated isolation, and hybridisation-related polyploidy. We also test if neoteny influences the diversity of habitats a species can occupy, since the restriction to an aquatic life should constrain the availability of different niches. We find that neoteny tends to occur in a narrow latitudinal band between 20-30° North, with particularly narrow latitudinal ranges for obligate compared to facultative neotenic species (16-52° North). We also find that facultatively neotenic species occur at elevations more than twice as high as other species on average, and that species with a higher frequency of neoteny typically have lower habitat diversity. Our results suggest that evolutionary transitions between non-neotenic and facultative neoteny states occur at relatively high and approximately equal rates. Moreover, we estimate that obligate neoteny cannot evolve directly from non-neotenic species (and vice versa), such that facultative neoteny acts as an evolutionary 'stepping stone' to and from obligate neoteny. However, our transition rate estimates suggest that obligate neoteny is lost >4-times faster than it evolves, partly explaining the rarity of obligate species. These results support the hypothesis that low latitudes favour the evolution of neoteny, presumably linked to more stable (aquatic) environments due to reduced seasonality, but once evolved it may constrain the diversity of habitats.

Management implications of habitat selection by whooping cranes (Grus americana) on the Texas coast

AbstractEffective habitat management for rare and endangered species requires a thorough understanding of their specific habitat requirements. Although machine learning models have been increasingly used in the analyses of habitat use by wildlife, the primary focus of these models has been on generating spatial predictions. In this study, we used machine learning models in combination with simulated management actions to guide planning and inform managers. We used data from 61 whooping cranes (Grus americana) tagged with GPS telemetry collars between 2009 and 2018 near Aransas National Wildlife Refuge in coastal Texas. We included variables based on topography, land use classification, vegetation height, plant phenology, drought, storm surge events, and both wild and prescribed fires. We then built models at multiple scales: population level, home range level, and roosting and daytime within home range level. We simulated responses to the two primary management actions used to enhance whooping crane habitat on Aransas National Wildlife Refuge: prescribed fire and removal of woody vegetation. At the population and home range scales, land use classification variables had the highest importance values, whereas the combined elevation and bathymetry layer was the most important predictor at both roosting and daytime within home range scales. Our findings revealed that the effects of fire, although generally modest, varied spatially. Areas dominated by estuarine wetlands exhibited higher predicted use within the first months after a fire, whereas those dominated by palustrine wetlands were more likely to be avoided in the immediate postfire years. Our simulation of vegetation removal identified the areas on Aransas National Wildlife Refuge where whooping cranes were predicted to benefit the most if vegetation were removed. These techniques can be used by other researchers wanting to examine and predict the effects of potential management actions on target species habitat.

Reclassifying the Threat Categories of Two Rare Plant Species Endemic to Central Anatolia

Aethionema turcica and Astragalus beypazaricus are rare endemic plant species restricted to marly-gypsaceous soils from Ankara, Turkey. In a study in 2000, Ae.turcica and A.beypazaricus were classified under the “Least Concern” and “Critically Endangered” threat categories, respectively. This study aimed to reassess the global conservation status of these species according to the IUCN Red List Categories and Criteria by using the recent findings based on their population sizes, distribution areas, and the main threats. Field research was conducted between 2016 and 2018. Additionally, physical-chemical soil tests were run, and the climatic data were utilized to draw bioclimatic conclusions. In Ankara, there are two populations of Ae.turcica, with 359 mature individuals covering 12 km2 AOO and 23.5 km2 EOO areas. A.beypazaricus has only one fragmented population with a total of 5700 mature individuals in Beypazarı, and both AOO and EOO were discovered to be 4 km2. Both species are on the verge of extinction due to habitat fragmentation and loss formed by intense anthropogenic activity. According to the findings, the IUCN threat categories for Ae.turcica and A.beypazaricus were suggested to be reclassified as CR based on the criteria B1ab(ii, iii) and B1ab(ii, iii)+2ab(ii, iii), respectively.

Modeling habitat suitability for the lesser-known populations of endangered mountain nyala (Tragelaphus buxtoni) in the Arsi and Ahmar Mountains, Ethiopia.

Habitat suitability models have become a valuable tool for wildlife conservation and management, and are frequently used to better understand the range and habitat requirements of rare and endangered species. In this study, we employed two habitat suitability modeling techniques, namely Boosted Regression Tree (BRT) and Maximum Entropy (Maxent) models, to identify potential suitable habitats for the endangered mountain nyala (Tragelaphus buxtoni) and environmental factors affecting its distribution in the Arsi and Ahmar Mountains of Ethiopia. Presence points, used to develop our habitat suitability models, were recorded from fecal pellet counts (n = 130) encountered along 196 randomly established transects in 2015 and 2016. Predictor variables used in our models included major landcover types, Normalized Difference Vegetation Index (NDVI), greenness and wetness tasseled cap vegetation indices, elevation, and slope. Area Under the Curve model evaluations for BRT and Maxent were 0.96 and 0.95, respectively, demonstrating high performance. Both models were then ensembled into a single binary output highlighting an area of agreement. Our results suggest that 1864 km2 (9.1%) of the 20,567 km2 study area is suitable habitat for the mountain nyala with land cover types, elevation, NDVI, and slope of the terrain being the most important variables for both models. Our results highlight the extent to which habitat loss and fragmentation have disconnected mountain nyala subpopulations. Our models demonstrate the importance of further protecting suitable habitats for mountain nyala to ensure the species' conservation.

Genomic divergence and mutational load in the Begonia masoniana complex from limestone karsts

Understanding genome-wide diversity, inbreeding, and the burden of accumulated deleterious mutations in small and isolated populations is essential for predicting and enhancing population persistence and resilience. However, these effects are rarely studied in limestone karst plants. Here, we re-sequenced the nuclear genomes of 62 individuals of the Begonia masoniana complex (B. liuyanii, B. longgangensis, B. masoniana and B. variegata) and investigated genomic divergence and genetic load for these four species. Our analyses revealed four distinct clusters corresponding to each species within the complex. Notably, there was only limited admixture between B. liuyanii and B. longgangensis occurring in overlapping geographic regions. All species experienced historical bottlenecks during the Pleistocene, which were likely caused by glacial climate fluctuations. We detected an asymmetric historical gene flow between group pairs within this timeframe, highlighting a distinctive pattern of interspecific divergence attributable to karst geographic isolation. We found that isolated populations of B. masoniana have limited gene flow, the smallest recent population size, the highest inbreeding coefficients, and the greatest accumulation of recessive deleterious mutations. These findings underscore the urgency to prioritize conservation efforts for these isolated population. This study is among the first to disentangle the genetic differentiation and specific demographic history of karst Begonia plants at the whole-genome level, shedding light on the potential risks associated with the accumulation of deleterious mutations over generations of inbreeding. Moreover, our findings may facilitate conservation planning by providing critical baseline genetic data and a better understanding of the historical events that have shaped current population structure of rare and endangered karst plants.

Butterfly fauna of Dhansiri Reserve Forest, Karbi Anglong, Assam, India

The field survey carried out to document the baseline data of butterfly fauna Dhansiri Reserve Forest of Karbi Anglong District, Assam recorded 106 species belonging to six families. Graphium sarpedon, Appias albina, Spindasis lohita, Charaxes marmax, Athyma ranga, Tanaecia lepidae, Hypolycaena othona and Euploea mulciber are legally protected species under the Indian Wild Life (Protection) Amendment Act, 2022. Eurema andersonii, Appias albina, Appias galba, Charaxes marmax and Athyma ranga are some of the rare species recorded during the study. Record of rare and endemic species from this Reserve Forest, and presence of species legally protected under the Indian Wildlife (Protection) Amendment Act, marks its importance as an area for butterfly conservation.

DISTRIBUTION AND POTENTIAL OF <i>CAMELLIA</i> SPP. IN THE CENTRAL HIGHLANDS, VIETNAM, FOR DEVELOPING HIGH-VALUE PRODUCTS IN THE FOOD INDUSTRY

This article focuses on the potential use of yellow camellias in the food technology industry by analyzing and synthesizing information from previous publications. Many rare species of the genus Camellia have been discovered recently in the Central Highlands of Vietnam, including 10 new species discovered in Lam Dong Province between 2012 and 2016. These 10 species account for 55.55% of the 18 species growing naturally in the Central Highlands and demonstrate the diversity of Camellia in the region. The flowers range from light yellow to orange to deep yellow in color. The survival rate of cuttings is 72.24%–83.33%, and the rooting rate when seeds are sown approaches 100%. Yellow camellias do not contain caffeine. The main active ingredient is polyphenol, with a content of 5.22%–30.11% (mg GAE/100 g DW). Camellia extract does not cause acute toxicity and has a blood sugar-lowering effect. Vietnam has much experience growing green tea; the total green tea growing area is 131,200 hectares. The average annual yield is 6.90 tons of fresh leaves per hectare, and the current export market to 60 countries is the basis for expanding the yellow camellia growing area. The Central Highlands has great potential as a stable source of raw materials to create fermented beverages, tea powder, tea oil, and colorants.

Free-living mites (Acari) of the Shokalsky Island, off the northern Gyda Peninsula, Kara Sea, High Arctic

The fauna of free-living mites of the Shokalsky Island, off the Gyda Peninsula, Kara Sea, totals at least 81 species belonging to 36 families. The suborder Prostigmata includes 38 species, vs 18 of Oribatida, 17 of Mesostigmata, 5 of Endeostigmata, and 3 of Astigmata. The most species-rich families are Ascidae (9 species), Eupodidae (7), Tarsonemidae (4), and Ceratozetidae (4). However, most genera (77%) are represented by one species only. Among mites identified to the species level, the Holarctic species prevail which show mainly arctic, arctic-montane, and arctic-boreal distribution patterns. The abundance of soil mites varies with 10160–299440 ind./m<sup>2</sup>, being the maximum in the soil of both dryad tundra and in a polar fox den on a hillock. Prostigmata are the most diverse mite group throughout, but the dominant species include either prostigmatic or endeostigmatic, or oribatid mites. The rare species, Charadracarus hurdi Newell, 1960, hitherto known only from Point Barrow, Alaska, has been found for the first time since its original description. Some features of the acarofauna of the Shokalsky Island are transitional between those characteristics of the polar desert and tundra zones.

Combination of thidiazuron and basal media type on optimizing in vitro growth of Grammatophyllum stapeliiflorum orchids

Grammatophyllum stapeliiflorum, recognized as the melancholic orchid, represents one of the elusive orchid species facing the brink of extinction, thus exacerbating its rarity. Tissue culture technology becomes imperative for the propagation of this orchid species. This study aims to scrutinize the influence of different concentrations of the synthetic growth regulator thidiazuron (TDZ) on distinct basal media types, Murashige Skoog (MS) and Vacin and Went (VW), on the in vitro growth of G. stapeliiflorum orchids. Employing a complete randomized factorial design, the study entails two research factors: TDZ concentration with 4 treatment levels, A0 = 0 mg/L, A1 = 0.25 mg/L, A2 = 0.50 mg/L, and A3 = 0.75 mg/L, and the second factor being the media type, B1 = ½ MS and B2 = ½ VW. Findings indicate significant effects of MS and VW media on the percentage of viable explants, browning, globular forms, and shoots. Interaction between TDZ concentration and media type didn't yield significant effects on each experimental parameter. Treatment with 0.25 and 0.50 mg/L TDZ on ½ VW media demonstrated optimal results for explant growth percentage, browning, and explants in the globular phase, at 97.33%, 2.67%, and 2.67%, respectively. Moreover, treatment with 0.75 mg/L TDZ on ½ VW media resulted in the highest percentage of explant coloration. The combination of TDZ and media has shown the potential to enhance the production efficiency and conservation of this rare orchid species through tissue culture technology.