Mitochondrial COI Gene Research Articles

Taxonomic notes on the genus Baetiella Uéno, 1931 (Ephemeroptera, Baetidae), with description of three new species from Thailand.

Based on material recently collected in northern Thailand, the present study provides an updated of the genus Baetiella, including Gratia. It comprises six species in Thailand, three of them being new species: Baetiella (Gratia) narumonae, Baetiella (Gratia) sororculaenadinae, Baetiella (Baetiella) bispinosa, Baetiella (Baetiella) baeisp. nov., Baetiella (Baetiella) lannaensissp. nov. and Baetiella (Baetiella) bibranchiasp. nov.Baetiella (Baetiella) baeisp. nov. can be distinguished from other species by the reduction of the posteromedian protuberances on abdominal tergites I-III, the asymmetrical coniform terminal segment of labial palp, the distal margin of abdominal sternites VII-X each with a row of long, spatulate setae, the dorsal margin of femur with two long, robust setae distally. Baetiella (Baetiella) lannaensissp. nov. is diagnosed by the posteromedian protuberances present on tergites I-VIII, dorsal margin of femur with a regular row of long, rounded, ciliated setae and body surface covered with numerous, dense, rounded scale-like setae. Baetiella (Baetiella) bibranchiasp. nov. can be separated from other species by coxal gills present at the base of forelegs and midlegs. The molecular study based on the mitochondrial gene COI and a larval key to species of Thai Baetiella are also provided.

DETERMINATION OF ENTOMOPATHOGENIC NEMATODE FAUNA IN ŞIRNAK, TURKIYE

This study focuses on the isolation, identification, and characterization of entomopathogenic nematodes (EPNs) in Şırnak Province, Turkey. Between July and September 2023, we collected 256 soil samples, from which 11 EPN isolates were successfully recovered,representing a 4.3% of the samples. These isolates were identified using morphological examinations and molecular diagnostics, including mitochondrial COI and 18S rDNA gene regions. Our findings revealed a diverse population of EPNs, predominantly Heterorhabditis bacteriophora with five isolates, alongside four Steinernema species (one Steinernema carpocapsae, one Steinernema affine, and two Steinernema sp.). Phylogenetic analysis, employing the mitochondrial cytochrome oxidase subunit I (COXI) and the 18S rDNA gene regions, indicated low genetic variability within H. bacteriophora and greater diversity among Steinernema species. The study contributes significant insights into the EPN biodiversity in Şırnak Province and underscores the potential of these nematodes in biological pest control, offering a sustainable alternative to chemical pesticides. The results highlight the importance of local EPN isolates in the development of effective biological control strategies and the conservation of agricultural biodiversity.

Genetic Profile of Greek Indigenous Honey Bee Populations, Local Extinctions, Geographical Distinction, and Patterns, by Using mtDNA COI and Nuclear CSD Gene Analysis Markers

Evaluation and conservation of local genetic resources of the domestic honey bee populations is important, especially in regions with high diversity levels as well as high honey bee colony density. Greece is rich in honey bee biodiversity, hosting several subspecies, with the status of them being, though, doubtful. The purpose of the present study was to investigate the genetic relationships of both stationary and movable honey bee populations, originating from many location throughout Greece. Two molecular markers were utilized, namely, the conserved mitochondrial COI gene and the highly variable complementary sex determination (CSD) gene. Samples were collected from nine distant populations: eight populations from colonies that followed the traditional stationary beekeeping model and one following the modern migratory beekeeping model type, where the hives are transferred from place to place according to the season. Regardless the beekeeping model, all populations were characterized by sufficient genetic diversity indicating no signs of inbreeding or any bottleneck effects. Nevertheless, genetic differentiation and phylogenetic analysis in comparison with haplotypes obtained from GenBank revealed a genetic admixture pattern suggesting that movement causes genetic homogeneity, occasionally in the stable reared populations as well. Interestingly, two populations, namely, Kastoria and Protokklisi, belonging to A. m. macedonica population, were significantly differentiated, supporting the maintenance of their genetic integrity. Unfortunately, on the other hand, genetic structure of the populations from Crete (Sasalos population) provided evidence that the indigenous breed from the island, A. m. adami, has probably gone extinct. Future management strategies should focus on the conservation of the local genetic resources in which distinct genetic identity has been sustained.

A new genus and one new species of the family Uristidae Hurley, 1963 (Amphipoda, Lysianassoidea) described from hydrothermal vent of the Okinawa Trough, NW pacific

A new genus of the family Uristidae Hurley, 1963 is proposed, Liuiuristis gen. nov., with new species L. thermalis sp. nov. as the type species based on specimens collected by the expedition to hydrothermal vents on the Okinawa Trough. The new genus is characterized by the shape of accessory flagellum liking cap, the outer plate of the maxilla 1 having 11 setal-teeth, the gnathopod 1 parachelate in female and subchelate in male, the rami of the uropod 3 without plumose setae and the telson not cleft. K2P divergences of the mitochondrial COI gene in taxa attributed to Liuiuristis gen. nov. is presented.

New records of Trichinella patagoniensis from Argentina

Trichinella spiralis was long considered the sole Trichinella species in Argentina. However, since 2004, various Trichinella species, including the encapsulated Trichinella patagoniensis and Trichinella britovi, as well as the unencapsulated Trichinella pseudospiralis, have been detected in the country. The present study aimed to identify Trichinella ML at the species level from cougars naturally infected from Argentina. To this end, muscle tissue samples from one cougar each from Córdoba, Neuquén, and Santa Cruz Provinces were individually analysed using the artificial digestion technique. DNA extraction and molecular identification of Trichinella species were conducted on individual muscle larvae by PCR amplification of the ESV region and subsequent PCR amplification and sequencing of the COI gene. Morphological analysis revealed muscle larvae with characteristics consistent with Trichinella genus. PCR revealed a single band of approximately 127 bp for each individual muscle larva. PCR amplification of the COI gene from each isolate generated a 309 bp band. Sequencing of the mitochondrial COI gene confirmed the identity of the parasite as T. patagoniensis. The present study documents new occurrences of T. patagoniensis in Puma concolor from Argentina, including the first detection of T. patagoniensis in Puma concolor from Córdoba and Neuquén Province. These findings expand the limited knowledge of T. patagoniensis distribution in Argentina.

Bat diversity in the Cuc Phuong National Park, Vietnam - Results from VIETBIO field training and annotated species list.

Biodiversity surveys are essential for both academic research and conservation. Integrative approaches that combine morphological, genetic and acoustic aspects for species identification can provide reliable information in taxonomy and evolution. This is especially relevant for those groups with a high degree of cryptic diversity such as bats. Here, we present the results from a field survey carried out in the Cuc Phuong National Park (CPNP) during 2019 as part of the VIETBIO project and from the examination of specimen collections preserved at the museums of CPNP and the Institute of Ecology and Biological Resources (IEBR). In addition, we include an annotated species list, based on this survey and a literature review. We here confirm that CPNP is home to at least 47 bat species belonging to 23 genera and seven families. We recorded ten of these bat species during our field survey. Obtained data in genetics (sequencing a fragment of the mitochondrial gene COI) supported the morphological identification of the recorded species for which we were able to produce these data. In addition, we include echolocation recordings obtained during our field training with the hope that they may contribute valuable insights to future work concerning the surveyed species. Results from the field survey represent a relevant contribution to biodiversity assessment efforts and, thus, support conservation and management efforts to maintain bat diversity in Vietnam.

First Report on Banana Weevil, Cosmopolites sordidus (Germar 1823) (Coleoptera: Curculionidae), an Exotic Economically Important Pest from Saudi Arabia.

We report the first record of the occurrence of the banana weevil, Cosmopolites sordidus (Germar, 1823) (Coleoptera: Curculionidae), an economically important pest of bananas (Musa spp.), from Fifa Mountains in Saudi Arabia. Moreover, we recorded the first observation of damage caused to bananas by C. sordidus in a banana farm in Jazan Province, southwestern Saudi Arabia, in March 2022. Molecular characterization using DNA sequences of the mitochondrial COI gene confirmed the morphological identification of C. sordidus. This discovery is considered a warning notice to prevent the potential establishment and spread of this dangerous pest in the banana cultivation regions in Saudi Arabia. Therefore, it is recommended that detection and monitoring of banana weevil should be undertaken in Saudi banana farms in order to restrict the dissemination of this weevil to other banana cultivation areas.

Taxonomic position of holothurian Eupentactafraudatrix (Echinodermata, Holothuroidea).

Samples of the holothurian Eupentactafraudatrix (Djakonov & Baranova in Djakonov, Baranova & Saveljeva, 1958) from the Sea of Japan were studied and the relationships of the genera Eupentacta and Sclerodactyla, as well as related taxa, were evaluated on the basis of phylogenetic analysis of the mitochondrial DNA COI and 16S rRNA genes. Using three methods, phylogenetic trees were constructed, and the degree of reliability of topological reconstructions was estimated by means of a nonparametric bootstrap test for the neighbor joining (NJ) and maximum likelihood (ML) techniques, as well as by a posteriori probability for Bayesian inference (BI) analysis. Genetic data confirm the validity of the assignment of Cucumariafraudatrix to the genus Eupentacta Deichmann, 1938. The study of sequences obtained from the holothurian specimens collected in Russian waters, near the city of Vladivostok, and determined by morphological characters clearly indicate that these specimens belong to the genus Eupentacta and are assigned as E.fraudatrix . The specimens from China in GenBank named as Sclerodactylamultipes and used in the present study, were likely misidentified, and after re-examination they may be assigned to the genus Eupentacta, either as E.fraudatrix or another taxon. Analyses of morphological characters of S.multipes unequivocally affirm that this species must be excluded from Sclerodactyla Ayres, 1851 and is provisionally assigned to the genus Sclerothyone Thandar, 1989 based on the external morphological characters and the body wall ossicles.

Description of a new species of the genus Cultellus Schumacher, 1817 (Bivalvia, Pharidae) from the South China Sea, based on integrative taxonomy

The present study describes a new species within the genus Cultellus Schumacher, 1817 collected from the South China Sea. An integrative taxonomic approach incorporating morphological comparisons, geometric morphometrics and genetic analyses was used to identify and differentiate the new species. Cultellus exilissp. nov. is distinguished from its congeners by its slender, fragile and translucent valves, curved posteroventral margins and relatively large protractor scars. The geometric morphometric analyses, based on outlines data, indicated that samples of Cultellus exilissp. nov. clustered together and were distinctly separated from other species. Multiple species delimitation results, based on the mitochondrial COI gene, support the separation of Cultellus exilissp. nov. from its related congeners. Phylogenetic analyses of a nuclear (28S rRNA) and two mitochondrial (COI, 16S rRNA) genes using Maximum Likelihood and Bayesian Inference methods revealed that the species belongs to the genus Cultellus. The superfamily Solenoidea Lamarck, 1809, which includes the families Solenidae Lamarck, 1809 and Pharidae H. Adams & A. Adams, 1856, exhibits closer affinity to the family Hiatellidae Gray, 1824 than to Solecurtidae d’Orbigny, 1846. Furthermore, we found that the genus Siliqua was clustered alongside the genera Ensiculus and Phaxas as a sister clade, which contradicts the current systematics of the subfamily within the family Pharidae. This work highlights the utility of integrative taxonomy for species identification, recognition and phylogenetic investigation.

Morphological description and DNA barcoding of Ceratophysella gracilimucronata sp. nov. (Collembola: Hypogastruridae) from China, with a key to species of the C. armata group of the Sino–Japanese Region

A new species, Ceratophysella gracilimucronata sp. nov. from Nan Ling Mountains (Guangdong Province, China), is described. It resembles C. ainu (Yosii, 1972), C. glancei Hammer, 1953 and C. falcifer Cassagnau, 1959 due to the B type chaeotataxy and short and slender mucro. Mitochondrial COI gene sequence of C. gracilimucronata sp. nov. is provided. A key to species of the C. armata group of the Sino–Japanese Region is given.

Distribution and genetic diversity of cobitid species in Iran (Teleostei: Cobitidae)

Several species of Cobitis have been reported within Iran, but only four are recognized as valid. The geographical distribution and genetic diversity of these species are not well-known. Two new populations of C. saniae and C. avicennae were reported herein based on their morphological and phylogenetic characters from the Mahabad River, a tributary of the Urmia Lake basin, and the Razavar River, a tributary of the Karkheh drainage, respectively. The genetic diversity and genetic structure of populations of C. saniae, C. avicennae, and C. faridpaki were analysed using the DNA sequences of the mitochondrial COI gene. COI sequences from various watersheds in Iran, Azerbaijan, and Georgia were used. A moderate to high level haplotype diversity and low nucleotide diversity were found in most of the populations of all three species. The AMOVA test and pairwise FST comparison revealed significant genetic structure and genetic distance between the Urmia Lake basin and other C. saniae populations. The results highlight the importance of conserving these species and their habitats, particularly in the Urmia Lake basin, where significant genetic differentiation was observed.

Molecular identification and genetic diversity of ten Pierid butterflies based on mitochondrial COI gene

The IUCN Bangladesh has documented a total of 31 species belonging to the Pieridae family in Bangladesh. There is currently limited knowledge regarding the genetic diversity and molecular relationships among these butterflies. The present investigation involved the generation of mitochondrial COI (mtCOI) gene sequences for ten species of butterflies belonging to the Pierid family. After that, BLAST analysis showed 96% to 100% similarity, and then the sequences were submitted to NCBI’s GenBank. MEGA10 and BioEdit were used to identify a 584 bp COI gene fragment with 179 variable sites and 128 parsimony-informative sites. The COI sequences' average base compositions were 38.56% T, 17.12% C, 30.18% A, and 14.12% G. While a significant AT bias (68.74%) existed among the Pierid species. The genetic distance between ten Pierid species was assessed using the Kimura 2-Parameter (K2P) algorithm, and the nucleotide differences ranged from 0.00172% to 0.24261%. Afterwards, the Maximum Likelihood (ML) method was used to construct a phylogenetic tree using ten sequences of Pierid species. These species belongs to two subfamilies, Pierinae and Coliadinae in Bangladesh. On the tree, the Pierinae subfamily of Pieridae formed a paraphyletic arrangement whereas the Coliadinae subfamily was shown to be monophyletic. The data analyses support the following relationships between the two subfamilies as follows: [(Appias + Leptosia) + (Pieris + Appias) + (Delias) + (Eurema + Catopsilia) + (Pareronia)]. This supported the theory that Pierinae and Coliadinae are sister taxa. Nonetheless, Pareronia hippia remains outside the main Pierinae group, requiring further study to resolve this issue. Finally, these studies generated ten mtCOI gene sequences that have the potential to serve as valuable references for the accurate identification of Pierid species. In addition, this result could be used in the future to reveal the subfamily relationships within the Pieridae taxonomic classification. Bangladesh J. Zool. 51(3): 289-299, 2023

Molecular Identification of the Diversity of Insects, Spiders, Lizards, Birds and Mammals of Tuensang District, Nagaland, India

ABSTRACT: DNA barcoding is a method of species identification that revolutionized the way we study and understand biodiversity. With advancements in molecular genetics and DNA sequence archives, it has become possible to use short DNA sequences to identify species, even when the specimens are difficult to distinguish by traditional morphological methods. In this article, we explore the utility of DNA barcoding in the Tuensang ecosystem of Nagaland, India and evaluate its effectiveness for species identification, informing ongoing conservation of populations and species. A total of 62 species, which included insects, spiders, lizards, birds and mammals, were collected from Tuensang areas of northeast India and identified using DNA barcodes. DNA was extracted from muscle tissue and PCR was done with two pairs of primers targeting the mitochondrial COI gene. Sanger sequencing was employed and the obtained sequences were analysed to identify the species and reconstruct the evolutionary relationships amongst them. Our results provided molecular characterization of species from Tuensang areas of Nagaland for the first time.

The arboreal snail genus Amphidromus Albers, 1850 (Eupulmonata, Camaenidae) of Southeast Asia: 1. Molecular systematics of some Vietnamese species and related species from Cambodia, Indonesia, and Laos.

This paper reassesses the taxonomy and systematics of 11 arboreal snail species in the genus Amphidromus from Vietnam, Cambodia, Indonesia and Laos (A.bozhii Wang, 2019, A.buelowi Fruhstorfer, 1905, A.costifer Smith, 1893, A.haematostoma Möllendorff, 1898, A.ingens Möllendorff, 1900, A.madelineae Thach, 2020, A.metabletus Möllendorff, 1900, A.pankowskianus Thach, 2020, A.placostylus Möllendorff, 1900, A.roseolabiatus Fulton, 1896, and A.thachi Huber, 2015). The taxonomic validity of each species is supported by a phylogenetic analysis of mitochondrial COI and 16S rRNA gene fragments from 17 ingroup taxa. Amphidromusbuelowi was found to comprise two populations from two distant localities, one from Mount Singgalang, West Sumatra, Indonesia and the other from southern Vietnam. The samples from southern Vietnam were previously described as A.asper Haas, 1934 and A.franzhuberi Thach, 2016, but they are now treated as junior synonyms of A.buelowi in this study. In addition, two species from Vietnam are described as new to science, viz. A.asperoides Jirapatrasilp & Lee, sp. nov. and A.ingensoides Jirapatrasilp & Lee, sp. nov., each of which is conchologically comparable to A.buelowi and A.ingens, respectively.

Enigmatic and extravagant genitalia in the spider genus Mastigusa (Araneae, Cybaeidae) - a taxonomic revision.

Mastigusa is a genus of small palearctic spiders that has recently been moved to the family Cybaeidae after the first inclusion of the genus in a phylogenetic matrix. Three species are currently recognised: M. arietina , M. lucifuga and M. macrophthalma . The status and delimitation, though, has always been problematic due to inconsistency in the characters used to discriminate between these, leading to great confusion in identity and distribution. We present a detailed morphological redescription of the genus and a taxonomic revision of the included species by the combined use of morphological data and molecular species-delimitation techniques based on the mitochondrial COI gene. The status of the three currently described species has been reevaluated and Mastigusa diversa was revalidated based on material from the Iberian Peninsula, North Africa and the United Kingdom. The distribution of Mastigusa species is updated based on novel taxonomic considerations, and comments on the natural history and ecological differences observed in the species are provided. ZooBank: urn:lsid:zoobank.org:pub:AAD3FAED-440F-4295-B458-455B1D913F81.

Aedes unalom sp. nov. in Cambodia, a new Stegomyia species close to Aedes albopictus (Diptera, Culicidae)

Preliminary genetic analysis of cytochrome c oxidase subunit 1 (COI) gene of specimens initially assigned to the mosquito Aedes albopictus based on morphology revealed two clusters. This observation led to further genetic and morphological analysis: a total of 86 Stegomyia specimens identified morphologically as Ae. (Stegomyia) albopictus, were collected between 2017 and 2019 in Cambodia. Their mitochondrial DNA COI gene and 5.8S-ITS2 rDNA were sequenced for molecular characterization and genetic analysis as well as Wolbachia presence/type. In 2022, additional Stegomyia specimens were collected for COI sequencing and morphological characterization. Of the 86 Stegomyia specimens, 14 specimens had divergent COI and 5.8S-ITS2 sequences compared to other Stegomyia species, and were negative for the presence of Wolbachia, unlike Ae. albopictus specimens which carried wAlbA and/or wAlbA B types. Additional trapping in 2022 resulted in the colletion of 11 specimens with similar divergent COI and 5.8S-ITS2 sequences. Sequence blast results did not match these COI and 5.8S-ITS2 sequences, neither within Stegomyia taxa nor other organisms. Lastly, after morphological examinations, specific characters were observed in adult mosquitoes and male genitalia, allowing the specimens to be described as a new Stegomyia species named Aedes unalom Maquart & Hide, sp. nov. This species lives in sympatry with other Stegomyia species such as Ae. albopictus or Ae. aegypti and does not carry Wolbachia. This new species should be considered as a potential arbovirus vector.

A filarial parasite potentially associated with the health burden on domestic chickens in Japan

Chickens in free-range environments are at risk of exposure to various pathogens, such as filarioids transmitted via hematophagous vectors. However, the study of filarioids in poultry has been largely neglected compared to the extensive studies focused on viruses, bacteria, and protozoa. Here, we performed histological and molecular investigations of the filarioids detected in domestic chickens from two different flocks in Hiroshima Prefecture, Japan. In the first case, adult worms were present in the pulmonary artery and right ventricle, and microfilariae were present in multiple organs of deceased chickens. In the second case, similar filarioids were detected in the organs and blood of one necropsied layer. Phylogenetic analysis using 18S rRNA gene fragments positioned the filarioid in the same clade as that of Onchocercidae sp., previously identified in a deceased chicken from Chiba Prefecture, Japan, that is located 500 km away from Hiroshima Prefecture. Based on 28S rRNA and mitochondrial COI gene fragments, the filarioid was positioned distinctly from previously reported genera of avian filarioids. These results suggest that the filarioids are potentially associated with the health burden on domestic chickens and belong to the genus Paronchocerca. Furthermore, we developed a nested PCR assay targeting mitochondrial COI and detected the parasite DNA from the biting midge Culicoides arakawae captured near the flock, suggesting that it serves as a vector. Our findings fill the knowledge gap regarding avian filarioids, laying the groundwork for future studies examining the epidemiology, life cycle, and species diversity of this neglected parasite group.

Reappraisal of Eiconaxius farreae Ortmann, 1891 and Eiconaxius mortenseni Sakai, 1992 (Decapoda: Axiidea: Axiidae), with description of a new species from Japan.

The sponge associated axiid shrimp Eiconaxius farreae Ortmann, 1891 was originally described based on specimens from Sagami Bay, central Japan. Morphological examination of many specimens of Eiconaxius collected from Sagami Bay and nearby areas, and genetic data from the mitochondrial COI and 16S rRNA genes have revealed that three species are represented. This finding led to a reappraisal of the identity of E. farreae and E. mortenseni Sakai, 1992, also originally described from Sagami Bay. It has been clarified that two species (E. farreae and an undescribed species) were mixed in the syntype material of E. farreae, and consequently, a lectotype of E. farreae is designated in the interest of nomenclatural stability. Here, E. farreae and E. mortenseni are redescribed, and the third species is described as new, E. reconditus. The new species is morphologically very similar to E. mortenseni. Differentiating characters among closely allied species are reassessed. Previous records of E. farreae are reviewed in light of the present findings.

Molecular Evidence Reveals Taxonomic Uncertainties and Cryptic Diversity in the Neotropical Catfish of the Genus Pimelodus (Siluriformes: Pimelodidae).

Pimelodus is the most speciose genus of the family Pimelodidae, and is amply distributed in the Neotropical region. The species-level taxonomy and phylogenetic relationships within this genus are still poorly resolved, however. These taxonomic problems and the general lack of data have generated major uncertainties with regard to the identification of specimens from different localities. In the present study, we applied a single-locus species delimitation approach to identify the MOTUs found within the genus Pimelodus and provide sound evidence for the evaluation of the species richness of this genus in the different river basins of the Neotropical region. The study was based on the analysis of sequences of the mitochondrial COI gene of 13 nominal species, which resulted in the identification of 24 consensus MOTUs. Only six nominal species were recovered as well-defined molecular entities by both the traditional barcoding analysis and the molecular delimitation methods, while the other seven presented cryptic diversity or persistent taxonomic uncertainties. The lineages identified from the Parnaíba ecoregions, Amazonas Estuary and Coastal Drainages may represent a much greater diversity of Pimelodus species than that recognized currently, although a more detailed study of this diversity will be necessary to provide a more definitive classification of the genus.

Recent molecular techniques to strengthen ecological studies in echinoderms

Introduction: Echinoderms, an integral component of marine ecosystems worldwide, have captivated scientific interest for centuries. Despite this longstanding attention, comprehending key facets such as trophic relationships, diet composition, and host-microbiota relationships still represents a challenge using traditional techniques. Recent years, however, have witnessed a transformative shift, thanks to the emergence of advanced molecular techniques, offering new approaches to strengthen ecological studies in echinoderms.
 Objective: Explore how recent advancements in molecular tools have impacted ecological research on echinoderms. Specifically, we aim to investigate the potential of these tools to shed light on trophic interactions, diet composition, and the characterization of gut microbial communities in these organisms.
 Methods: Available literature was used to clarify how novel molecular techniques can improve ecological studies. The focus is diet, trophic relationships, and gut microbiota.
 Results: Traditionally, studies of stomach contents using compound microscopy have provided an idea of ingested material; nevertheless, sometimes a simple magnified visualization of dietary content does not allow exhaustive identification of the entire food spectrum, as it is limited due to the rapid digestion and maceration of food items within the echinoderm’s digestive tract. The use of DNA-metabarcoding, targeting specific DNA regions, such as the mitochondrial COI gene, has allowed us to enhance the accuracy and precision of diet characterization by enabling the identification of prey items down to the species or even genetic variant level, providing valuable insights into specific dietary preferences. Another approach is the use of stable isotopes, particularly carbon and nitrogen, which provide a powerful tool to trace the origin and flow of nutrients through food webs. By analyzing the isotopic signatures in muscular tissues and food items, we can discern the sources of their primary food items and gain insights into their trophic position within the ecosystem. Lastly, a third new technique used to elucidate the characterization of the prokaryotic community is 16S rRNA sequencing. This method allows us to explore the composition and dynamics of the digestive tract microbial communities.
 Conclusions: This is a promising era for ecological research on echinoderms, where advances of molecular tools have enabled an unprecedented level of detail, resolving longstanding challenges in comprehending their trophic interactions, diet composition, and host-microbiota relationships, and opening new avenues of investigation in ecological studies.