Cytochrome Oxidase Subunit I Sequences Research Articles

Range extension of Blackstripe Lizardfish, Synodus nigrotaeniatus Allen, Erdmann & Peristiwady, 2017 (Actinopterygii, Aulopiformes, Synodontidae), from Jakarta Bay, Indonesia

Three specimens (194.4–203.8 mm standard lengths) of the lizardfish Synodus nigrotaeniatus Allen, Erdmann & Peristiwady, 2017, collected from Jakarta Bay, western Indonesia, represent a significant range extension for the species, which was previously known from only six specimens collected in Lembeh Strait, North Sulawesi, eastern Indonesia. Morphological comparisons with available data from the type specimens and molecular data from the mitochondrial cytochrome oxidase subunit I (COI) gene are presented. The COI sequence data show a 4% genetic difference from the related Synodus sageneus Waite, 1905.

Identification and Genetic Diversity of Spodoptera frugiperda J. E. Smith (Lepidoptera: Noctuidae) in Egypt

Fall armyworm, Spodoptera frugiperda, is a serious agricultural pest native to tropical and subtropical regions of the Western Hemisphere and has invaded Africa and further spread into most countries of Asia within two years. In Egypt, researchers have conducted thorough investigations into the behavior of the fall armyworm and various methods to manage its impact. This study aims to further our understanding of the genetic diversity of fall armyworm populations in Egypt. By collecting specimens from five provinces across the country, we sought to analyze their genetic makeup. Through examination of partial sequences of the mitochondrial cytochrome oxidase subunit I (COI), we identified three distinct haplotypes. Phylogenetic analysis suggests that the primary sources of Spodoptera frugiperda in Egypt likely stem from both Asian and African origins. Employing the PCR-RFLP technique on the complete COI sequence, we were able to discern genotype patterns within the fall armyworm population. Our findings indicate the presence of two distinct strains—the Corn and Rice strains—within Egypt. This research contributes essential insights into the genetic diversity of insects in Egypt, providing valuable knowledge that can inform more effective strategies for managing this agricultural pest.

Four new species of Triraphis Ruthe, 1855 (Braconidae, Rogadinae) from a Mexican tropical dry forest and morphological descriptions of T. bradzlotnicki Sharkey, 2021 and T. davidwahli Sharkey, 2021

The koinobiont endoparasitoid genus Triraphis Ruthe, 1855 (Rogadinae Foerster, 1863) is a group of braconid wasps that contains 74 species distributed along the Nearctic, Neotropical, Oriental and Palearctic regions. We amplified a fragment of the cytochrome oxidase subunit I (COI) for 19 specimens of Triraphis from the Chamela Biological Station (CBS), a region mainly composed of tropical dry forest near the Pacific coast of Jalisco, Mexico. Based on genetic distances among specimens of Triraphis from the CBS and all COI sequences of BINs assigned to Triraphis and Rogas Nees, 1819 available in the BOLDSYSTEMS database, we identified three clusters in the CBS that correspond with T. bradzlotnicki Sharkey, 2021, T. davidwahli Sharkey, 2021 and T. defectus Valerio, 2015, which were previously described from Costa Rica. Based on morphology, we identified individuals of T. fusciceps Cresson, 1869 and provided COI sequences of this species for the first time. Four genetic clusters of Triraphis correspond to four new species that are described here: T. kardia sp. nov., T. ocellatus sp. nov., T. divergens sp. nov. and T. luzabrilae sp. nov. Since T. bradzlotnicki and T. davidwahli were exclusively described with molecular data (COI), we morphologically described them based on Mexican specimens.

Molecular identification of sharks from the genus Sphyrna (Elasmobranchii: Chondrichthyes) in Maranhão Coast (Brazil).

Sharks of the genus Sphyrna are under intense exploitation globally. In Brazil's northern coast, this genus represents a high proportion of fisheries landings and comprises four species. However, due to difficulty of specific identification when specimens are landed, most of the records are limited to the genus level. Here we analyzed the effectiveness of ITS2 (Internal Transcribed Spacer 2 of rDNA) fragment length protocol (Abercrombie et al., 2005) for identifying hammerhead shark species, comparing with the analysis of COI (Cytochrome oxidase subunit I) and ITS2 sequences. We evaluated samples of muscle tissue acquired in the main fishing ports of Maranhão: Carutapera, Raposa e Tutóia. Sampling was conducted between March 2017 to March 2018 and complemented with material deposited in collection (2015). COI results indicated the occurrence of endangered species which are prohibited to be landed. These include Sphyrna mokarran (67%), S. lewini (15%), S. tudes (3%), and S. tiburo (15%). For the ITS2 marker, we investigated the optimization of the protocol developed by Abercrombie (2005) for to improve the use in this geographical area througout design of a new primers.

Confirmation of hilsa shad (Tenualosa ilisha) in Vietnamese waters: a morphological and genetic analysis

Abstract One specimen of tropical shad was caught from the Giang Thanh River, Kien Giang province, Vietnam in a survey on 16 October 2022. We identified the specimen as the hilsa shad, Tenualosa ilisha Hamilton, 1822 using morphological analysis, and further validated by its cytochrome oxidase subunit I (COI) sequence. The specimen was 418 mm long, 1428 g in weight, with a head length of 29.0% and pectoral fin length of 31.1% of its standard length. Notably, the presence of 34 scutes, a higher gill raker count and a caudal fin length within the moderate range for Tenualosa species distinguished it from T. macrura, T. toli and T. reevesii. The COI sequence of the sample matched closely to the T. ilisha. The results confirm that T. ilisha still endures Vietnamese water, where it was thought to be extinct. Climate change and Indo-Pacific Ocean currents may introduce expansion of distribution area of the T. ilisha. Further studies on distribution of the T. ilisha and other Tenualosa species and their dynamics are needed.

Evergreen forests on the Korean Peninsula faced a new threat: Schizomyia castanopsisae (Jat-bam-na-mu-hok-pa-ri) inducing galls on reproductive organs of Castanopsis sieboldii in the Yokjido Island Natural Monument Forest

Unnoticed and silently, a certain midge has emerged that could pose a threat to the evergreen forests on the Korean Peninsula and the associated island ecosystems. We report the discovery of an unrecorded species on the Korean Peninsula, identified as Schizomyia castanopsisae Elsayed & Tokuda, 2018 (Diptera: Cecidomyiidae). This previously unrecorded gall midge species induces galls on a reproductive organ of Castanopsis sieboldii, specifically the inflorescences, and was found in the natural monument forest on Yokjido Island. A total of 40 larvae were collected from 8 inflorescence galls, each obtained from individual hosts within the forest. Morphological examinations and mitochondrial DNA cytochrome oxidase subunit I (COI) region sequencing were conducted for each specimen, confirming the identification of the gall inducer as S. castanopsisae. The COI sequences from the 40 specimens collected on Yokjido Island were identical, showing a 99.8% match with individuals from Kyushu, Japan. Additionally, a maximum likelihood tree analysis revealed a sister relationship between Yokjido Island and Kyushu individuals. Considering the tropical nature of gall midge species, it suggests recent northward migration from Kyushu to Yokjido Island. This species not only significantly reduces acorn production but also has the potential to negatively impact organisms associated with acorns. Drawing from cases in Japan, this species has the potential to rapidly dominate evergreen broad-leaved forests on numerous islands in the Korean Peninsula. Therefore, urgent additional research on aspects such as natural enemies of this species, its dispersal mechanisms, and other relevant factors is necessary. We also investigated the distribution of trees with inflorescences gall-induced by S. castanopsisae in the Yokjido Island Natural Monument Forest. The occurrence frequency of these galls is estimated to be approximately 10 percent.

Genetic Variability and Connectivity in the Western Mediterranean Populations of the Bathyal Crab Geryon longipes

Geryon longipes is a crab species that inhabits the muddy bottoms of the middle and lower slopes, as well as bathyal bottoms ranging from 400 to 2000 m in depth. To assess its molecular diversity, a fragment of 572 bp of the COI (Cytochrome Oxidase subunit I) mitochondrial gene was sequenced in eight Western Mediterranean locations. Within the studied area, two oceanographic fronts are present (Almeria-Oran Front and Ibiza Channel). From the 124 sequences obtained, only 7 distinct haplotypes were identified. The population distribution indicated three well-differentiated regions: the Alboran Sea, the Gulf of Vera and the Levantine/Catalan coasts. The molecular diversity was compared with that obtained in the same year for the same gene in Liocarcinus depurator, a crab species that is captured on the continental shelf and upper slope (40 to 500 m). The estimates of molecular diversity parameters for the COI gene fragment were rather similar between both species, but the number of haplotypes was higher for L. depurator. Finally, the obtained COI sequences of G. longipes were compared to those from other populations of the species distribution range, recovered from the DNA repository. Only one additional, different haplotype was reported (Sicily), whereas all the rest were common with those described in our study. Therefore, the COI gene fragment would indicate that all the sequences analysed in the Mediterranean and NE Atlantic belong to the same species, G. longipes.

Identification and reproductive isolation of Euborellia species (Insecta, Dermaptera, Anisolabididae) from East and Southeast Asia.

Euborellia (Anisolabididae: Anisolabidinae) is one of the most speciose genera of earwigs (Dermaptera), and its species-level classification is difficult. To settle the classification of brachypterous species with abbreviated tegmina recorded from East and Southeast Asia, we examined the morphology and reproductive isolation of three tentative Euborellia species, and analyzed the DNA barcoding region of the mitochondrial cytochrome oxidase subunit I (COI) gene. The observed complete reproductive isolation among the three Euborellia taxa and considerable differentiation in the COI sequences clearly show that each should be treated as a separate species. Based on morphology, distribution and the DNA sequence, we identify Euborellia sp. 1 of Malaysia as E.annulata (Fabricius), a circumtropical cosmopolitan with no records of a fully winged form. Samples from Ioto Island (= Iwo-jima Island: Ogasawara Islands, southern Japan) were also identified as this species. Euborellia sp. 3, from the main islands of Japan, was generally larger and lacked a Y-shaped pigmented area on the penis lobe, which is characteristic of Euborellia sp. 1. We propose reinstating E.pallipes (Shiraki) as the oldest name for this taxon. Euborellia sp. 2, even the brachypterous form, can be distinguished from these two species by its paler coloration (particularly the femora), ecarinate post-abdomen, and the shape of the male genitalia (parameres). We tentatively identify this species as E.philippinensis Srivastava based on the morphology of the brachypterous form, although the macropterous form cannot be distinguished from E.femoralis (Dohrn).

South(East) by Southwest: Identification of a New Halocaridina rubra Holthuis, 1963 (Decapoda: Atyidae) Genetic Group From O‘ahu, Hawai‘i

The anchialine ecosystem, comprised of coastal landlocked habitats containing brackish water, experiences tidal fluctuations due to simultaneous underground connections with the sea and terrestrial aquifer system. Anthropogenic impacts have led to substantial habitat degradation and loss, potentially making the anchialine ecosystem and its biota one of Hawai‘i’s most threatened. Prior analyses of mitochondrial (mtDNA) cytochrome oxidase subunit I (COI) sequences from the Hawaiian anchialine atyid shrimp Halocaridina rubra revealed a potential cryptic species complex with strong regional endemism. This study hypothesized that a Halocaridina population discovered in 2018 in southeast O‘ahu, an area with no historically documented anchialine habitats but where a specimen was collected in 1998, represents a unique lineage or genetic group endemic to the region. Comparison of newly generated mtDNA COI sequences to previous ones identified the population as belonging to the South O‘ahu lineage of Halocaridina. However, fixed mutations and significant genetic differentiation distinguish it from the closely related ‘Ewa genetic group of southwest O‘ahu. Given this, we propose the new Maunalua genetic group for Halocaridina from southeast O‘ahu, with an apparent split between groups occurring at approximately the Holocene-Pleistocene Epoch boundary, corresponding well to the geological age of where the new population was discovered. Notably, the 1998 specimen shared the same distinctive coloration as the Maunalua and ‘Ewa genetic groups, implying inclusion within the South O‘ahu lineage. Conservation efforts should consider the currently recognized 15 Halocaridina genetic groups since they represent unique units from all others in both their genetics and geographic distribution.

Genetic diversity of cryptic species of Bemisia tabaci in Asia.

Bemisia tabaci is a species complex consisting of various genetically different cryptic species worldwide. To understand the genetic characteristics and geographic distribution of cryptic species of B. tabaci in Asia, we conducted an extensive collection of B. tabaci samples in ten Asian countries (Bangladesh, Indonesia, Japan, Korea, Myanmar, Nepal, Philippines, Singapore, Taiwan, and Vietnam) from 2013 to 2020 and determined 56 different partial sequences of mitochondrial cytochrome oxidase subunit I (COI) DNA. In addition, information on 129 COI sequences of B. tabaci identified from 16 Asian countries was downloaded from the GenBank database. Among the total 185 COI sequences of B. tabaci, the sequence variation reached to 19.68%. In addition, there were 31 cryptic species updated from 16 countries in Asia, that is, Asia I, Asia I India, Asia II (1-13), Asia III, Asia IV, Asia V, China 1-6, MEAM (1, 2, K), MED, Australia/Indonesia, Japan (1 and 2). Further, MED cryptic species consisted of 2 clades, Q1 and Q2. This study provides updated information to understand the genetic variation and geographic diversity of B. tabaci in Asia.

DNA Barcoding of Chironomid Larvae (Diptera: Chironomidae) from Large Rivers in South Korea to Facilitate Freshwater Biomonitoring and Public Health Surveillance.

Chironomid larvae are among the dominant benthic macroinvertebrates in all types of water systems in South Korea. They may pass through pipes in rivers (raw water) and occur in drinking water, thus creating public health issues. However, little is known about the larval stages of chironomids in large South Korean rivers. Therefore, we examined larval–adult associations in chironomids inhabiting major rivers used as water sources. The larvae were collected in 2015 and 2016 from nine locations along the four largest rivers in South Korea using a Ponar grab. Cytochrome oxidase subunit I (COI) sequences were generated from the larval specimens, and the species were identified by comparing these sequences to those in a newly constructed DNA barcode library of Chironomidae in South Korea. The samples from the four rivers yielded 61 mitochondrial COI sequences belonging to 18 species, including Hydrobaenus kondoi Saether, 1989, which was reported for the first time in the Korean Peninsula. Further, morphological identification of the larvae was conducted, and a pictorial taxonomic key to Chironomidae species in large rivers in South Korea was developed to facilitate freshwater biomonitoring research. Finally, an action flow chart was created for the rapid identification of chironomid larvae in infested drinking water or water purification facilities.

A genetic approach for authentication on morphological differences of cultivated pompano species in Indonesia

Abstract. Hakim AA, Dikrurahman, Muhlis S, Astuti RP, Sari DW, Kamal MM. 2022. A genetic approach for authentication on morphological differences of cultivated pompano species in Indonesia. Biodiversitas 23: 4561-4569. Due to the increasing demand for animal protein, the Batam Marine Cultivation Fisheries Center (BPBL Batam) developed pompano (Trachinotus spp.) for aquaculture. Because of the different external characteristics, local communities recognized three types of pompano, i.e., bintang, emas, andhibridpompano. The study aimed to prove the authenticity of cultivated pompano (Trachinotus spp.) with morphological differences based on a DNA barcoding approach with 16S ribosomal RNA and cytochrome oxidase subunit I (COI) partial genesequences. A total of 30 barcode sequences from COI and 16S rRNA genes were obtained from three types of pompano, and all samples were validated as Trachinotus blochii with percent identity of 99.85-100% by COI and 100% by 16S rRNA. Emas, bintang, and hibrid pompano also have the same or very similar GC content both based on COI and 16S rRNA sequences. The average genetic distances calculated between species in the genusTrachinotus were 0.09 and 0.02 among COI and 16S rRNA sequences, respectively. Phylogenetic analysis constructed from COI and 16S rRNA gene sequences of all types of pompano and related species segregated genus into one clade (T. blochii) and the outgroup (other species) as another clade. This study contributed essential genetic data to the NCBI database both COI and 16S rRNA gene sequences. Despite having morphological differences, all types of pompano were successfully authenticated into the same species because they have identical nucleotide base arrangements and can be presumed from the same ancestor.

Identification of Phalacronotus bleekeri (Günther, 1864) (Siluridae) From the Mekong Delta, Vietnam and Use of Morphological Analysis to Separate Populations

This study identified Phalacronotus to species level and examined its morphometric variation among three collection localities, and between sexes, in the Mekong Delta, Vietnam. Specimens were collected from local markets and fishers, including An Giang (n = 36) and Can Tho (n = 36) in the Hau River and Tien Giang (n = 30) in the Tien River for morphological measurements and DNA barcoding analysis. Eight mitochondrial cytochrome oxidase subunit I (COI) sequences of Phalacronotus sp. shared 99.6 ± 0.23 % similarity with five GenBank (GB) P. bleekeri sequences and differed by 7.6 % to 13.3 % from seven GB P. apogon sequences. The Vietnamese specimens of Phalacronotus were similar to P. bleekeri in number of anal fin rays (75–80) and the shape of the upper jaw teeth. Thus, the COI sequences and these morphological characteristics indicate that Phalacronotus sp. samples collected in the Mekong Delta are Phalacronotus bleekeri (Günther, 1864). Morphometric characteristics differed between populations in 15 of 19 indices (P < 0.05) and between females and males in three characteristics relating to the belly. Head characteristics, body depth, and caudal peduncle depth were the main parameters contributing to the inter-population variation. Based on size-adjusted data, 96.7 % of specimens were correctly classified from the Tien Giang population, while 27.8 % and 33.3 % were misclassified between the Can Tho and An Giang populations, respectively. These results indicate that morphometric parameters of P. bleekeri varied mainly between populations in the two Mekong River tributaries.

Phylogeography of the veined squid, Loligo forbesii, in European waters

The veined squid, Loligo forbesii Steenstrup, 1856, occurs at the European Shelf areas including the Azores and represents a valuable resource for the European commercial fishery in the North East Atlantic. However, very little is known about its population structure and phylogeography. This lack of knowledge also impedes the development of sustainable fishery management for this species. The present study combined the use of two types of markers that retrieve patterns of gene flow in different time spans; the analysis of 16 nuclear microsatellites and sequencing of the mitochondrial cytochrome oxidase subunit I (COI). Whereas the high mutation rate of microsatellites allows the description of recent patterns of connectivity in species, the lower mutation rate of COI provides phylogeographic patterns on a longer timescale. A total of 347 individuals of L. forbesii were investigated from nearly the entire distribution range of the species, including the North East Atlantic Shelf, the Azores and the Mediterranean. Individuals from the Western and Eastern Mediterranean Sea have never been included in a genetic study before. We were able to analyse COI sequences from all 12 sampling areas and define three clades of L. forbesii. Due to our large sampling area, we are presenting 13 COI-haplotypes that were previously unknown. The microsatellite analysis does not include the Azores but three main clades could be identified at the remaining 11 sampling sites. Low FST values indicate gene flow over large geographical distances. However, the genetically significant differences and an additional slight grouping in the microsatellite structure reveal that geographical barriers seem to influence the population structure and reduce gene flow. Furthermore, both markers provide strong evidence that the observed phylogeographic pattern reflects the geographical history of the Azores and the Mediterranean Sea.

Phylogenetic Analysis of the Dominant Non-biting Midge Forcipomyia bikanni (Diptera: Ceratopogonidae) around West Lake, Hangzhou, China

Abstract The nonbiting midges are tiny insects with a wide distribution around West Lake, China. In this study, the seasonal dynamics of the local dominant midge species was investigated. Phylogenetic trees of this species also were analyzed to discover its evolutionary history. Ultraviolet (UV) light traps were used for surveillance around West Lake in the period from April 2017 to November 2018. External morphological identification was performed using a stereomicroscope. Two genes of adult female midges that encoded the cytochrome oxidase subunit I (COI) and internal transcribed spacer 1 (ITS-1) were sequenced and aligned online using GenBank nucleotide database and the Molecular Evolutionary Genetics Analysis (MEGA) software 10.1.7. According to the field surveillance in 2017–2018, Forcipomyia bikanni Chan and LeRoux (Diptera: Ceratopogonidae) is the representative dominant species of West Lake, with its activity peaking in August and October. The COI and ITS-1 gene sequences of F. bikanni (XH01-5) were 523 bp and 315 bp, respectively. The final phylogenetic tree of the COI implied that F. bikanni (XH01-5) has 97.9% significant similarity with conspecific F. bikanni (LC015045) from the adjacent Fujian Province, China (E-value ≤ 0.1%). Furthermore, the ITS-1 sequences with 98% likelihood showed the highest linkage between F. bikanni (XH01-5) and F. townsvillensis (Taylor) (HM775502-HM775504) with different branches. Thus, the final unrooted phylogenetic trees of COI and ITS-1 are essential tools for reconstructing the evolutionary histories of nonbiting midges.

Two new pseudocryptic species in the medium-sized common European land snails, Fruticicola Held, 1838; as a result of phylogeographic analysis of Fruticicola fruticum (O. F. Müller, 1774) (Gastropoda: Helicoidea: Camaenidae)

Fruticicola fruticum (O. F. Müller, 1774), a medium-sized helicoid snail in the Camaenidae, has a wide range in Europe, reaching from the Urals and the Caucasus to the Balkans, and from the southern part of Scandinavia, through Central Europe to eastern and central France and northern Italy. There are numerous studies on its distribution, biology, life cycle, etc., but little is known about the genetic diversity of this taxon. Here, we studied the phylogeny and phylogeography of F. fruticum using two mitochondrial markers: cytochrome oxidase subunit I (COI) and 16S ribosomal RNA (16S); and four nuclear markers: 18S ribosomal RNA (18S), 28S ribosomal RNA (28S), internal transcribed spacer (ITS-2), and histone 3 (H3). The study was based on 59 populations sampled across the range. Whereas nuclear markers showed little differentiation, phylogenetic analysis of COI sequences clearly confirmed the distinctness of the European Fruticicola and Asian Bradybaena (p-distance 0.229). Within Fruticicola 54 haplotypes were detected, haplotype diversity (Hd) = 0.973 ± 0.006, nucleotide diversity (π) = 0.137 ± 0.005. ABGD and PTP delimitation analyzes distinguished eight mOTUs. Two sequences (our mOTU C) from Russia were published in the GenBank as two distinct species: F. schrenckii and F. transbaicalia. Seven further mOTUs identified in our study formed three distinct lineages, regarded as species. The first (mOTU A and mOTU B), represented by 40 populations, occupies a wide range across northern and central Europe, extending east to Ukraine and south to northern Croatia (mOTU B). It encompasses the type locality of F. fruticum, and can be recognized as F. fruticum sensu stricto. Another lineage (mOTU D and mOTU E), represented by six populations in central Romania, appears to form another species. Both mOTUs were found together in one population. A third lineage, containing mOTUs F, G and H, represented by 14 populations, was distributed across the Balkans from N.E. Croatia to Bulgaria. p-distances between the three species ranged from 0.172 to 0.219, and between all the mOTUs, pooled together, from 0.172 to 0.258. The highest genetic diversity was found in species 3 (0.112) and the lowest in species 1 (0.025), despite its largest geographic distribution. Pairwise p-distances, Tamura 3-parameter distances, composite likelihood distances, as well as the coancestry coefficient FST, calculated for all populations pooled together were significantly associated with geographic distance, but this was not the case within each of these three species. The significant association for all populations reflected high diversity between the species coupled with high geographic distances between their populations, not the character of intraspecies diversity. With a few exceptions, there hold a rather infinite island model with low migration. AMOVA detected 78% of the variance between the three species, 18% among populations within the species, and only 3.6% within the populations. The low genetic diversity of widespread F. fruticum s. stricto, compared with much higher diversity of two narrowly distributed newly found species of Fruticicola, may reflect the rapid spread of the former into previously uninhabitable regions, while the latter were able to maintain populations in glacial refugia. The estimated time of divergence between the three species, 1.7–2.19 mya, suggests their ancestors’ isolation in southern European refugia during the lower Pleistocene, the Gelasian/Calabrian. There was no clear association of variation in shell morphology and lineage or mOTU identity; on external characters, these species are semicryptic, subtle differences in reproductive anatomy among them were found.

New records of the occurrence of Megaleporinus macrocephalus () (Characiformes, Anostomidae) from the basins of the Itapecuru and Mearim rivers in Maranhão, Northeastern Brazil.

The "piaussu", Megaleporinus macrocephalus is an anostomatid fish species native to the basin of the Paraguay River, in the Pantanal biome of western Brazil. However, this species has now been recorded in a number of other drainages, including those of the upper Paraná, Uruguay, Jacuí, Doce, Mucuri, and Paraíba do Sulrivers. This study presents two new records of the occurrence of M. macrocephalus, in the basins of the Itapecuru and Mearim rivers in the state of Maranhão, in the Brazilian Northeast. The piaussu is a large-bodied fish of commercial interest that is widely raised on fish farms, and its occurrence in the Itapecuru and Mearim rivers is likely the result of individuals escaping from fish tanks when they overflow during the rainy season. Morphological analyses and sequences of the Cytochrome Oxidase Subunit I (COI) gene confirmed the taxonomic identification of the specimens as M. macrocephalus. The COI sequences were 99.66% similar to those of M. macrocephalus deposited in the BOLDSystems database. These records extend the known distribution of M. macrocephalus to the basins of the Itapecuru and Mearim rivers in the Brazilian Northeast, highlighting a new case of introduction of exotic fish species into Brazilian river basins.

The first genetic characterization of Setaria marshalli (Nematoda, Spirurida) with reliable DNA barcoding based on a mitochondrial genetic marker.

Setaria marshalli is a mosquito-borne filarial nematode that causes infection in calves younger than two years old. In the present study, nematodes were obtained from a calf in Japan and morphologically identified as S. marshalli. Additionally, the partial cytochrome oxidase subunit I (COI) region (596 bp) was analyzed for the first time to establish a reliable DNA barcode. Nucleotide sequences of COI were identical among the seven worms obtained. The COI region can be a useful marker for species discrimination in the case of S. marshalli since nucleotide variations observed between the closest congener, Setaria cervi (51/596 bp), were sufficient to allow species discrimination. However, the phylogenetic relationship of S. marshalli with its congeners was unclear in a maximum likelihood tree. We found that the partial COI sequence of S. marshalli analyzed in the present study matched a relevant section of the complete mitochondrial genome of S. labiatopapillosa that was deposited in the International Nucleotide Sequence Database. This finding suggests that S. marshalli was misdiagnosed as S. labiatopapillosa in a previous study. It is crucial to conduct accurate morphological analyses to obtain reliable molecular information regarding Setaria nematodes.

Morphological and Molecular Evidence Reveals the Longnose Skate Zearaja brevicaudata (Marini, 1933) to be a Senior Synonym of Dipturus lamillai Concha, Caira, Ebert & Pompert 2019.

Longnose skates have great economic importance in South American fisheries, and in order to preserve them, it is important to have a well-defined taxonomic status of their species. Dipturus lamillai was recently described for Malvinas Islands waters based on morphological and molecular comparisons with Zearaja chilensis. Although D. lamillai has been compared with several congeneric species, it was not properly compared with the morphologically similar Zearaja brevicaudata, the most abundant longnose skate in the Southwest Atlantic. Here, these species were compared by morphological and molecular analyses in order to evaluate their conspecificity. Linear morphometric variables of holotype and paratypes of D. lamillai and 69 specimens of Z. brevicaudata were compared and investigated using Principal Component Analysis. In addition, thorn patterns, denticle distributions, color, and clasper morphology were compared. No body proportions or other single character that could differentiate D. lamillai from Z. brevicaudata were found. Molecular analyses comprised of the comparison of the Cytochrome oxidase subunit I (COI) and the NADH dehydrogenase subunit 2. The results of the Maximum Likelihood (ML) carried out for each molecular marker showed that sequences from D. lamillai clustered together with those of Z. brevicaudata, and the molecular distance determined by Kimura two-parameter were lower than the expected for different species. Additionally, the Automatic Barcode Gap Discovery method and the Bayesian implementation of the Poisson tree processes were carried out with COI sequences to explore species limits, and their results were consistent with ML analyses. In summary, the results obtained showed that there are no morphological or molecular differences between these nominal species of the valid skate genus Zearaja, leading to the conclusion that they are conspecific. Therefore, we designated Z. brevicaudata as a senior synonym of D. lamillai.

Elucidating species diversity of genus Betta from Aceh waters Indonesia using morphometric and genetic data

Species of the genus Betta are very similar morphologically which could lead to inaccuracy in taxonomic identification. Therefore, morphological data should also be complemented with other approaches such as genetics to validate the taxonomic status of member species. The objective of this study was to validate the taxonomic status of the genus Betta from Aceh waters using morphometric and genetic data. Sampling was conducted from January to September 2020 at 12 locations within Aceh province. Based on initial assessment identification of morphology, there were four presumed species of Betta in Aceh waters, namely; Betta rubra, Betta dennisyongi, Betta splendens, Betta imbellis. A total of 50 samples from each presumed species were assessed for traditional and truss morphometric analysis, while 5 specimens were randomly selected from each morphospecies for genetic analysis based on the cytochrome oxidase subunit I (COI) gene. The traditional morphometric data divided the four Betta species into two group with B. rubra and B. dennisyongi in same group (group I), while B. splendens and B. imbellis in different group (group II). While, the truss morphometric data divided the four Betta species into three groups with B. rubra and B. dennisyongi in group 1, B. splendens in group 2, while B. imbellis form the other group. The head depth of the fishes was an important characteristic to distinguish members of the four species. In parallel, the genetic analysis supported the occurrence of four valid species with intraspecific values of 0.0–1.59% and interspecific values ranging from 3.3 to 24.7%, the same clustering relationship as in the morphometric data. While B. rubra, B. splendens, and B. imbellis sequences are already available in GenBank, this study reports the first record of B. dennisyongi COI sequences.