Nuclear 18S rRNA Gene Research Articles

An endemic freshwater mussel species from the Orontes River basin in Turkey and Syria represents duck mussel’s intraspecific lineage: Implications for conservation

Amik Lake or, historically, Lake of Antioch, was a large freshwater body in the lower Orontes River basin (Hatay Province, Turkey) that was drained in the 1940s–1970s. Several endemic animal species were described from this lake, including the freshwater mussel Anodonta pseudodopsisLocard, 1883 (Bivalvia: Unionidae) characterized by a large rounded shell covered by a peculiar yellow or yellowish-brown periostracum. Molecular analyses of topotypes of this nominal taxon collected from the former lake’s tributaries in the Amik Plain indicate that it is an intra-specific lineage of the widespread Anodonta anatina (Linnaeus, 1758) based on the mitochondrial COI and 16S rRNA, and the nuclear 28S rRNA gene fragments. Geometric morphometric analyses using the lectotype and topotypes of Anodonta pseudodopsis support our DNA-based hypothesis on the status of this nominal taxon. A new synonymy is provided as follows: Anodonta anatina = Anodonta pseudodopsissyn. nov. The syntype of Anodonta pseudodopsis SMF 5129 “See von Antiochia” (Senckenberg Research Institute and Natural History Museum, Frankfurt, Germany) is designated here to be the lectotype of this nominal taxon. Finally, we conclude that Anodonta anatina range covers the Orontes River basin in Turkey and Syria and the Nahr al-Kabir al-Shamali River in the Latakia Governorate of Syria. This intraspecific lineage of Anodonta anatina and other freshwater mussels of the Middle East are highly threatened due to multiple anthropogenic impacts and must be a focus of international conservation efforts. The Karasu River in eastern Turkey hosts viable populations of all freshwater mussel species of the Orontes’s fauna and can be considered one of the most important water bodies for the conservation of these imperiled animals in the region.

Taxonomic Reappraisal of Lineus longifissus Auct. (Nemertea: Pilidiophora) from Japan for the First Time in 122 Years.

Having been reported in 1898 for the first time from Japanese waters, the lineid heteronemertean Lineus longifissus auct. is known to inhabit tidal flats under the influence of the warm Kuroshio Current along the coasts of Honshu and southwestward, characteristically with a uniformly raisin-colored to black body lacking a caudal cirrus. The taxonomic identity of the Japanese L. longifissus auct. has been questioned by specialists because of some obvious morphological differences between Lineus longifissus (Hubrecht, 1887) s.str. (now in Heteronemertes Chernyshev, 1995), originally described from the subantarctic region. In the present study, we describe the Japanese L. longifissus auct. as Corsoua takakurai sp. nov. Before the present study, the genus Corsoua Corrêa, 1963 had been monotypic with the type species Corsoua kristenseni Corrêa, 1963 from the Caribbean. We infer the phylogenetic position of Corsoua takakurai within Lineidae based on the mitochondrial 16S rRNA and cytochrome c oxidase subunit I, and the nuclear 18S rRNA, 28S rRNA, and histone H3 genes.

Redescription of Cerebratulus marginatus auct. (Nemertea: Pilidiophora) from Hokkaido, Japan, as a new species.

The heteronemertean Cerebratulus orochi sp. nov. is described based on material collected intertidally at a muddy beach in Akkeshi, northern Japan. For the last 80 years, the species has been confused with Cerebratulus marginatus Renier, 1804; the latter was originally described from the Adriatic and once believed to occur in many places in the northern hemisphere including Japan. Cerebratulus orochi sp. nov. is morphologically different from all the congeners including C. marginatus by the following combination of characters: several layers of diagonal-muscle meshwork coated with connective tissue, proximo-distally distributed in cross section from the distal portion of the body-wall outer longitudinal muscle layer to the cutis-gland zone throughout the anterior portion of the body from the precerebral to the foregut regions; the cephalic vascular system consisting of lateral and mid-dorsal vessels; and the sub-rhynchocoelic vessel possessing a pair of antero-lateral diverticula before the former forks posteriorly into a pair of lower lateral vessels in the post-cerebral, pre-oral region. Previous records of C. marginatus from Japanese waters are no longer considered to be substantiated. Multi-locus phylogenetic analyses based on the mitochondrial 16S rRNA and cytochrome c oxidase subunit I (COI), as well as the nuclear 18S rRNA, 28S rRNA, and histone H3 genes among heteronemerteans comprising the "Cerebratulus clade" indicated that C. orochi sp. nov. was closely related to C. cf. marginatus from the US Pacific coast. A MegaBLAST search at the NCBI website with the 16S rRNA gene sequence from C. orochi sp. nov. followed by a couple of species delimitation analyses suggests that larvae of the species are also distributed in Vostok Bay, Far East Russia.

Lacydoniidae (Annelida) Off the Coast of North-eastern Japan: A Description of Lacydonia japonica sp. nov.

Lacydonia japonica sp. nov. (Annelida, Lacydoniidae) is described based on material found in sediments collected off the Pacific coast of northern Honshu, Japan, at depths of 262 m and 407 m. The sediments were obtained by a remotely operated vehicle equipped with a suction sampler during a Tohoku Ecosystem-Associated Marine Sciences (TEAMS) project in 2019. Lacydonia japonica sp. nov. belongs to the eyeless group of lacydoniids and is discriminated from the morphologically most similar congener, Lacydonia papillata Uschakov, 1958 by its reddish pigments on both the dorsal and ventral parapodial cirri and four pigment spots on the pygidium. To assess the phylogenetic position of the new species among other lacydoniids for which sequence data are available in public databases, analyses were performed using the mitochondrial cytochrome c oxidase subunit I (COI) and 16S rRNA, as well as the nuclear 18S rRNA and 28S rRNA genes. We additionally obtained some lacydoniids by sledging off western Japan, but these were severely fragmented and broken during collection. Using the paucity of morphological data, they were left unidentified as Lacydonia sp. but included in the molecular analyses. Genetic distances between Lacydonia eliasoni Hartmann-Schröder, 1996, Lacydonia japonica, and Lacydonia sp. off western Japan were 10.4-17.1% uncorrected p-distance (11.3-18.6% K2P) in terms of 658-bp COI sequences.

Description of Sarcocystis scandentiborneensis sp. nov. from treeshrews (Tupaia minor, T. tana) in northern Borneo with annotations on the utility of COI and 18S rDNA sequences for species delineation.

Sarcocystis scandentiborneensis sp. nov. was discovered in histological sections of striated musculature of treeshrews (Tupaia minor, T. tana) from Northern Borneo. Sarcocysts were cigar-shaped, 102 μm–545 μm long, and on average 53 μm in diameter. The striated cyst wall varied in thickness (2–10 μm), depending on whether the finger-like, villous protrusions (VP) were bent. Ultrastructurally, sarcocysts were similar to wall type 12 but basal microtubules extended into VPs that tapered off with a unique U-shaped, electron-dense apical structure. In phylogenetic trees of the nuclear 18S rRNA gene, S. scandentiborneensis formed a distinct branch within a monophyletic subclade of Sarcocystis spp. with (colubrid) snake-rodent life cycle. We mapped all intraspecific (two haplotypes) and interspecific nucleotide substitutions to the secondary structure of the 18S rRNA gene: in both cases, the highest variability occurred within helices V2 and V4 but intraspecific variability mostly related to transitions, while transition/transversion ratios between S. scandentiborneensis, S. zuoi, and S. clethrionomyelaphis were skewed towards transversions. Lack of relevant sequences restricted phylogenetic analysis of the mitochondrial Cytochrome C oxidase subunit I (COI) gene to include only one species of Sarcocystis recovered from a snake host (S. pantherophisi) with which the new species formed a sister relationship. We confirm the presence of the functionally important elements of the COI barcode amino acid sequence of S. scandentiborneensis, whereby the frequency of functionally important amino acids (Alanine, Serine) was markedly different to other taxa of the Sarcocystidae. We regard S. scandentiborneensis a new species, highlighting that structurally or functionally important aspects of the 18S rRNA and COI could expand their utility for delineation of species. We also address the question why treeshrews, believed to be close to primates, carry a parasite that is genetically close to a Sarcocystis lineage preferably developing in the Rodentia as intermediate hosts.

Species, Sequence Types and Alleles: Dissecting Genetic Variation in Acanthamoeba.

Species designations within Acanthamoeba are problematic because of pleomorphic morphology. Molecular approaches, including DNA sequencing, hinted at a resolution that has yet to be fully achieved. Alternative approaches were required. In 1996, the Byers/Fuerst lab introduced the concept of sequence types. Differences between isolates of Acanthamoeba could be quantitatively assessed by comparing sequences of the nuclear 18S rRNA gene, ultimately producing 22 sequence types, designated T1 through T22. The concept of sequence types helps our understanding of Acanthamoeba evolution. Nevertheless, substantial variation in the 18S rRNA gene differentiates many isolates within each sequence type. Because the majority of isolates with sequences in the international DNA databases have been studied for only a small segment of the gene, designated ASA.S1, genetic variation within this hypervariable region of the 18S rRNA gene has been scrutinized. In 2002, we first categorized variation in this region in a sample of T3 and T4 isolates from Hong Kong, observing ten “alleles” within type T4 and five “alleles” within T3. Subsequently, confusion occurred when different labs applied redundant numerical labels to identify different alleles. A more unified approach was required. We have tabulated alleles occurring in the sequences submitted to the international DNA databases, and determined their frequencies. Over 150 alleles have occurred more than once within 3500+ isolates of sequence type T4. Results from smaller samples of other sequence types (T3, T5, T11 and T15, and supergroup T2/6) have also been obtained. Our results provide new insights into the evolutionary history of Acanthamoeba, further illuminating the degree of genetic separation between significant taxonomic units within the genus, perhaps eventually elucidating what constitutes a species of Acanthamoeba.

Seasonal Filarial Infections and Their Black Fly Vectors in Chiang Mai Province, Northern Thailand.

The transmission of zoonotic filarial parasites by black flies has so far been reported in the Chiang Mai and Tak provinces, Thailand, and the bites of these infected black flies can cause a rare disease—human zoonotic onchocerciasis. However, species identification of the filarial parasites and their black fly vectors in the Chiang Mai province were previously only based on a morphotaxonomic analysis. In this study, a combined approach of morphotaxonomic and molecular analyses (mitochondrial cox1, 12S rRNA, and nuclear 18S rRNA (SSU HVR-I) genes) was used to clarify the natural filarial infections in female black flies collected by using human and swine baits from two study areas (Ban Lek and Ban Pang Dang) in the Chiang Mai province from March 2018 to January 2019. A total of 805 and 4597 adult females, belonging to seven and nine black fly taxa, were collected from Ban Lek and Ban Pang Dang, respectively. At Ban Lek, four of the 309 adult females of Simulium nigrogilvum were positive for Onchocerca species type I in the hot and rainy seasons. At Ban Pang Dang, five unknown filarial larvae (belonging to the same new species) were detected in Simulium sp. in the S. varicorne species-group and in three species in the S. asakoae species-group in all seasons, and three non-filarial larvae of three different taxa were also found in three females of the S. asakoae species-group. This study is the first to molecularly identify new filarial species and their vector black fly species in Thailand.

Crenosoma Striatum in Lungs of European Hedgehogs (Erinaceus Europeus) from Portugal.

SummaryCrenosoma striatum is a host-specifi c metastrongiloid nematode causing respiratory tract disease in hedgehogs (Erinaceus europaeus). Since few studies have reported C. striatum in hedgehogs and little genetic data is available concerning this lungworm, this study aimed to determine the occurrence of C. striatum in a population sample of hedgehogs from Portugal, additionally providing morphological, histological and molecular data. From 2017 to 2018 a survey of infection was carried out in 11 necropsied hedgehogs. Worms were extracted from fresh lung tissues and microscopically evaluated. Molecular characterization of partial mitochondrial (12S rRNA) and nuclear (18S rRNA) genes was performed. The presence of lungworms in pulmonary tissues of five hedgehogs (45.5%) was detected. Morphological and histopathological analyses evidenced adult forms of nematodes consistent with C. striatum. Molecular characterization of 18S rRNA genes confirmed the classifi cation as C. striatum. Also, novel genetic data characterizing the mitochondrial (12S rRNA) gene of C. striatum is presented.This is the first report of C. striatum infection in hedgehogs of Portugal. The findings here reported provide new insights regarding the geographic distribution and the molecular identification of this lungworm species.

New dicrocoeliid digeneans from mammals in Ecuador including a highly genetically divergent new genus from an ancient marsupial lineage.

The Dicrocoeliidae is a highly diverse and broadly distributed family of digeneans typically parasitic in the gall bladder and liver of their tetrapod hosts. So far, no study has reported dicrocoeliids, or any digeneans, from the ancient marsupial family Caenolestidae. Herein, we describe a new genus of dicrocoeliids (Otongatrema n. gen.) from Tate's shrew opossum Caenolestes fuliginosus and a new species of Metadelphis (Metadelphis cesartapiai n. sp.) from a phyllostomid bat Anoura peruana collected in Ecuador. Otongatrema can be readily distinguished from the morphologically closest dicrocoeliid genera Concinnum, Conspicuum and Canaania based on the position of the genital pore, distribution/position of the uterus and extent of vitellarium. Metadelphis cesartapiai can be easily differentiated from other Metadelphis spp. based on a combination of morphological characters including body shape and size, distribution of vitellarium, shape of the gonads as well as size of suckers and cirrus sac. In addition, we used newly generated partial sequences of the nuclear 28S rRNA gene and mitochondrial cox1 genes to examine phylogenetic affinities of the new taxa within the Dicrocoeliidae. Both the 28S and cox1 phylogenies confidently positioned Otongatrema as a sister/basal group to all other dicrocoeliids sequenced so far. The phylogenetic position of Otongatrema may be explained by a close co-evolutionary relationship with Caenolestidae, one of the most basal and most ancient groups of marsupials. In addition, our 28S phylogeny provides evidence that the complete or partial loss of intestinal structures has likely occurred independently at least 3 times in the evolutionary history of the Dicrocoeliidae.

Evolutionary relationships among Massospora spp. (Entomophthorales), obligate pathogens of cicadas

ABSTRACT The fungal genus Massospora (Zoopagomycota: Entomophthorales) includes more than a dozen obligate, sexually transmissible pathogenic species that infect cicadas (Hemiptera) worldwide. At least two species are known to produce psychoactive compounds during infection, which has garnered considerable interest for this enigmatic genus. As with many Entomophthorales, the evolutionary relationships and host associations of Massospora spp. are not well understood. The acquisition of M. diceroproctae from Arizona, M. tettigatis from Chile, and M. platypediae from California and Colorado provided an opportunity to conduct molecular phylogenetic analyses and morphological studies to investigate whether these fungi represent a monophyletic group and delimit species boundaries. In a three-locus phylogenetic analysis including the D1–D2 domains of the nuclear 28S rRNA gene (28S), elongation factor 1 alpha-like (EFL), and beta-tubulin (BTUB), Massospora was resolved in a strongly supported monophyletic group containing four well-supported genealogically exclusive lineages, based on two of three methods of phylogenetic inference. There was incongruence among the single-gene trees: two methods of phylogenetic inference recovered trees with either the same topology as the three-gene concatenated tree (EFL) or a basal polytomy (28S, BTUB). Massospora levispora and M. platypediae isolates formed a single lineage in all analyses and are synonymized here as M. levispora. Massospora diceroproctae was sister to M. cicadina in all three single-gene trees and on an extremely long branch relative to the other Massospora, and even the outgroup taxa, which may reflect an accelerated rate of molecular evolution and/or incomplete taxon sampling. The results of the morphological study presented here indicate that spore measurements may not be phylogenetically or diagnostically informative. Despite recent advances in understanding the ecology of Massospora, much about its host range and diversity remains unexplored. The emerging phylogenetic framework can provide a foundation for exploring coevolutionary relationships with cicada hosts and the evolution of behavior-altering compounds.

Uncharted digenean diversity in Lake Tanganyika: cryptogonimids (Digenea: Cryptogonimidae) infecting endemic lates perches (Actinopterygii: Latidae)

BackgroundLake Tanganyika is considered a biodiversity hotspot with exceptional species richness and level of endemism. Given the global importance of the lake in the field of evolutionary biology, the understudied status of its parasite fauna is surprising with a single digenean species reported to date. Although the most famous group within the lake’s fish fauna are cichlids, the pelagic zone is occupied mainly by endemic species of clupeids (Actinopterygii: Clupeidae) and lates perches (Actinopterygii: Latidae, Lates Cuvier), which are an important commercial source for local fisheries. In this study, we focused on the lake’s four lates perches and targeted their thus far unexplored endoparasitic digenean fauna.MethodsA total of 85 lates perches from four localities in Lake Tanganyika were examined. Cryptogonimid digeneans were studied by means of morphological and molecular characterisation. Partial sequences of the nuclear 28S rRNA gene and the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene were sequenced for a representative subset of the specimens recovered. Phylogenetic analyses were conducted at the family level under Bayesian inference.ResultsOur integrative approach revealed the presence of six species within the family Cryptogonimidae Ward, 1917. Three out of the four species of Lates were found to be infected with at least one cryptogonimid species. Two out of the three reported genera are new to science. Low interspecific but high intraspecific phenotypic and genetic diversity was found among Neocladocystis spp. Phylogenetic inference based on partial 28S rDNA sequences revealed a sister group relationship for two of the newly erected genera and their close relatedness to the widely distributed genus Acanthostomum Looss, 1899.ConclusionsThe present study provides the first comprehensive characterisation of the digenean diversity in a fish family from Lake Tanganyika which will serve as a baseline for future explorations of the lake’s digenean fauna. Our study highlights the importance of employing an integrative approach for revealing the diversity in this unique host-parasite system.

Deep-sea corals provide new insight into the ecology, evolution, and the role of plastids in widespread apicomplexan symbionts of anthozoans

BackgroundApicomplexans are the causative agents of major human diseases such as malaria and toxoplasmosis. A novel group of apicomplexans, recently named corallicolids, have been detected in corals inhabiting tropical shallow reefs. These apicomplexans may represent a transitional lifestyle between free-living phototrophs and obligate parasites. To shed light on the evolutionary history of apicomplexans and to investigate their ecology in association with corals, we screened scleractinians, antipatharians, alcyonaceans, and zoantharians from shallow, mesophotic, and deep-sea communities. We detected corallicolid plastids using 16S metabarcoding, sequenced the nuclear 18S rRNA gene of corallicolids from selected samples, assembled and annotated the plastid and mitochondrial genomes from a corallicolid that associates with a deep-sea coral, and screened the metagenomes of four coral species for corallicolids.ResultsWe detected 23 corallicolid plastotypes that were associated with 14 coral species from three orders and depths down to 1400 m. Individual plastotypes were restricted to coral hosts within a single depth zone and within a single taxonomic order of corals. Some clusters of closely related corallicolids were revealed that associated with closely related coral species. However, the presence of divergent corallicolid lineages that associated with similar coral species and depths suggests that corallicolid/coral relations are flexible over evolutionary timescales and that a large diversity of apicomplexans may remain undiscovered. The corallicolid plastid genome from a deep-sea coral contained four genes involved in chlorophyll biosynthesis: the three genes of the LIPOR complex and acsF.ConclusionsThe presence of corallicolid apicomplexans in corals below the photic zone demonstrates that they are not restricted to shallow-water reefs and are more general anthozoan symbionts. The presence of LIPOR genes in the deep-sea corallicolid precludes a role involving photosynthesis and suggests they may be involved in a different function. Thus, these genes may represent another set of genetic tools whose function was adapted from photosynthesis as the ancestors of apicomplexans evolved towards parasitic lifestyles.F2zJxksEL9EUf83G36J_vHVideo abstract

Small-scale spatial variation of meiofaunal communities in Lima estuary (NW Portugal) assessed through metabarcoding

Meiofaunal organisms play a key role in estuarine ecosystems, being responsible for significant ecological processes. However, meiofauna constitutes a particularly difficult community to be monitored through conventional morphology-based approaches. New emerging tools, such as DNA metabarcoding, facilitate the access to these communities and provide an opportunity to develop routine monitoring programs. In the present study, the small-scale spatial variation of meiofaunal communities in the Lima estuary (NW Portugal) was investigated using DNA metabarcoding. The first stage of the study aimed to establish the amount of sediment sample to be used for DNA extraction and to test six primer pairs, three of them amplifying fragments from the mitochondrial cytochrome c oxidase gene (COI) and three other the nuclear ribosomal 18S rRNA gene (18S). In a subsequent stage, sediment samples were collected in four stations along an estuarine gradient (salinity ranging between 9 and 28), in which six sampling points about 4–5 m apart were considered: three in the high intertidal and three in the mid intertidal. After the DNA extraction from sediments, COI and 18S amplicon libraries were produced and sequenced in an Illumina MiSeq platform. OTUs (operational taxonomic units) recovered by either COI or 18S displayed generally high turnover in occurrence among sampling points within a station and tidal horizon, among tidal horizons within a station, and among stations of distinct salinity (approx. 60–93%). Both markers recorded little variation among stations in OTU richness and in the taxonomic composition of the most dominant groups. However, the meiofauna detected differed qualitatively between the two markers used; Amoebozoa and Cnidaria were mostly detected with COI while Ciliophora and Platyhelminthes with 18S. In addition, the structure of the meiofauna community diverged significantly among stations and was strongly influenced by salinity and sediment features. Globally, results indicated a highly patchy distribution of meiofauna taxa in the Lima estuary, revealed by the high OTU turnover even between sampling points only a few meters apart. Hence, eDNA-based meiofauna surveys require consideration of the necessary sampling effort on relatively small spatial scales, as well as an appreciation of the tidal level-induced variation of these communities.

Phylogenetic relationships of the bacchine flower flies (Diptera: Syrphidae) based on molecular characters, with a description of a new species of Melanostoma (Schiner, 1860)

The phylogenetic relationships among the genera of the tribe Bacchini sensu lato (i.e., Syrphinae with simple, unsegmented aedeagus) were inferred using molecular evidence. The mitochondrial protein-coding gene cytochrome c oxidase subunit I (COI) and the nuclear ribosomal 28S and 18S rRNA genes for 54 bacchine taxa were analyzed using Bayesian inference and Maximum Likelihood. Among the analyzed taxa there is a new species of Melanostoma (Schiner) from Cameroon, Melanostoma janeceki Mengual, sp. nov., which is described in full. This new species has a complete metasternum without excavation, a characteristic that is not present in other species of Melanostoma, usually with an excavated metasternum, but it is the diagnostic character of the genus Afrostoma Skevington, Thompson & Vockeroth. Based on the phylogenetic placement of Melanostoma janeceki Mengual, sp. nov. the taxonomic status of Afrostoma as a genus is discussed and a new generic classification of Bacchini stat. rev. and Melanostomini stat. rev. is presented in the light of the inferred phylogeny. Results did not recover Bacchini sensu lato monophyletic, but into two groups as follows: Melanostoma and related genera, and Baccha, Platycheirus and related genera. Pseudoplatychirus van Doesburg is considered junior synonym of Platycheirus Le Peletier & Audinet-Serville, and Afrostoma Skevington, Thompson & Vockeroth as junior synonym of Melanostoma. Pyrophaena Schiner and Eocheilosia Hull comb. nov. are ranked as valid genera, and consequently, the genus Platycheirus is divided into four subgenera: Platycheirus (Carposcalis) (Enderlein), Platycheirus (Pachysphyria) (Enderlein), Platycheirus (Platycheirus), and Platycheirus (Tuberculanostoma) (Fluke) comb. nov.

First genetic record of the non-native muzzled blenny Omobranchus punctatus (Teleostei: Blenniidae) in the Atlantic Coast of Central and South America.

In this study we sequenced two mitochondrial (COI and 16S rRNA) and one nuclear (18S rRNA) gene fragment of an introduced muzzled blenny (Omobranchus punctatus) specimen collected from the Orinoco Delta (Gulf of Paria estuary) in Venezuela. This is the first genetic data generated for this species' introduced range in Central and South America, suggesting an introduction from the Indian Ocean.

Integrative taxonomy reveals new taxa of Trochidae (Gastropoda: Vetigastropoda) from seamounts in the tropical western Pacific

During two expeditions to seamounts near the Mariana Trench in the tropical western Pacific, several trochiform shells from the upper bathyal zone were sampled. Morphological observations of these specimens suggest that they represent two new species that belong to the family Trochidae, but the shell morphology, radular plan, and external anatomy differ considerably from those of closely related genera. A new subfamily, Carinotrochinae subfam. nov., and a new genus, Carinotrochus gen. nov., are proposed herein to accommodate these two species. Carinotrochus marianaensis sp. nov., the type species, was associated with coral debris at a depth of 865 m, and Carinotrochus williamsae sp. nov. was discovered crawling on a hydroid Stegolaria sp. that was attached to a dead bamboo coral at a depth of 1332 m. Genertic analysis of mitochondrial COI, 16S rRNA, and nuclear 28S rRNA genes using maximum likelihood, Bayesian inference, and pairwise uncorrected p-distances confirmed that the new taxa are trochids but do not belong to any existing defined subfamily. Molecular clock analysis based on concatenated sequences (COI, 16S, and 28S) indicated that Carinotrochinae subfam. nov. split from its shallow water sister subfamily Trochinae roughly 80 Mya during the Late Cretaceous.

Revision of the Merodon serrulatus group (Diptera, Syrphidae).

The phytophagous hoverfly genus Merodon Meigen, 1803 (Diptera, Syrphidae), which comprises more than 160 species distributed in Palaearctic and Afrotropical regions, can be differentiated into multiple groups of species that harbor high levels of hidden diversity. In this work, the serrulatus species group of Merodon is revised, providing an illustrated key to species, a detailed discussion on the taxonomic characters and a morphological diagnosis, including also the first data about the preimaginal morphology of this species group. The study includes characteristics of the 13 species of the M. serrulatus group, along with the available distributional data. Moreover, descriptions are provided for seven new species, namely M. defectus Vujić, Likov & Radenković sp. nov., M. disjunctus Vujić, Likov & Radenković sp. nov., M. medium Vujić, Likov & Radenković sp. nov., M. nigrocapillatus Vujić, Likov & Radenković sp. nov., M. nigropunctum Vujić, Likov & Radenković sp. nov., M. opacus Vujić, Likov & Radenković sp. nov., and M. trianguloculus Vujić, Likov & Radenković sp. nov. In addition, the taxa M. serrulatus (Wiedemann in Meigen, 1822), M. bequaerti Hurkmans, 1993, M. hirsutus Sack, 1913, M. kawamurae Matsumura, 1916, M. sacki (Paramonov, 1936) and M. sophron Hurkmans, 1993 are redefined and redescribed. Following a detailed study of the type material sourced from different entomological collections, the status of all available taxa related to M. serrulatus is revised and a new synonymy is proposed: M. tener Sack, 1913 syn. nov. (junior synonym of M. serrulatus). The identity of M. trizonus (Szilády, 1940) could not be assessed as the type specimens are lost. Thus, the name M. trizonus is considered as nomen dubium. The monophyly and composition of this species group are assessed through Maximum Parsimony and Maximum Likelihood analyses of the mitochondrial COI and nuclear 28S rRNA gene sequences.

On the taxonomic position of Phaenomenella Fraussen & Hadorn, 2006 (Neogastropoda, Buccinoidea) with description of two new species

This contribution provides novel information on the anatomy, radula and phylogeny of several species of PhaenomenellaFraussen & Hadorn, 2006, a genus of Buccinoidea Rafinesque, 1815 with unclear affinities. Molecular phylogenetic analysis based on sequences of mitochondrial COI and nuclear 28S rRNA genes of different representatives of Buccinoidea revealed close relationships of Phaenomenella with Siphonalia A. Adams, 1863 both taxa forming a clade with maximal support. The anatomy of two species of the latter genus was examined for the first time for comparative purposes. The subfamily Siphonaliinae Finlay, 1928 was erected for several Recent and fossil genera of Southern Hemisphere Buccinidae Rafinesque, 1815, and is still recognized by current taxonomists (Bouchet et al. 2017). Species of all Recent genera of Siphonaliinae were included in our analysis and the monophyly of the subfamily Siphonaliinae in its original scope is rejected. Molecular and morphological data revealed two still unnamed species of Phaenomenella from the lower bathyal zone of the South China Sea. These species, Phaenomenella nicoi n. sp. and P. samadiae n. sp. are described in the present study.

Distribution, genetic characteristics and public health implications of Triatoma rubrofasciata, the vector of Chagas disease in Guangxi, China

BackgroundTriatomines are natural vectors of Chagas disease and are mainly prevalent in the Americas. In China, previous data from decades ago showed that there were two species of triatomine bugs, Triatoma rubrofasciata and T. sinica. However, the distribution, genetic characteristics and public health implications of triatomines in China are still relatively unknown. In order to gain knowledge on the distribution, genetic characteristics and public health implications of the triatomines in Guangxi, China, an entomological-epidemiological study and genetic research was conducted.MethodsDifferent methods were used to elucidate the distribution of triatomines in Guangxi including consultations with county-level Center for Disease Prevention and Control staff and village doctors, the distribution of educational material on triatomines though the internet and social media apps such as Wechat and QQ, and conducting manual inspections and light trapping to collect triatomines. The morphological characteristics of the collected triatomines were identified under light microscopy. The mitochondrial 16S rRNA, cytochrome b (cytb) genes and nuclear 28S rRNA gene were amplified, sequenced and used in phylogenetic analyses.ResultsA total of 305 triatomines were captured from 54 different sites in 13 cities in Guangxi. All collected bugs were identified as T. rubrofasciata based on morphology. Most triatomine collection sites were around or inside houses. Four triatomines bite cases were observed during the investigation indicating that triatomine bites are common, the bites can cause serious anaphylaxis and skin papules and urticaria, suggesting a systemic skin response. The 16S rRNA, 28S rRNA and cytb sequence analyses of T. rubrofasciata from Guangxi and other countries showed that T. rubrofasciata sequences from different regions exhibit a high similarity, with no geographical differences. The phylogenetic tree based on the 16S rRNA and cytb genes showed that T. rubrofasciata sequences from different regions and continents were in the same cluster, indicating no differentiation among different geographical populations.ConclusionsOur study showed that T. rubrofasciata is widely distributed in Guangxi and that people are commonly bitten by this insect in some regions. This highlights the need to enhance surveillance for and control of T. rubrofasciata and to strengthen the monitoring of imported Trypanosoma cruzi in China. The 16S rRNA, 28S rRNA and cytb sequence analyses of T. rubrofasciata from different regions and continents suggested that T. rubrofasciata populations exhibit high similarity, and the clustering in the phylogenetic analyses indicates that T. rubrofasciata has a close ancestor originating in the Americas.

Phyllodistomum vaili(Plagiorchiida: Gorgoderidae) infecting Parupeneus rubescens (Perciformes: Mullidae): morphology and phylogeny.

Knowledge of the Arabian Gulf fish's parasite fauna is very poor. Until recently, only scattered reports from different locations are known for ecto- and endoparasites. Therefore, the present study aimed to investigate the digenean species that infects one of the most economically fish species in the Arabian Gulf, the rosy goatfish Parupeneus rubescens . One plagiorchiid species has been described, belonging to the Gorgoderidae family, and has been named as Phyllodistomum vaili Ho, Bray, Cutmore, Ward & Cribb, 2014 based on its morphological and morphometric characteristics. In order to accurately classify and characterize this plagiorchiid species, molecular analysis was carried out using both nuclear 18S and 28S rRNA gene regions and revealed that the present plagiorchiid species was associated with other species belonging to the Gorgoderidae family and deeply embedded in the Phyllodistomum genus, closely related to the previously described P. vaili (gb| KF013187.1, KF013173.1). The present study therefore revealed that the species Phyllodistomum is the first account as endoparasites from the rosy goatfish inhabiting the Arabian Gulf.