Molecular divergence between two sympatric species of Dondice (Mollusca: Nudibranchia) with distinct feeding specializations

2013 ◽  
Vol 93 (7) ◽  
pp. 1887-1893 ◽  
Author(s):  
Luis Gonzalez ◽  
Dieta Hanson ◽  
Ángel Valdés
Keyword(s):  
Feeding Habits ◽  
Phylogenetic Analyses ◽  
Molecular Data ◽  
Sympatric Species ◽  
Developmental Differences ◽  
Nominal Species ◽  
Western Atlantic ◽  
16S Gene ◽  
Putative Species ◽  
Gene Data

Analysis of mitochondrial (16S) and nuclear (H3) gene data using phylogenetic and population genetic approaches has revealed some genetic differences between two putative species of western Atlantic Dondice opisthobranchs that feed differentially on hydroids or on up-side-down jellies of the genus Cassiopeia. These results partially support the validity of the species Dondice parguerensis, which was described for the jelly-eating Dondice. However, phylogenetic analyses revealed that the hydroid-feeding species Dondice occidentalis and D. parguerensis are not reciprocally monophyletic and they are identical for the nuclear H3 gene. Although there are morphological and developmental differences between these two nominal species, the molecular data are inconclusive. A possible explanation is that the two putative species are in the process of speciation due to different feeding habits, resulting in the presence of genetic synapomorphies in D. parguerensis, but only in the more variable 16S gene. Because the ranges D. occidentalis and D. parguerensis overlap and there are no obvious barriers to gene flow between the two putative species, this may constitute a possible example of incipient sympatric speciation in benthic marine organisms.

High cryptic diversity in the kleptoparasitic genus Hyalorisia Dall, 1889 (Littorinimorpha: Capulidae) with the description of nine new species from the Indo-West Pacific

2020 ◽  
Vol 86 (4) ◽  
pp. 401-421 ◽  
Author(s):  
Giulia Fassio ◽  
Valeria Russini ◽  
Barbara Buge ◽  
Stefano Schiaparelli ◽  
Maria Vittoria Modica ◽  
...  
Keyword(s):  
Trophic Ecology ◽  
Molecular Data ◽  
Sympatric Species ◽  
Water Current ◽  
Phylogenetic Position ◽  
Nominal Species ◽  
West Pacific ◽  
Allopatric Species ◽  
Wide Range ◽  
The Family

ABSTRACT Species in the family Capulidae (Littorinimorpha: Capuloidea) display a wide range of shell morphologies. Several species are known to live in association with other benthic invertebrates—mostly bivalves and sabellid worms, but also other gastropods—and are believed to be kleptoparasitic filter feeders that take advantage of the water current produced by the host. This peculiar trophic ecology, implying a sedentary lifestyle, has resulted in highly convergent shell forms. This is particularly true for the genus Hyalorisia Dall, 1889, which occurs in deep water in the Caribbean and Indo-West Pacific provinces, with two nominal species recognized so far. Combining morphological, ecological and molecular data, we assessed the diversity of the genus, its phylogenetic position inside the family and its association with its bivalve host, the genus Propeamussium de Gregorio, 1884 (Pectinoidea), resulting in the description of nine new cryptic species. When sympatric, species of Hyalorisia are associated with different host species, but the same species of Propeamussium may be the host of several allopatric species of Hyalorisia.

scholarly journals Introducing Chaetothyriothecium, a new genus of Microthyriales

Phytotaxa ◽  
2014 ◽  
Vol 161 (2) ◽  
pp. 157 ◽  
Author(s):  
Sinang Hongsanan ◽  
Putarak Chomnunti ◽  
Pedro W. Crous ◽  
Ekachai Chukeatirote ◽  
Kevin D. Hyde
Keyword(s):  
New Genus ◽  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Molecular Data ◽  
Plant Host ◽  
Dna Sequence Data ◽  
Limited Sampling ◽  
Black Spots ◽  
Gene Data ◽  
Central Thailand

The order Microthyriales comprises foliar biotrophs, epiphytes, pathogens or saprobes that occur on plant leaves and stems. The order is relatively poorly known due to limited sampling and few in-depth studies. There is also a lack of phylogenetic data for these fungi, which form small black spots on plant host surfaces, but rarely cause any damage to the host. A "Microthyriaceae"-like fungus collected in central Thailand is described as a new genus, Chaetothyriothecium (type species Chaetothyriothecium elegans sp. nov.). Phylogenetic analyses of LSU gene data showed this species to cluster with other members of Microthyriales, where it is related to Microthyrium microscopicum the type of the order. The description of the new species is supplemented by DNA sequence data, which resolves its placement in the order. Little molecular data is available for this order, stressing the need for further collections and molecular data.

scholarly journals Annulatascus saprophyticus sp. nov. and Pseudoannulatascus gen. nov. to accommodate Annulatascus biatriisporus (Annulatascales, Sordariomycetes) from Thailand

Phytotaxa ◽  
2015 ◽  
Vol 239 (2) ◽  
pp. 174 ◽  
Author(s):  
Zonglong Luo ◽  
S.S.N MAHARACHCHIKUMBUR ◽  
Xiaoying Liu ◽  
Shuhong Li ◽  
Lijiao Chen ◽  
...  
Keyword(s):  
New Genus ◽  
Phylogenetic Analyses ◽  
Molecular Data ◽  
New Taxon ◽  
Northern Thailand ◽  
Gelatinous Matrix ◽  
Decaying Wood ◽  
Gene Data

A new Annulatascus species, A. saprophyticus, found on decaying wood in freshwater in northern Thailand is introduced in this paper. The new taxon is illustrated, described and compared with other species in the genus, as well as a key to genus is provided. It differs from other species in the genus in having straight up right necks at one end, paraphyses embedded in a gelatinous matrix, and 0–3-septate, fusoid to lunate ascospores, which are larger than other species in the genus. Phylogenetic analyses based on LSU gene data showed that A. saprophyticus belongs in Annulatascus sensu strict (Annulatascaceae, Annulatascales, Sordariomycetidae). Based on the molecular data and a reevaluation of morphology, a new genus Pseudoannulatascus in Annulatascaceae is introduced to accommodate Annulatascus biatriisporus.

Anchialine adjustments: an updated phylogeny and classification for the family Barbouriidae Christoffersen, 1987 (Decapoda: Caridea)

2020 ◽  
Vol 40 (4) ◽  
pp. 401-411 ◽  
Author(s):  
Robert E Ditter ◽  
Luis M Mejía-Ortíz ◽  
Heather D Bracken-Grissom
Keyword(s):  
Phylogenetic Analyses ◽  
Nuclear Gene ◽  
Morphological Characters ◽  
Molecular Data ◽  
Genetic Distances ◽  
Evolutionary Relationships ◽  
The Bahamas ◽  
16S Gene ◽  
Dichotomous Key ◽  
The Family

Abstract Barbouriidae Christoffersen, 1987 is a family comprised of 4 genera and 11 species of enigmatic shrimps restricted to anchialine or marine caves whose evolutionary history and relationships remain elusive. We investigated the evolutionary relationships among members of Barbouriidae with the inclusion of four genera and nine species, and newly collected material from Belize, the Bahamas, and the Yucatán Peninsula, Mexico. Phylogenetic analyses based on seven mitochondrial and nuclear gene regions and genetic distances calculated using partial 16S gene regions have identified a need to revisit the relationships and classification within Barbouriidae. More specifically, we find evidence to suggest Janicea Manning & Hart, 1984 as a junior synonym of Parhippolyte Borradaile, 1900, B. yanezi Mejía, Zarza & López, 2008 as a synonym of Barbouria cubensis (von Martens, 1872), and define two new subfamilies, Calliasmatinae Holthuis, 1973 and Barbouriinae Christoffersen, 1987. Included is a dichotomous key for the species of Barbouriidae that summarizes previous literature and includes new morphological characters. Our findings shed light on existing inaccuracies and gaps in molecular data from barbouriids. We also provide further clarity into evolutionary relationships among genera of Barbouriidae and their allies, suggesting phylogeographic divisions within the family. Our findings suggest an early Atlantic-Pacific divide among genera originating from a shallow-water reef ancestor.

Morphological description and molecular analyses of Tylodelphys sp. (Trematoda: Diplostomidae) newly recorded from the freshwater fish Gobiomorphus cotidianus (common bully) in New Zealand

2016 ◽  
Vol 91 (3) ◽  
pp. 332-345 ◽  
Author(s):  
I. Blasco-Costa ◽  
R. Poulin ◽  
B. Presswell
Keyword(s):  
New Zealand ◽  
Research Effort ◽  
Phylogenetic Analyses ◽  
Distinct Species ◽  
First Record ◽  
Molecular Data ◽  
Body Cavity ◽  
Morphological Description ◽  
Nominal Species ◽  
Gobiomorphus Cotidianus

AbstractAmong eyeflukes, Tylodelphys Diesing, 1850 includes diverse species able to infect the eyes, but also the brain, pericardial sac and body cavity of their second intermediate host. While the genus shows a cosmopolitan distribution with 29 nominal species in Africa, Asia, Europe and America, a likely lower research effort has produced two records only for all of Australasia. This study provides the first description of a species of Tylodelphys and the first record for a member of the Diplostomidae in New Zealand. Tylodephys sp. metacercaria from the eyes of Gobiomorphus cotidianus McDowall, 1975 is distinguished from its congeners as being larger in all, or nearly all, metrics than Tylodelphys clavata (von Nordmann, 1832), T. conifera (Mehlis, 1846) and T. scheuringi (Hughes, 1929); whereas T. podicipina Kozicka & Niewiadomska, 1960 is larger in body size, ventral sucker and holdfast sizes and T. ophthalmi (Pandey, 1970) has comparatively a very small pharynx and body spination. Tylodelphys sp. exhibits consistent genetic variation for the 28S rDNA, internal transcribed spacer (ITS) and Cox1 genes, and phylogenetic analyses confirm that it represents an independent lineage, closely related to North American species. Morphological and molecular results together support the distinct species status of Tylodephys sp. metacercaria, the formal description and naming of which await discovery of the adult. Furthermore, the validity of T. strigicola Odening, 1962 is restored, T. cerebralis Chakrabarti, 1968 is proposed as major synonym of T. ophthalmi, and species described solely on the basis of metacercariae are considered incertae sedis, except those for which molecular data already exist.

scholarly journals Cryptic and not-so-cryptic species in the complex Holothuria (Thymiosycia) impatiens (Forsskål, 1775) (Echinodermata: Holothuroidea)

2015 ◽  
Author(s):  
François Michonneau
Keyword(s):  
A Priori ◽  
Molecular Data ◽  
Integrative Approach ◽  
Input Tree ◽  
Species Limits ◽  
Western Atlantic ◽  
Test Species ◽  
Multispecies Coalescent ◽  
Putative Species ◽  
Coloration Patterns

Identifying accurately species is critical for our understanding of patterns of diversity and speciation. However, for many organisms with simple and variable morphological traits, the characters traditionally used by taxonomists to identify species might lead to a considerable under appreciation of their diversity. Recent advances in molecular-data based computational methods have considerably improved our ability to identify and test species limits. Here, we use an integrative approach to delineate species in a complex of sea cucumbers. We used a three-step approach to show thatHolothuria impatiens, a common, shallow-water species, occurring across the Indo-Pacific, the Western Atlantic and the Mediterranean Sea, targeted locally by fisheries, is a complex of at least 13 species. (1) We used the Generalized Mixed Yule Coalescent (GMYC) model to identify putative speciesa priorihypotheses. In the process, we also show that the number of putative species estimated with GMYC can be affected considerably by the priors used to build the input tree. (2) We assessed based on coloration patterns and distributional information, the most relevant hypothesis. This approach allowed us to identify unambiguously 9 species. However, some of the lineages consistently assigned to belong to different species using GMYC, are occurring in sympatry and are not differentiated morphologically. (3) We used Bayes factors to compare competing models of species assignment using the multispecies coalescent as implemented in *BEAST. This approach allowed us to validate that the species identified using GMYC were likely reproductively isolated. Estimates of the timing of diversification also showed that these species diverged less than 2 Ma, which is the fastest case of closely related species occurring in sympatry for a marine metazoan. Our study demonstrates how clarifying species limits contribute to refining our understanding of speciation.

scholarly journals Linking morphological and molecular sources to disentangle the case of Xylodon australis

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Javier Fernández-López ◽  
M. Teresa Telleria ◽  
Margarita Dueñas ◽  
Mara Laguna-Castro ◽  
Klaus Schliep ◽  
...  
Keyword(s):  
New Zealand ◽  
Phylogenetic Analyses ◽  
Single Species ◽  
R Package ◽  
Molecular Data ◽  
Historical Collections ◽  
Close Relationship ◽  
Kinship Relations ◽  
History Of ◽  
Different Sources

AbstractThe use of different sources of evidence has been recommended in order to conduct species delimitation analyses to solve taxonomic issues. In this study, we use a maximum likelihood framework to combine morphological and molecular traits to study the case of Xylodon australis (Hymenochaetales, Basidiomycota) using the locate.yeti function from the phytools R package. Xylodon australis has been considered a single species distributed across Australia, New Zealand and Patagonia. Multi-locus phylogenetic analyses were conducted to unmask the actual diversity under X. australis as well as the kinship relations respect their relatives. To assess the taxonomic position of each clade, locate.yeti function was used to locate in a molecular phylogeny the X. australis type material for which no molecular data was available using morphological continuous traits. Two different species were distinguished under the X. australis name, one from Australia–New Zealand and other from Patagonia. In addition, a close relationship with Xylodon lenis, a species from the South East of Asia, was confirmed for the Patagonian clade. We discuss the implications of our results for the biogeographical history of this genus and we evaluate the potential of this method to be used with historical collections for which molecular data is not available.

scholarly journals The Complete DNA Sequence of the Mitochondrial Genome of a “Living Fossil,” the Coelacanth (Latimeria chalumnae)

Genetics ◽  
1997 ◽  
Vol 146 (3) ◽  
pp. 995-1010 ◽  
Author(s):  
Rafael Zardoya ◽  
Axel Meyer
Keyword(s):  
Mitochondrial Genome ◽  
Tandem Repeats ◽  
Phylogenetic Analyses ◽  
Large Data ◽  
Molecular Data ◽  
Phylogenetic Position ◽  
Data Set ◽  
Living Fossil ◽  
Latimeria Chalumnae ◽  
Relationship Of

The complete nucleotide sequence of the 16,407-bp mitochondrial genome of the coelacanth (Latimeria chalumnae) was determined. The coelacanth mitochondrial genome order is identical to the consensus vertebrate gene order which is also found in all ray-finned fishes, the lungfish, and most tetrapods. Base composition and codon usage also conform to typical vertebrate patterns. The entire mitochondrial genome was PCR-amplified with 24 sets of primers that are expected to amplify homologous regions in other related vertebrate species. Analyses of the control region of the coelacanth mitochondrial genome revealed the existence of four 22-bp tandem repeats close to its 3′ end. The phylogenetic analyses of a large data set combining genes coding for rRNAs, tRNA, and proteins (16,140 characters) confirmed the phylogenetic position of the coelacanth as a lobe-finned fish; it is more closely related to tetrapods than to ray-finned fishes. However, different phylogenetic methods applied to this largest available molecular data set were unable to resolve unambiguously the relationship of the coelacanth to the two other groups of extant lobe-finned fishes, the lungfishes and the tetrapods. Maximum parsimony favored a lungfish/coelacanth or a lungfish/tetrapod sistergroup relationship depending on which transversion:transition weighting is assumed. Neighbor-joining and maximum likelihood supported a lungfish/tetrapod sistergroup relationship.

scholarly journals Loose Ends in the Cortinarius Phylogeny: Five New Myxotelamonoid Species Indicate a High Diversity of These Ectomycorrhizal Fungi with South American Nothofagaceae

Life ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 420
Author(s):  
María Eugenia Salgado Salomón ◽  
Carolina Barroetaveña ◽  
Tuula Niskanen ◽  
Kare Liimatainen ◽  
Matthew E. Smith ◽  
...  
Keyword(s):  
New Species ◽  
Current Knowledge ◽  
Phylogenetic Analyses ◽  
Molecular Data ◽  
Global Scale ◽  
South American ◽  
Edible Fungi ◽  
Rdna Its ◽  
Morphological And Molecular Data ◽  
High Diversity

This paper is a contribution to the current knowledge of taxonomy, ecology and distribution of South American Cortinarius (Pers.) Gray. Cortinarius is among the most widely distributed and species-rich basidiomycete genera occurring with South American Nothofagaceae and species are found in many distinct habitats, including shrublands and forests. Due to their ectomycorrhizal role, Cortinarius species are critical for nutrient cycling in forests, especially at higher latitudes. Some species have also been reported as edible fungi with high nutritional quality. Our aim is to unravel the taxonomy of selected Cortinarius belonging to phlegmacioid and myxotelamonioid species based on morphological and molecular data. After widely sampling Cortinarius specimens in Patagonian Nothofagaceae forests and comparing them to reference collections (including holotypes), we propose five new species of Cortinarius in this work. Phylogenetic analyses of concatenated rDNA ITS-LSU and RPB1 sequences failed to place these new species into known Cortinarius sections or lineages. These findings highlight our knowledge gaps regarding the fungal diversity of South American Nothofagaceae forests. Due to the high diversity of endemic Patagonian taxa, it is clear that the South American Cortinarius diversity needs to be discovered and described in order to understand the evolutionary history of Cortinarius on a global scale.

scholarly journals Disentangling relationships among eastern Mediterranean Cymbalaria including description of a novel species from the southern Peloponnese (Greece)

2021 ◽  
Vol 307 (2) ◽  
Author(s):  
Pau Carnicero ◽  
Núria Garcia-Jacas ◽  
Llorenç Sáez ◽  
Theophanis Constantinidis ◽  
Mercè Galbany-Casals
Keyword(s):  
Eastern Mediterranean ◽  
Phylogenetic Analyses ◽  
Taxonomic Revision ◽  
Distribution Patterns ◽  
Morphological Characters ◽  
Molecular Data ◽  
Morphological Data ◽  
Long Distance ◽  
Aegean Islands ◽  
Molecular Phylogenetic

AbstractThe eastern Mediterranean basin hosts a remarkably high plant diversity. Historical connections between currently isolated areas across the Aegean region and long-distance dispersal events have been invoked to explain current distribution patterns of species. According to most recent treatments, at least two Cymbalaria species occur in this area, Cymbalaria microcalyx and C. longipes. The former comprises several intraspecific taxa, treated at different ranks by different authors based on morphological data, evidencing the need of a taxonomic revision. Additionally, some populations of C. microcalyx show exclusive morphological characters that do not match any described taxon. Here, we aim to shed light on the systematics of eastern Mediterranean Cymbalaria and to propose a classification informed by various sources of evidence. We performed molecular phylogenetic analyses using ITS, 3’ETS, ndhF and rpl32-trnL sequences and estimated the ploidy level of some taxa performing relative genome size measures. Molecular data combined with morphology support the division of traditionally delimited C. microcalyx into C. acutiloba, C. microcalyx and C. minor, corresponding to well-delimited nrDNA lineages. Furthermore, we propose to combine C. microcalyx subsp. paradoxa at the species level. A group of specimens previously thought to belong to Cymbalaria microcalyx constitute a well-defined phylogenetic and morphological entity and are described here as a new species, Cymbalaria spetae. Cymbalaria longipes is non-monophyletic, but characterized by being glabrous and diploid, unlike other eastern species. The nrDNA data suggest at least two dispersals from the mainland to the Aegean Islands, potentially facilitated by marine regressions.

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