Diversity of the Pterasteridae (Asteroidea) in the Southern Ocean: a molecular and morphological approach

Author(s):  
Quentin Jossart ◽  
Marc Kochzius ◽  
Bruno Danis ◽  
Thomas Saucède ◽  
Camille V E Moreau

Abstract An integrative approach is crucial in discrimination of species, especially for taxa that are difficult to identify based on morphological characters. In this study, we combine genetics and morphology to assess the diversity of Pterasteridae, a sea star family diversified in deep-sea and polar environments. Because of their derived anatomy and the frequent loss of characters during preservation, Pterasteridae are a suitable case for an integrative study. The molecular identification of 191 specimens (mostly from the Southern Ocean) suggests 26–33 species in three genera (Diplopteraster, Hymenaster and Pteraster), which match the morphological identification in 54–62% of cases. The mismatches are either different molecular units that are morphologically indistinguishable (e.g. Pteraster stellifer units 2 and 4) or, conversely, nominal species that are genetically identical (e.g. Hymenaster coccinatus/densus/praecoquis). Several species are shared between the Northern and Southern Hemispheres (e.g. Pteraster jordani/affinis). In conclusion, the taxonomic status of some groups is confirmed, but for others we find the need to re-evaluate the taxonomy at both genus and species levels. This work significantly increases the DNA barcode library of the Southern Ocean species and merges taxonomic information into an identification key that could become a baseline for future studies (pterasteridae-so.identificationkey.org).

2015 ◽  
Vol 2015 ◽  
pp. 1-21 ◽  
Author(s):  
Julian J. Dodson ◽  
Frédéric Lecomte

Species of the genus Hemibagrus are large river catfishes found throughout South-east Asia. The complexity of the region’s biogeographical history and the lack of well-defined morphological characters render the taxonomy and phylogenetic reconstruction of Hemibagrus problematical. Early molecular studies of the H. nemurus species group revealed extensive genetic subdivisions, the taxonomic status of which remained unclear. A recent, morphologically-based, revision of the genus provides an opportunity to clarify the taxonomic status of these lineages. We employ a DNA barcode derived from the mitochondrial cytochrome b gene to expand our genetic analyses of the genus and to test the congruence of morphologically and genetically based taxonomies. Secondly, we evaluate phylogenetic relationships among taxa. Thirdly, we describe the phylogeography of Hemibagrus in South-east Asia. The species groups and nominal species proposed in the morphology-based revision generally reflect a hierarchy of monophyletic groups based on phenetic and maximum likelihood reconstructions of mtDNA phylogenies. The most notable exception involves the definition of a morphologically cryptic group from North Borneo. H. nemurus from West Java appears to be a regional population of H. capitulum. The phylogeography of the genus has been principally influenced by the formation of North Borneo and the emergence of the Sunda Islands.


Zootaxa ◽  
2021 ◽  
Vol 5068 (2) ◽  
pp. 211-239
Author(s):  
CLAUDIA LANSAC ◽  
RODRIGO AGUAYO ◽  
IGNACIO DE LA RIVA

The genus Gastrotheca (Anura: Hemiphractidae) is a group of marsupial frogs particularly diverse in Andean regions. Several taxonomic studies of this genus have been conducted in the humid cloud forests—or Yungas—of the Andean eastern slopes of central Bolivia (departments of Cochabamba and Santa Cruz). Yet, the distinction among three species that occur sympatrically in these forests, G. lauzuricae (proposed as a junior synonym of G. coeruleomaculatus in 2015), G. piperata, and G. splendens, remains unclear since the morphological characters that purportedly support their differentiation are variable and partly shared among them. We have carried out external morphological studies, including multivariate morphometric analyses, to assess how they support the taxonomic status of these three species. We also evaluated characters of the cranial osteology of a sample of six individuals using micro CT-scanning. Principal component and linear discriminant analyses resulted in a great overlap among the putative species. Cranial osteological comparisons did not reveal highly significant differences among them, but suggested that different degrees of hyperossification could be related to the developmental state of individuals. Our results indicate that most morphological and osteological reported differences between the three species likely represent intraspecific variation. Thus, we propose that the three nominal species belong to a single biological entity, for which the name Gastrotheca splendens (Schmidt, 1857) has priority. We also restrict the name Gastrotheca coeruleomaculatus (Werner, 1899) to externally similar congeneric populations from the Yungas forests of department of La Paz, but highlighting the need of a detailed evaluation of their taxonomic identity.  


Author(s):  
Udon Pongkawong ◽  
◽  
Jatupol Kampuansai ◽  
Rossarin Pollawatn ◽  
Arunothai Jampeetong ◽  
...  

Abstract “Dok Hin” is the Thai local name for Selaginella species that form rosettes. They commonly distributes in Siberia, Manchuria, southern China, Japan, the Philippines and Thailand. Morphology of Dok Hin is very resemble leading to misidentification. So, exactly number of species of Dok Hin in Thailand and their differences in morphological characteristics is not well understood. Thus, revision of morphological characters and phylogenetic confirmation of the taxonomic identification are needed. This study aims to examine morphological charateristics and phylogenetic patterns in eight populations of the Dok Hin in Northern Thailand. Morphology of Dok Hin from each populations was quantitatively examined using 15 vegetative and 6 reproductive characters meanwhile phylogenetic analyses was explored by DNA barcode ITS2. The results of the phylogenetic analysis revealed the existence of two species of Dok Hin, S. tamariscina and S. pulvinata. Selaginella tamariscina can be distinguished from S. pulvinata by its presence of a pseudotrunk above ground and ridges of dorsal leaves. On the other hand, the results of phylogenetic analysis indicated the differences among populations of S. pulvinata as well. Chiang Mai populations of S. pulvinata was characterized by peculiar set of characters long leaves and leaf apices look like caudate, while the rest of their populations have shorter leaves and leaf apices look like aristate. It indicates that S. pulvinata has genetic and phenotypic divergence among populations. However, additional studies of Dok Hin populations in other parts of Thailand and studies on different genetic markers are necessary to confirm the taxonomic status of S. pulvinata. Keywords: Dok Hin, Morphometric, Phylogeny, Pseudotrunk, Resurrection plant


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Abner Carvalho-Batista ◽  
Mariana Terossi ◽  
Fernando J. Zara ◽  
Fernando L. Mantelatto ◽  
Rogerio C. Costa

Abstract After being stable for nearly a century, the taxonomic history of the genus Xiphopenaeus has been marked by many changes in the last three decades. The taxonomic status of the Atlantic species has a low resolution, and many species are still undefined and grouped as cryptic species. Here we employed an integrative approach to define the species of Xiphopenaeus and the morphological characters needed to differentiate them. We combined the analyses of two molecular markers (COI and 16 S rDNA), scanning electron microscopy and light microscopy. Based on specimens from 17 localities from the Atlantic and Pacific oceans, we detected five divergent genetic groups, three in the Atlantic (A1, A2, A3) and two in the Pacific (P1, P2). Male secondary sexual characters were able to differentiate four out of the five genetic groups. Group A1 corresponds to X. kroyeri, and A2 and A3 correspond to new species. We redescribed the genus and two new species are described and illustrated: Xiphopenaeus dincao nov. sp. (A2) and Xiphopenaeus baueri nov. sp. (A3). Since the holotype of X. riveti was missing and the specimen analysed from group P2 was a female, the status of the species of Xiphopenaeus from the Pacific remains unresolved.


Zootaxa ◽  
2020 ◽  
Vol 4816 (1) ◽  
pp. 1-48 ◽  
Author(s):  
ISABEL C. MOLINA-ACEVEDO ◽  
IZWANDY IDRIS

Marphysa sanguinea Montagu, 1813, the type species of genus Marphysa, was described with few characteristics and subsequently reported in tropical and temperate waters as a cosmopolitan species. Recent comparative studies have shown that M. sanguinea has a limited distribution to the Northeast Atlantic. As a result, species from the tropical and subtropical zones are now being redescribed as new species. However, this issue is not completely resolved because of the taxonomic status of seven nominal species, considered as junior synonymies of M. sanguinea. Herein, we examined the type and additional materials from five species in synonymy M. sanguinea and performed a compared analysis with the neotype of M. sanguinea. Additionally, we reviewed specimens from two localities in the mid-Pacific Ocean and the Adriatic Sea, where M. sanguinea was previously reported. As a result of this study, three species were reinstated (M. californica Moore, 1909, M. leidii de Quatrefages, 1866, and M. parishii Baird, 1869) and two subspecies, are now raised to species level (M. americana n. status and M. brevibranchiata n. status). In addition, two new species from Hawaii and Croatia are described: M. baileybrockae n. sp. and M. birgeri n. sp., respectively. Morphological comparisons with most species currently assigned to the M. sanguinea complex are presented. This work provides more support for rejecting the hypothesis that M. sanguinea is a cosmopolitan species and we encourage the use of novel and traditional morphological characters to differentiate species within the complex. 


2018 ◽  
Vol 109 (3) ◽  
pp. 342-355 ◽  
Author(s):  
A. Petrović ◽  
M. Mitrović ◽  
M.E. Ghaliow ◽  
A. Ivanović ◽  
N.G. Kavallieratos ◽  
...  

AbstractSpecies that belong to the Aphidius eadyi group have been used as biocontrol agents against Acyrthosiphon pisum worldwide. However, despite their extensive use, there are still gaps in our knowledge about their taxonomy and distribution. In this study, we employed an integrative taxonomic approach by combining genetic analyses (mtDNA COI barcoding) with standard morphological analyses and geometric morphometrics of forewing shape. We identified three species within the A. eadyi species group, viz., A. smithi, A. eadyi and A. banksae. Genetic separation of all three species was confirmed, with mean genetic distances between species ranging from 5 to 7.4%. The following morphological characters were determined as the most important for separating species of the A. eadyi group: number and shape of costulae on the anterolateral part of the petiole, shape of the central areola on the propodeum, and shape and venation of the forewings. The differences in wing shape of all three species were statistically significant, but with some overlapping. We identified A. banksae as a widely distributed pea aphid parasitoid, whose known range covers most of the western Palaearctic (from the UK to Israel). Aphidius banksae is diagnosed and redescribed.


PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e10073
Author(s):  
Priscila S. Carvalho ◽  
Hussam Zaher ◽  
Nelson J. da Silva Jr ◽  
Diego J. Santana

Background Studies with integrative approaches (based on different lines of evidence) are fundamental for understanding the diversity of organisms. Different data sources can improve the understanding of the taxonomy and evolution of snakes. We used this integrative approach to verify the taxonomic status of Hydrodynastes gigas (Duméril, Bibron & Duméril, 1854), given its wide distribution throughout South America, including the validity of the recently described Hydrodynastes melanogigas Franco, Fernandes & Bentim, 2007. Methods We performed a phylogenetic analysis of Bayesian Inference with mtDNA 16S and Cytb, and nuDNA Cmos and NT3 concatenated (1,902 bp). In addition, we performed traditional morphometric analyses, meristic, hemipenis morphology and coloration pattern of H. gigas and H. melanogigas. Results According to molecular and morphological characters, H. gigas is widely distributed throughout South America. We found no evidence to support that H. gigas and H. melanogigas species are distinct lineages, therefore, H. melanogigas is a junior synonym of H. gigas. Thus, the melanic pattern of H. melanogigas is the result of a polymorphism of H. gigas. Melanic populations of H. gigas can be found in the Tocantins-Araguaia basin.


Zootaxa ◽  
2018 ◽  
Vol 4422 (4) ◽  
pp. 537
Author(s):  
EDUARDO P. BARBOSA ◽  
RICARDO R. SIEWERT ◽  
OLAF H. H. MIELKE ◽  
GERARDO LAMAS ◽  
KEITH R. WILLMOTT ◽  
...  

Euptychia saltuensis Hayward, 1962, new synonym, currently regarded as a nomen dubium and possibly a junior subjective synonym of Yphthimoides manasses (C. Felder & R. Felder, 1867), is here treated as a junior subjective synonym of Yphthimoides patricia (Hayward, 1957), based on morphological characters of the male genitalia and the DNA barcode. The taxonomic status of Y. patricia is re-examined, and a detailed redescription of the adult morphology, including the male genitalia, is presented. Information on the distribution, habitat and immature stages of Y. patricia is also provided. Yphthimoides patricia is clearly a distinct species from Y. manasses based on the analysis of DNA barcode sequences and the morphology of the male genitalia.  


1997 ◽  
Vol 24 (1) ◽  
pp. 19-36 ◽  
Author(s):  
DALE R. CALDER ◽  
LESTER D. STEPHENS

Samuel Fessenden Clarke was the leading specialist on hydroids (phylum Cnidaria) in North America over the last quarter of the nineteenth century. During that period he published taxonomic papers on hydroids from both the Atlantic and Pacific coasts of the continent, from the Gulf of Mexico, and from the eastern Pacific off Central and South America. He also authored a section on hydrozoan biology for “The Riverside Natural History” series. Most of his papers on hydroids were published while he was in his twenties. Clarke described as new 61 nominal species, three nominal genera, and one nominal family, as well as two “varieties” of hydroids. A list of these, and their current taxonomic status, appears in the present work. Clarke consistently provided sound descriptions and locality data for all supposed new species, and drew accurate illustrations of most of them. His research on Hydrozoa, beyond alphataxonomy, was directed towards faunal distributions and the use of hydroid assemblages as biogeographic indicators. In addition to investigations on hydroids, Clarke carried out research on the developmental biology of amphibians and reptiles. His doctoral dissertation at Johns Hopkins University was based on the embryology of the “Spotted Salamander” (=Yellow-spotted Salamander), and he published a major paper on the habits and embryology of the American Alligator. Most of Clarke's career was devoted to academic duties at Williams College, Massachusetts, where he was recognized as a dedicated and inspiring teacher. He served the American Society of Naturalists in various capacities, including a term as its president, was an influential trustee of the Marine Biological Laboratory, Woods Hole, and promoted the study of science in American schools.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Edoardo Massa ◽  
Roberto Guidetti ◽  
Michele Cesari ◽  
Lorena Rebecchi ◽  
K. Ingemar Jönsson

AbstractKristianstads Vattenrike Biosphere Reserve [KVBR] is a UNESCO designated area of Sweden possessing high biological value. Although several studies on tardigrades inhabiting Sweden have been performed, the KVBR area has been neglected. The current study investigates the tardigrade fauna of five areas of the biosphere reserve and includes 34 samples of different substrates analysed quantitatively and qualitatively. In total, 33 species of tardigrades were found in the samples, including 22 new records for the Skåne region, 15 new records for Sweden, and four species new to science. Mesobiotus emiliae sp. nov., Xerobiotus gretae sp. nov., Itaquascon magnussoni sp. nov., and Thulinius gustavi sp. nov. were described with an integrative approach (when possible) using morphological characters (light, electron scanning, and confocal laser scanning microscopies) and molecular markers (ITS2, 18S, 28S, cox1). A new protocol to increase morphological data was developed recovering mounted specimens within old slides for SEM analysis. Emended diagnoses for the genus Itaquascon and the transfer of Platicrista itaquasconoide to the genus Meplitumen are proposed. This study enriches the knowledge of the tardigrade biodiversity both within the KVBR and in Sweden and contributes to the rapidly increasing number of tardigrade species reported worldwide. The 33 species identified in the KVBR area represents 28% of all water bear species found in Sweden so far. The restricted study areas and limited number of samples collected suggests that the KVBR is very rich of tardigrades.


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