Phylogenetic relationships in the genus Closterium

Author(s):  
Nikita A. Martynenko ◽  
Evgeniy S. Gusev

Desmids are a large polyphyletic group of streptophyte algae, numbering about 4000 species. Traditionally, the taxonomy of desmids is based on morphological characters. However, the latest molecular genetic studies of the group conflict with the established taxonomy and indicate the polyphyletic position of some genera of this group of algae. The genus Closterium Nitzsch ex Ralfs, like the family Closteriaceae Bessey, forms a monophyletic clade on the general tree of Desmidiales, recovered on the data of both 18S rDNA and rbcL cpDNA. In our analysis of phylogenetic relationships within the genus Closterium, the existing strains formed 14 clades (species complexes). Within some complexes, some strains don’t differ phenotypically, but diverge on the phylogenetic tree, which indicates a hidden taxonomic diversity within the genus.

2002 ◽  
Vol 16 (1) ◽  
pp. 1 ◽  
Author(s):  
Mark E. Siddall

The phylogenetic relationships of the family Erpobdellidae, a group of non-sanguivorous leeches useful as bioindicators, were investigated with the combined use of morphological characters, mitochondrial cytochrome c oxidase subunit I, mitochondrial 12S rDNA and nuclear 18S rDNA. Analyses of separate data sets and the combined data provide strong support for the contention that generic distinctions in the family are not reflective of phylogeny. The resulting hypothesis indicates the number of pairs of labial eyes as the sole morphological predictor of phylogenetic relationship. The traditionally used degree of annular subdivision is the least consistent character. In the absence of readily definable morphological synapomorphies for the resulting clades, the genera Dina, Mooreobdella, Nephelopsis and Trocheta are formally synonymised under the genus Erpobdella, the type genus of the family.


2005 ◽  
Vol 26 (2) ◽  
pp. 139-147 ◽  
Author(s):  
Francisca do Val ◽  
Paulo Nuin

AbstractThe systematics and phylogenetic relationships of the family Leptodactylidae are controversial as is the intrafamilial phylogeny of the leptodactylids. Here we analyze the relationships of the leptodactylid subfamily Hylodinae. This subfamily has been considered to be monophyletic and composed of three genera, Hylodes, Crossodactylus and Megaelosia. In the present study 49 characters were used, based on different studies on Leptodactylidae phylogeny. Maximum parsimony methods with unweighted and successively weighted characters were used to estimate the phylogeny of the Hylodinae. Upon analysis, the data provided further evidence of the monophyletic status of the three genera, with Megaelosia being the basal genus and the other two genera being sister taxa. The analysis with successive weighting results in a more resolved topology of the species subgroups of the genus Hylodes and separates this genus from Crossodactylus and confirms that the hylodines are monophyletic.


Author(s):  
E. D. Kasyanov ◽  
G. E. Maso ◽  
A. O. Kibitov

Affective disorders (recurrent depressive disorder and bipolar affective disorder) are multifactorial and polygenic diseases, which suggests the involvement of multiple neurobiological mechanisms. The phenotype of affective disorders is a heterogeneous group of clinically similar psychopathological symptoms, which also makes it difficult to detect potential biomarkers and new therapeutic targets. To study families at high risk of developing affective disorders using both clinical and molecular genetic approaches can help to study the neurobiological basis of depressive conditions, as well as to identify endophenotypes of affective disorders. The most important criterion for an endophenotype is its heritability, which can be proved only within the framework of the family design of the study. Comprehensive clinical and molecular genetic studies based on family design have the best prospects.


2011 ◽  
Vol 279 (1731) ◽  
pp. 1093-1099 ◽  
Author(s):  
Maria Heikkilä ◽  
Lauri Kaila ◽  
Marko Mutanen ◽  
Carlos Peña ◽  
Niklas Wahlberg

Although the taxonomy of the ca 18 000 species of butterflies and skippers is well known, the family-level relationships are still debated. Here, we present, to our knowledge, the most comprehensive phylogenetic analysis of the superfamilies Papilionoidea, Hesperioidea and Hedyloidea to date based on morphological and molecular data. We reconstructed their phylogenetic relationships using parsimony and Bayesian approaches. We estimated times and rates of diversification along lineages in order to reconstruct their evolutionary history. Our results suggest that the butterflies, as traditionally understood, are paraphyletic, with Papilionidae being the sister-group to Hesperioidea, Hedyloidea and all other butterflies. Hence, the families in the current three superfamilies should be placed in a single superfamily Papilionoidea. In addition, we find that Hedylidae is sister to Hesperiidae, and this novel relationship is supported by two morphological characters. The families diverged in the Early Cretaceous but diversified after the Cretaceous–Palaeogene event. The diversification of butterflies is characterized by a slow speciation rate in the lineage leading to Baronia brevicornis , a period of stasis by the skippers after divergence and a burst of diversification in the lineages leading to Nymphalidae, Riodinidae and Lycaenidae.


2020 ◽  
Vol 96 (2) ◽  
pp. 455-498
Author(s):  
Kai Horst George

Uncovering the systematics of CopepodaHarpacticoida, the second-most abundant component of the meiobenthos after Nematoda, is of major importance for any further research dedicated especially to ecological and biogeographical approaches. Based on the evolution of the podogennontan first swimming leg, a new phylogenetic concept of the Ancorabolidae Sars and Cletodidae T. Scott sensu Por (Copepoda, Harpacticoida) is presented, using morphological characteristics. It confirms the polyphyletic status of the Ancorabolidae and its subfamily Ancorabolinae Sars and the paraphyletic status of the subfamily Laophontodinae Lang. Moreover, it clarifies the phylogenetic relationships of the so far assigned members of the family. An exhaustive phylogenetic analysis was undertaken using 150 morphological characters, resulting in the establishment of a now well-justified monophylum Ancorabolidae. In that context, the Ancorabolus-lineage sensu Conroy-Dalton and Huys is elevated to sub-family rank. Furthermore, the membership of Ancorabolina George in a rearranged monophylum Laophontodinae is confirmed. Conversely, the Ceratonotus-group sensu Conroy-Dalton is transferred from the hitherto Ancorabolinae to the Cletodidae. Within these, the Ceratonotus-group and its hypothesised sister-group Cletodes Brady are combined to form a monophyletic subfamily Cletodinae T. Scott, subfam. nov. Consequently, it was necessary to restructure the Ancorabolidae, Ancorabolinae and Laophontodinae and extend the Cletodidae to include the displacement and exclusion of certain taxa. Moreover, comparison of the Ancorabolidae, Cletodidae, Laophontoidea and other Podogennonta shows that the Ancorabolidae and Cletodidae form sister-groups in a monophylum Cletodoidea Bowman and Abele, which similarly has a sister-group-relationship with the Laophontoidea T. Scott. According to the present study, both taxa constitute a derived monophylum within the Podogennonta Lang.


2020 ◽  
Vol 51 (3) ◽  
pp. 296-346
Author(s):  
Magno S. Ramos ◽  
Celso O. Azevedo

Bethylinae are a morphologically well-defined subfamily of Bethylidae, with remarkable characters, such as strongly convex clypeal carina and bifid and angled tarsal claws. However, there is no consensus about the phylogenetic relationships among the genera within the family, regarding mainly Eupsenella and Lytopsenella. To resolve this problem, a phylogeny of the Bethylinae is inferred based on parsimony analyses separately of 43 and 44 morphological characters for males and females, respectively. We performed combined analyses of both sexes with 49 morphological characters, including genitalia. We present a phylogenetic analysis, including a total 118 species of Bethylinae. Male and female characters were included in these analyses. We discuss wing morphology and deformability of forewings for the first time. In summary, the basal polytomy was solved for the first time. Seven of the eight genera were recovered as monophyletic groups. The unique exception is Goniozus, which was retrieved as paraphyletic in all topologies.


Zootaxa ◽  
2009 ◽  
Vol 2022 (1) ◽  
pp. 1-14 ◽  
Author(s):  
RAFAEL LEMAITRE ◽  
PATSY A. MCLAUGHLIN ◽  
ULF SORHANNUS

Phylogenetic relationships within the “symmetrical” hermit crab family Pylochelidae were analyzed for 41 of the 45 species and subspecies currently considered valid. In the analyses, 78 morphological characters comprised the data matrix and the outgroup consisted of Thalassina anomala, a member of the Thalassinidae, and Munida quadrispina, a member of the Galatheidae. A poorly resolved strict consensus tree was obtained from a heuristic parsimony analysis of unweighted and unordered characters, which showed the family Pylochelidae and the subfamilies Pylochelinae and Pomatochelinae to be monophyletic taxa – the latter two groups had the highest Bremer support values. Additionally, while the subgenus Pylocheles (Pylocheles) was strongly supported, the subgenera Xylocheles, and Bathycheles were not. More fully resolved trees were obtained when using implied weighting, which recognized the monotypic subfamilies Parapylochelinae, Cancellochelinae and Mixtopagurinae. The subfamily Trizochelinae was found to have four distinct clades and several ambiguously placed taxa.


1997 ◽  
Vol 75 (6) ◽  
pp. 963-970 ◽  
Author(s):  
André-Denis G. Wright ◽  
Denis H. Lynn

Phylogenetic relationships within the largest family of entodiniomorphid rumen ciliates, the Ophryoscolecidae, were inferred from comparisons of small-subunit ribosomal RNA gene sequences. These included three new sequences from Diplodinium dentatum (1638 base pairs (bp)), Eudiplodinium maggii (1637 bp), and Ophryoscolex purkynjei (1636 bp). Using morphological characters, Lubinsky constructed a cladogram of the Ophryoscolecidae, and on the basis of his analysis, he divided the family into three subfamilies (Entodiniinae, Diplodiniinae, Ophryoscolecinae) to reflect his "natural" groupings (G. Lubinsky. 1957. Can. J. Zool. 35: 141 – 159). Our cladistic analysis, based on the limited morphological and ultrastructural data available, indicates that there are no synapomorphies supporting the Diplodiniinae sensu Lubinsky. However, based upon the six 18S sequences for the Ophryoscolecidae, the rumen ciliates are monophyletic and fall into three distinct groups corresponding to Lubinsky's subfamilial division of the family. Our molecular analysis shows Entodinium to be the earliest branching rumen ciliate (subfamily Entodiniinae) and Eudiplodinium, not Diplodiium, branching first among the diplodiniines.


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