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PubMed2004

Phylogenetic relationships of the African bush-shrikes and helmet-shrikes (Passeriformes: Malaconotidae).

The African bush-shrikes and helmet-shrikes (Malaconotidae sensu [A Complete Checklist of the Birds of the World, third ed., Helm Editions, London, 2003]) include 10 genera and 52 species of predatory passerine birds for which monophyly, sister-group, and inter-generic relationships are disputed. To resolve their relationships, we analyzed 2313 bp of sequence data obtained from two nuclear introns (myoglobin intron-2, beta-fibrinogen intron-5) and a mitochondrial protein-coding gene (ND2) using parsimony, maximum likelihood, and Bayesian inference. A strongly supported clade that included representatives of the Malaconotidae, Platysteiridae, and Vangidae was found in all analyses. Three main groups emerged within this clade but relationships between these three groups were always poorly supported. The first group included the helmet-shrikes (Prionops), flycatcher-shrikes (Bias and Megabyas), and vangas (Cyanolanius and Pseudobias), currently placed in the families Malaconotidae, Platysteiridae, and Vangidae, respectively. The second group consisted of four Platysteiridae genera (Lanioturdus, Batis, Platysteira, and Dyaphorophyia), with the remaining Malaconotidae genera ('core malaconotids') forming the last group. Two main clades emerged within the 'core malaconotids,' with the position of the genus Nilaus being variable. The first clade included Malaconotus, Dryoscopus, Bocagia, and Tchagra and the second Chlorophoneus, Laniarius, Rhodophoneus, and Telophorus. Monophyly of the genus Chlorophoneus was never recovered, a result that is consistent with morphological data.

Animals↗
PubMed2005

Molecular phylogenetics and evolutionary history of the neotropical Satyrine Subtribe Euptychiina (Nymphalidae: Satyrinae).

The Euptychiina is one of the more diverse lineages of satyrine butterflies, represented by over 300 species. The first phylogenetic analyses of the subtribe is presented based on 2506 aligned nucleotide sequences obtained from 69 individuals spanning 28 ingroup genera and nine outgroup genera. Two genes were used, the mitochondrial gene cytochrome oxidase 1 (1268 bp) and the nuclear gene elongation factor-1alpha (1238 bp). The subtribe is never recovered as monophyletic in analyses using parsimony, maximum likelihood, or Bayesian inference. Several euptychiine genera are placed basal to the ingroup, but support is found only for Euptychia and Oressinoma. Three main lineages within the ingroup were clearly defined and many taxonomic groupings within the clades strongly supported. The majority of genera tested were paraphyletic or polyphyletic. Based on results presented here and novel host use, a close relationship of Euptychia to the Indo-Australian tribe Ragadiini is hypothesized. Origins of the group remain unclear, but the basal position of most of the Nearctic genera is discussed.

Animals↗
PubMed2005

Resolving tylenchid evolutionary relationships through multiple gene analysis derived from EST data.

Sequence-based phylogenetic analyses typically are based on a small number of character sets and report gene trees which may not reflect the true species tree. We employed an EST mining strategy to suppress such incongruencies, and recovered the most robust phylogeny for five species of plant-parasitic nematode (Meloidogyne arenaria, M. chitwoodi, M. hapla, M. incognita, and M. javanica), three closely related tylenchid taxa (Heterodera glycines, Globodera pallida, and G. rostochiensis) and a distant taxon, Caenorhabditis elegans. Our multiple-gene approach is based on sampling more than 80,000 publicly available tylenchid EST sequences to identify phylum-wide orthologues. Bayesian inference, minimum evolution, maximum likelihood and protein distance methods were employed for phylogenetic reconstruction and hypothesis tests were constructed to elucidate differential selective pressures across the phylogeny for each gene. Our results place M. incognita and M. javanica as sister taxa, with M. arenaria as the next closely related nematode. Significant differences in selective pressure were revealed for some genes under some hypotheses, though all but one gene are exclusively under purifying selection, indicating conservation across the orthologous groups. This EST-based multi-gene analysis is a first step towards accomplishing genome-wide coverage for tylenchid evolutionary analyses.

Animals↗
PubMed2005

Incongruence between primary sequence data and the distribution of a mitochondrial atp1 group II intron among ferns and horsetails.

Using DNA sequence data from multiple genes (often from more than one genome compartment) to reconstruct phylogenetic relationships has become routine. Augmenting this approach with genomic structural characters (e.g., intron gain and loss, changes in gene order) as these data become available from comparative studies already has provided critical insight into some long-standing questions about the evolution of land plants. Here we report on the presence of a group II intron located in the mitochondrial atp1 gene of leptosporangiate and marattioid ferns. Primary sequence data for the atp1 gene are newly reported for 27 taxa, and results are presented from maximum likelihood-based phylogenetic analyses using Bayesian inference for 34 land plants in three data sets: (1) single-gene mitochondrial atp1 (exon+intron sequences); (2) five combined genes (mitochondrial atp1 [exon only]; plastid rbcL, atpB, rps4; nuclear SSU rDNA); and (3) same five combined genes plus morphology. All our phylogenetic analyses corroborate results from previous fern studies that used plastid and nuclear sequence data: the monophyly of euphyllophytes, as well as of monilophytes; whisk ferns (Psilotidae) sister to ophioglossoid ferns (Ophioglossidae); horsetails (Equisetopsida) sister to marattioid ferns (Marattiidae), which together are sister to the monophyletic leptosporangiate ferns. In contrast to the results from the primary sequence data, the genomic structural data (atp1 intron distribution pattern) would seem to suggest that leptosporangiate and marattioid ferns are monophyletic, and together they are the sister group to horsetails--a topology that is rarely reconstructed using primary sequence data.

Amino Acid Sequence↗
PubMed2005

Phylogenetic relationships of the lamprologine cichlid genus Lepidiolamprologus (Teleostei: Perciformes) based on mitochondrial and nuclear sequences, suggesting introgressive hybridization.

Using sequences of the mitochondrial NADH dehydrogenase subunit 2 gene (ND2, 1047bp) and a segment of the non-coding mitochondrial control region, as well as nuclear sequences including two introns from the S7 ribosomal protein and the loci TmoM25, TmoM27, and UME002, we explore the phylogenetic relationships of Lepidiolamprologus, one of seven lamprologine cichlid genera in Lake Tanganyika, East Africa. Analyses consisted of direct optimization using POY, including a parsimony sensitivity analysis, and maximum likelihood and Bayesian inference for comparison. With respect to Lepidiolamprologus, the results based on the mitochondrial dataset were robust to parameter variation in POY. Lepidiolamprologus cunningtoni was resolved in a large clade sister to ossified group lamprologines, among which the remaining Lepidiolamprologus were nested. In addition to L. attenuatus, L. elongatus, L. kendalli, and L. profundicola, Neolamprologus meeli, N. hecqui, N. boulengeri, N. variostigma, and two undescribed species were resolved in a two-pore Lepidiolamprologus clade sister to Lamprologus callipterus and two species of Altolamprologus. Lepidiolamprologus nkambae, in marked conflict with morphological and nuclear DNA evidence, nested outside of the two-pore Lepidiolamprologus clade, suggesting that the mtDNA signal has been convoluted by introgressive hybridization.

Animals↗
PubMed2005

Molecular phylogeny of the palm genus Chamaedorea, based on the low-copy nuclear genes PRK and RPB2.

Sequence data from the low-copy nuclear genes encoding phosphoribulokinase (PRK) and the second largest subunit of RNA polymerase II (RPB2) are used to generate the first phylogenetic analysis of Chamaedorea (Arecaceae: Arecoideae: Chamaedoreeae), the largest neotropical genus of palms. The prevailing current taxonomy of Chamaedorea recognizes approximately 100 species in eight subgenera, all delimited using floral characters, which provide a useful starting point to explore species-level systematics. Sequence data from 63 species, including representatives of all eight subgenera, were analyzed using maximum parsimony and Bayesian inference optimality criteria. Genus Chamaedorea is resolved as monophyletic with strong support in all separate and combined analyses. The less species-rich subgenera are convincingly monophyletic and can be diagnosed using morphological synapomorphies. In contrast, the two largest subgenera, Chamaedorea and Chamaedoropsis, which are supposedly distinguishable from each other by the degree of connation in the staminate petals, are both resolved as highly polyphyletic. Several well supported monophyletic groups resolved by these gene regions have never before been proposed within Chamaedorea and are challenging to delimit using morphological criteria. Although PRK proved more informative than RPB2, both regions have strong utility for interpreting species-level relationships among the palms, which are notoriously recalcitrant subjects for molecular phylogenetic studies. In addition, a paralog of the target copy of PRK identified during the analysis represents a potentially valuable source of phylogenetic information for future studies.

Arecaceae↗
PubMed2005

Testing morphologically based phylogenetic theories within the cartilaginous fishes with molecular data, with special reference to the catshark family (Chondrichthyes; Scyliorhinidae) and the interrelationships within them.

A molecular phylogenetic investigation was conducted to examine phylogenetic relationships between various members of the catsharks (Chondrichthyes; Carcharhiniformes; Scyliorhinidae), and is the largest chondrichthyan data set yet analysed, consisting of nearly 130,000 nucleotides. Three mitochondrial DNA genes were used to construct the phylogenies, cytochrome b, NADH-2, and NADH-4, with 41 sequences from 18 taxa being novel. These sequences were either used separately or combined into a single data set, and phylogenies were constructed using various methods, however, only the Bayesian inference tree derived from the cytochrome b data set was resolved sufficiently for phylogenetic inferences to be made. Interestingly, the family Scyliorhinidae was not supported by the results and was found to be paraphyletic. The Scyliorhininae and Pentanchinae were supported, whereas the Pentanchini clade was present, but not well supported. The Halaelurini hypothesis was supported with Holohalaelurus identified as the basal genus of that clade, and Haploblepharus edwardsii identified as the basal taxon for that genus. Elsewhere within the Chondrichthyes, the Carcharhiniformes and the Lamniformes were found to be monophyletic, and the Heterodontiformes was placed within the Squalimorphs. The placement of the skates and rays in these analyses support the Batoidea as being sister to the Elasmobranchii.

Animals↗
PubMed2006

Molecular evidence for the non-monophyletic status of Naidinae (Annelida, Clitellata, Tubificidae).

Naidinae (former Naididae) is a group of small aquatic clitellate annelids, common worldwide. In this study, we evaluated the phylogenetic status of Naidinae, and examined the phylogenetic relationships within the group. Sequence data from two mitochondrial genes (12S rDNA and 16S rDNA), and one nuclear gene (18S rDNA), were used. Sequences were obtained from 27 naidine species, 24 species from the other tubificid subfamilies, and five outgroup taxa. New sequences (in all 108) as well as GenBank data were used. The data were analysed by parsimony and Bayesian inference. The tree topologies emanating from the different analyses are congruent to a great extent. Naidinae is not found to be monophyletic. The naidine genus Pristina appears to be a derived group within a clade consisting of several genera (Ainudrilus, Epirodrilus, Monopylephorus, and Rhyacodrilus) from another tubificid subfamily, Rhyacodrilinae. These results demonstrate the need for a taxonomic revision: either Ainudrilus, Epirodrilus, Monopylephorus, and Rhyacodrilus should be included within Naidinae, or Pristina should be excluded from this subfamily. Monophyly of four out of six naidine genera represented by more than one species is supported: Chaetogaster, Dero, Paranais, and Pristina, respectively.

Animals↗
PubMed2006

A modern approach to rotiferan phylogeny: combining morphological and molecular data.

The phylogeny of selected members of the phylum Rotifera is examined based on analyses under parsimony direct optimization and Bayesian inference of phylogeny. Species of the higher metazoan lineages Acanthocephala, Micrognathozoa, Cycliophora, and potential outgroups are included to test rotiferan monophyly. The data include 74 morphological characters combined with DNA sequence data from four molecular loci, including the nuclear 18S rRNA, 28S rRNA, histone H3, and the mitochondrial cytochrome c oxidase subunit I. The combined molecular and total evidence analyses support the inclusion of Acanthocephala as a rotiferan ingroup, but do not support the inclusion of Micrognathozoa and Cycliophora. Within Rotifera, the monophyletic Monogononta is sister group to a clade consisting of Acanthocephala, Seisonidea, and Bdelloidea-for which we propose the name Hemirotifera. We also formally propose the inclusion of Acanthocephala within Rotifera, but maintaining the name Rotifera for the new expanded phylum. Within Monogononta, Gnesiotrocha and Ploima are also supported by the data. The relationships within Ploima remain unstable to parameter variation or to the method of phylogeny reconstruction and poorly supported, and the analyses showed that monophyly was questionable for the families Dicranophoridae, Notommatidae, and Brachionidae, and for the genus Proales. Otherwise, monophyly was generally supported for the represented ploimid families and genera.

Animals↗
PubMed2006

Molecular phylogeny of Banza (Orthoptera: Tettigoniidae), the endemic katydids of the Hawaiian Archipelago.

The extant endemic katydids (Orthoptera: Tettigoniidae) of the Hawaiian Archipelago include one to three species per high island and a single species on Nihoa, all currently placed in the genus Banza. These acoustic insects provide an excellent opportunity for investigating the evolution of reproductive isolation and speciation, but such studies require an understanding of phylogenetic relationships within the group. We use maximum parsimony, likelihood-based Bayesian inference, and maximum likelihood to infer phylogenetic relationships among these taxa, based on approximately 2kb of mitochondrial cytochrome oxidase I and cytochrome b. Our results strongly support two distinct high island clades: one clade ("Clade I") composed of species from Kauai, Oahu, Molokai, and Lanai and another clade ("Clade II") composed of species from Maui and Hawaii (Banza unica, from Oahu, may be basal to both these clades, but its placement is not well resolved). Within these clades, some inferred relationships are strongly supported, such as the sister status of B. kauaiensis (Kauai) and B. parvula (Oahu) within Clade I, but other relationships remain more ambiguous, such as the relative position of B. brunnea (Maui) within Clade II. Although a detailed reconstruction of the historical biogeography of the Hawaiian katydids is difficult, we use our genetic data combined with the known geological history of the Hawaiian Islands to set limits on plausible historical scenarios for diversification of this group. Beyond these historical biogeographic inferences, our results indicate possible cryptic speciation on both Oahu and Hawaii, as well as what may be unusually high average rates of nucleotide substitution. The present work sets the stage for future genetic and experimental investigations of this group.

Animals↗
PubMed2006

Phylogeography of Indonesian and Sino-Himalayan region bush warblers (Cettia, Aves).

We present a hypothesis for the phylogeny and phylogeography of a group of bush warblers in the genus Cettia, based on parts of the mitochondrial Cytochrome b gene and the nuclear myoglobin intron II (in all approximately 1.7 kb). Ancestral areas were reconstructed by dispersal-vicariance analysis and constrained Bayesian inference. The results suggest that the insular taxa in the Cettia vulcania group are most closely related to Cettia flavolivacea, and originated from a dispersal by an ancestral population in the Himalayas towards the south, to the Sunda region. From this population, a second dispersal along a different route colonized China and northern Vietnam. Hence, the Chinese taxon intricata and Vietnamese oblita, currently allocated to C. flavolivacea, are more closely related to the vulcania group than to the other taxa in the flavolivacea group, and we propose that they be treated as conspecific with C. vulcania, restricting C. flavolivacea to Myanmar and the Himalayas.

Animals↗
PubMed2006

Phylogenetic systematics of the colorful, cyanide-producing millipedes of Appalachia (Polydesmida, Xystodesmidae, Apheloriini) using a total evidence Bayesian approach.

Here, we provide an exemplar-approach phylogeny of the xystodesmid millipede tribe Apheloriini with a focus on genus-group relationships-particularly of the genus Brachoria. Exemplars for the phylogenetic analysis were chosen to represent the maximum breadth of morphological diversity within all nominal genera in the tribe Apheloriini, and to broadly sample the genus Brachoria. In addition, three closely related tribes were used (Rhysodesmini, Nannariini, and Pachydesmini). Morphological and DNA sequence data were scored for Bayesian inference of phylogeny. Phylogenetic analysis resulted in polyphyletic genera Brachoria and Sigmoria, a monophyletic Apheloriini, and a "southern clade" that contains most of the tribal species diversity. We used this phylogeny to track morphological character histories and reconstruct ancestral states using stochastic character mapping. Based on the findings from the character mapping study, the diagnostic feature of the genus Brachoria, the cingulum, evolved independently in two lineages. We compared our phylogeny against prior classifications using Bayes factor hypothesis-testing and found that our phylogenetic hypothesis is inconsistent with the previous hypotheses underlying the most recent classification. With our preferred total-evidence phylogeny as a framework for taxonomic modifications, we describe a new genus, Appalachioria; supply phylogenetic diagnoses of monophyletic taxa; and provide a phylogeny-based classification for the tribe Apheloriini.

Animals↗
PubMed2006

Molecular phylogeny of musk deer: a genomic view with mitochondrial 16S rRNA and cytochrome b gene.

The phylogenetic status of the infra order Pecora is controversial, even though it is supported by paleontological, morphological, and molecular evidence. We analyzed two mitochondrial genes (i.e., 16S rRNA and cytochrome b) to resolve the phylogenetic position of pecoran species, i.e., the Bovidae, Cervidae, and Moschidae endemic to the Indian subcontinent. We used phylogenetic analysis based on different algorithms, including neighbor joining, maximum parsimony, Bayesian inference, maximum likelihood, minimum evolution, median joining network, along with multidimensional scaling, and DNA word analysis. Our results established the basal position of Tragulidae and the monophyly of the infra order Pecora within the Suborder Ruminantia. Our results also demonstrated that Bovidae, Cervidae, and Moschidae are allied with the placement of musk deer as more closely related to bovids than to cervids. Molecular dating based on sequence analysis shows that the radiation of Pecora occurred during the early Oligocene and that the majority of the pecoran families radiated and dispersed rapidly during the Oligocene/Miocene transition.

Animals↗
PubMed2006

Re-examination and phylogeny of the genus Chondrostoma based on mitochondrial and nuclear data and the definition of 5 new genera.

Previous molecular phylogenetic studies of the genus Chondrostoma (Cyprinidae: Leuciscinae) were unable to resolve the relationship among its major species groups. In this paper we present a phylogeny for this genus, based on five mitochondrial genes and the nuclear gene beta-actin, comprising a total of 4068 bp. Bayesian inference using all gene fragments yielded a fully resolved phylogeny, compatible with topologies obtained from individual fragments using maximum parsimony and minimum evolution. Mapping of morphological characters critical to the rasping feeding mode of most Chondrostoma species indicates that they evolved several times, and questions the use of these characters in the traditional definition of the genus. Our findings led us to the definition of the following new genera: Achondrostoma, Iberochondrostoma, Pseudochondrostoma, Protochondrostoma and Parachondrostoma. Our data contradict the hypothesis of a rapid radiation during Lago Mare phase, suggested by previous studies.

Actins↗
PubMed2006

Phylogeny of the cave shrimp Troglocaris: Evidence of a young connection between Balkans and Caucasus.

The remarkably discontinuous distribution of the cave shrimp genus Troglocaris in South France, West Balkans, and West Caucasus has long been considered a biogeographic enigma. To solve it, its phylogeny was reconstructed by analyzing sequences from two mitochondrial (cytochrome oxidase I and 16S rRNA) and one nuclear gene (28S rRNA) using maximum likelihood, parsimony and Bayesian inference. The genus was found to be polyphyletic because the French taxon T. inermis had no direct common ancestry with other Troglocaris taxa but was sister to the epigean freshwater atyid Dugastella valentina. All other Troglocaris species constituted a well-supported monophylum, the second cave shrimp genus Spelaeocaris nested within. The monophylum had a well-defined structure: (1) a clade restricted to the Dinaric area of the Western Balkans containing the type species T. anophthalmus along with some unnamed species, and (2) a geographically mixed clade split between the Caucasian T. kutaissiana species complex on one, and T. hercegovinensis, S. pretneri, plus an unnamed taxon on the other side. It was surprising to find the dichotomy between the Caucasian and one of the West-Balkan lineages so low in the phylogenetic hierarchy of the genus. Taking into account molecular rates of other decapods, we tentatively dated this split at 6-11 Myr. This time is in agreement with the brackish and freshwater phase of the Paratethys thus allowing for a freshwater common ancestor of Caucasian and Dinaric cave shrimps. This would weaken the marine relicts hypothesis that has often been invoked to explain the distribution of freshwater cave species with close marine relatives.

Animals↗
PubMed2006

An improved molecular phylogeny of the Nematoda with special emphasis on marine taxa.

Phylogenetic reconstructions of relations within the phylum Nematoda are inherently difficult but have been advanced with the introduction of large-scale molecular-based techniques. However, the most recent revisions were heavily biased towards terrestrial and parasitic species and greater representation of clades containing marine species (e.g. Araeolaimida, Chromadorida, Desmodorida, Desmoscolecida, Enoplida, and Monhysterida) is needed for accurate coverage of known taxonomic diversity. We now add small subunit ribosomal DNA (SSU rDNA) sequences for 100 previously un-sequenced species of nematodes, including 46 marine taxa. SSU rDNA sequences for >200 taxa have been analysed based on Bayesian inference and LogDet-transformed distances. The resulting phylogenies provide support for (i) the re-classification of the Secernentea as the order Rhabditida that derived from a common ancestor of chromadorean orders Araeolaimida, Chromadorida, Desmodorida, Desmoscolecida, and Monhysterida and (ii) the position of Bunonema close to the Diplogasteroidea in the Rhabditina. Other, previously controversial relationships can now be resolved more clearly: (a) Alaimus, Campydora, and Trischistoma belong in the Enoplida, (b) Isolaimium is placed basally to a big clade containing the Axonolaimidae, Plectidae, and Rhabditida, (c) Xyzzors belongs in the Desmodoridae, (d) Comesomatidae and Cyartonema belongs in the Monhysterida, (e) Globodera belongs in the Hoplolaimidae and (f) Paratylenchus dianeae belongs in the Criconematoidea. However, the SSU gene did not provide significant support for the class Chromadoria or clear evidence for the relationship between the three classes, Enoplia, Dorylaimia, and Chromadoria. Furthermore, across the whole phylum, the phylogenetically informative characters of the SSU gene are not informative in a parsimony analysis, highlighting the short-comings of the parsimony method for large-scale phylogenetic modelling.

Animals↗
PubMed2006

Application of the secondary structure model of rRNA for phylogeny: D2-D3 expansion segments of the LSU gene of plant-parasitic nematodes from the family Hoplolaimidae Filipjev, 1934.

Knowledge of rRNA structure is increasingly important to assist phylogenetic analysis through reconstructing optimal alignment, utilizing molecule features as an additional source of data and refining appropriate models of evolution of the molecule. We describe a procedure of optimization for alignment and a new coding method for nucleotide sequence data using secondary structure models of the D2 and D3 expansion fragments of the LSU-rRNA gene reconstructed for fifteen nematode species of the agriculturally important and diverse family Hoplolaimidae, order Tylenchida. Using secondary structure information we converted the original sequence data into twenty-eight symbol codes and submitted the transformed data to maximum parsimony analysis. We also applied the original sequence data set for Bayesian inference. This used the doublet model with sixteen states of nucleotide doublets for the stem region and the standard model of DNA substitution with four nucleotide states for loops and bulges. By this approach, we demonstrate that using structural information for phylogenetic analyses led to trees with lower resolved relationships between clades and likely eliminated some artefactual support for misinterpreted relationships, such as paraphyly of Helicotylenchus or Rotylenchus. This study as well as future phylogenetic analyses is herein supported by the development of an on-line database, NEMrRNA, for rRNA molecules in a structural format for nematodes. We also have developed a new computer program, RNAstat, for calculation of nucleotide statistics designed and proposed for phylogenetic studies.

Animals↗
PubMed2006

Molecular phylogenetics in Hydra, a classical model in evolutionary developmental biology.

Among the earliest diverging animal phyla are the Cnidaria. Freshwater polyps of the genus Hydra (Cnidaria, Hydrozoa) have long been of general interest because different species of Hydra reveal fundamental principles that underlie development, differentiation, regeneration and also symbiosis. The phylogenetic relationships among the Hydra species most commonly used in current research are not resolved yet. Here we estimate the phylogenetic relations among eight scientifically important members of the genus Hydra with molecular data from two nuclear (18S rDNA, 28S rDNA) and two mitochondrial (16S rRNA, cytochrome oxidase subunit I (COI)) genes. The phylogenetic trees obtained by maximum parsimony (MP), maximum likelihood (ML) and Bayesian inference (BI) methods were generally compatible with present morphological classification patterns. However, the present analysis also bears on several long-standing questions about Hydra systematics and reveals some characteristics of the phylogenetic relationships of this genus that were unknown so far. It indicates that Hydra viridissima, the only species in Hydra, which contains symbiotic algae, might be considered as the sister group to all other species within this genus. Analyses of both nuclear and mitochondrial sequences support the view that Hydra oligactis and Hydra circumcincta are sisters to all other Hydra species. Unexpectedly, we also find that in contrast to its initial description, the strain used for making transgenic Hydra, Hydra vulgaris (strain AEP) is more closely related to Hydra carnea than to other species of Hydra.

Animals↗