01890nas a2200157   4500008004100000245015400041210007100195260000900266300001100275490000600286520131800292100002901610700002201639700002501661856004601686       2010                        eng d00aMolecules clarify a cnidarian life cycle–the "hydrozoan" Microhydrula limopsicola is an early life stage of the staurozoan Haliclystus antarcticus.0 aMolecules clarify a cnidarian life cycle–the hydrozoan Microhydr  c2010  ae101820 v53 aBACKGROUND: Life cycles of medusozoan cnidarians vary widely, and have been difficult to document, especially in the most recently proposed class Staurozoa. However, molecular data can be a useful tool to elucidate medusozoan life cycles by tying together different life history stages. METHODOLOGY/PRINCIPAL FINDINGS: Genetic data from fast-evolving molecular markers (mitochondrial 16S, nuclear ITS1, and nuclear ITS2) show that animals that were presumed to be a hydrozoan, Microhydrula limopsicola (Limnomedusae, Microhydrulidae), are actually an early stage of the life cycle of the staurozoan Haliclystus antarcticus (Stauromedusae, Lucernariidae). CONCLUSIONS/SIGNIFICANCE: Similarity between the haplotypes of three markers of Microhydrula limopsicola and Haliclystus antarcticus settles the identity of these taxa, expanding our understanding of the staurozoan life cycle, which was thought to be more straightforward and simple. A synthetic discussion of prior observations makes sense of the morphological, histological and behavioral similarities/congruence between Microhydrula and Haliclystus. The consequences are likely to be replicated in other medusozoan groups. For instance we hypothesize that other species of Microhydrulidae are likely to represent life stages of other species of Staurozoa.1 aMiranda, Luc{\'ılia, S.1 aCollins, Allen, G1 aMarques, Antonio, C.  uhttps://staurozoa.myspecies.info/node/45200662nas a2200169   4500008004100000022005800041245015900099210006900258260001200327300001000339490000900349100002000358700002500378700002100403700002200424856004600446       2010                        eng d  a1175-5326 (print edition); 1175-5334 (online edition)00aHaliclystus californiensis, a “new” species of stauromedusa (Cnidaria: Staurozoa) from the northeast Pacific, with a key to the species of Haliclystus0 aHaliclystus californiensis a new species of stauromedusa Cnidari  c06/2010  a49-590 v25181 aKahn, Amanda, S1 aMatsumoto, George, I1 aHirano, Yayoi, M1 aCollins, Allen, G  uhttps://staurozoa.myspecies.info/node/45302922nas a2200193   4500008004100000245016400041210006900205260001300274300001100287490000700298520224400305100002202549700002102571700002502592700002202617700002002639700002302659856004602682       2006                        eng d00aMedusozoan phylogeny and character evolution clarified by new large and small subunit rDNA data and an assessment of the utility of phylogenetic mixture models0 aMedusozoan phylogeny and character evolution clarified by new la  c2006 Feb  a97-1150 v553 aA newly compiled data set of nearly complete sequences of the large subunit of the nuclear ribosome (LSU or 28S) sampled from 31 diverse medusozoans greatly clarifies the phylogenetic history of Cnidaria. These data have substantial power to discern among many of the competing hypotheses of relationship derived from prior work. Moreover, LSU data provide strong support at key nodes that were equivocal based on other molecular markers. Combining LSU sequences with those of the small subunit of the nuclear ribosome (SSU or 18S), we present a detailed working hypothesis of medusozoan relationships and discuss character evolution within this diverse clade. Stauromedusae, comprising the benthic, so-called stalked jellyfish, appears to be the sister group of all other medusozoans, implying that the free-swimming medusa stage, the motor nerve net, and statocysts of ecto-endodermal origin are features derived within Medusozoa. Cubozoans, which have had uncertain phylogenetic affinities since the elucidation of their life cycles, form a clade-named Acraspeda-with the scyphozoan groups Coronatae, Rhizostomeae, and Semaeostomeae. The polyps of both cubozoans and hydrozoans appear to be secondarily simplified. Hydrozoa is comprised by two well-supported clades, Trachylina and Hydroidolina. The position of Limnomedusae within Trachylina indicates that the ancestral hydrozoan had a biphasic life cycle and that the medusa was formed via an entocodon. Recently hypothesized homologies between the entocodon and bilaterian mesoderm are therefore suspect. Laingiomedusae, which has often been viewed as a close ally of the trachyline group Narcomedusae, is instead shown to be unambiguously a member of Hydroidolina. The important model organisms of the Hydra species complex are part of a clade, Aplanulata, with other hydrozoans possessing direct development not involving a ciliated planula stage. Finally, applying phylogenetic mixture models to our data proved to be of little additional value over a more traditional phylogenetic approach involving explicit hypothesis testing and bootstrap analyses under multiple optimality criteria. [18S; 28S; Cubozoa; Hydrozoa; medusa; molecular systematics; polyp; Scyphozoa; Staurozoa.].1 aCollins, Allen, G1 aSchuchert, Peter1 aMarques, Antonio, C.1 aJankowski, Thomas1 aMedina, Mónica1 aSchierwater, Bernd  uhttps://staurozoa.myspecies.info/node/46301723nas a2200145   4500008004100000245020700041210006900248260001300317300001100330490000800341520114000349100002201489700002001511856004601531       2005                        eng d00aA new deepwater species of Stauromedusae, Lucernaria janetae (Cnidaria, Staurozoa, Lucernariidae), and a preliminary investigation of stauromedusan phylogeny based on nuclear and mitochondrial rDNA data0 anew deepwater species of Stauromedusae Lucernaria janetae Cnidar  c2005 Jun  a221-300 v2083 aThe deepwater stauromedusan Lucernaria janetae n. sp is described from adult and juvenile specimens collected from the East Pacific Rise. Lucernaria janetae is the first species in the genus recorded from the Pacific Ocean, and differs from its congeners in size and morphology. Mitochondrial (16S) and nuclear (SSU) ribosomal gene sequences from L. janetae were analyzed with those of representative stauromedusan taxa to evaluate stauromedusan monophyly. Both genes recovered a strongly monophyletic Stauromedusae that is the sister group to all other medusozoans. Support of these hypotheses is robust to method of phylogenetic reconstruction and to outgroup selection, buttressing the argument that Stauromedusae should be recognized as the class Staurozoa. The molecular markers used here favor the same topology of relationships among our samples and clearly distinguished between two species, Haliclystus sanjuanensis and H. octoradiatus, that have been considered synonymous by many workers. A stable systematic framework for Stauromedusae appears achievable through comprehensive study of both morphological and sequence data.1 aCollins, Allen, G1 aDaly, Marymegan  uhttps://staurozoa.myspecies.info/node/465