Prosogynopora riseri, gen. et sp. nov., a phylogenetically problematic lithophoran proseriate (Platyhelminthes : Rhabditophora) with inverted genital pores from the New England coast

2014 ◽  
Vol 28 (3) ◽  
pp. 309 ◽  
Author(s):  
Christopher E. Laumer ◽  
Gonzalo Giribet ◽  
Marco Curini-Galletti

A new lithophoran proseriate flatworm, Prosogynopora riseri, gen. et sp. nov. (Platyhelminthes: Rhabditophora: Proseriata), is described from the New England coast (USA). The species shares characters with members of the families Calviriidae and Coelogynoporidae, e.g. the presence of paracnida, the short common female duct, a septum and diaphragm at the base of the pharynx. However, the inverted topology of the genital system, presenting an anterior female pore shortly behind the mouth and a male pore opening nearly on the caudal terminus, is unique within the Proseriata, and permits inclusion into neither family on morphological grounds. We investigated the phylogenetic position of the new species within the available diversity of proseriate 18S and 28S rRNA sequences. However, an exploration of diverse homology schemes, alignment conditions and optimality criteria proved the position of P. riseri, gen. et sp. nov. to be remarkably unstable, particularly with respect to the method of alignment, variously suggesting sister-group relationships with (or within) Coelogynoporidae, with Calviriidae, or with a clade composed of all other Lithophora. Despite its unique morphology and the absence of molecular phylogenetic evidence for its inclusion within any family as currently defined, we refrain from assigning a higher taxonomic rank to the new lineage, pending critical re-assessment of homology in several character systems and the availability of further taxon- and gene-rich enquiries into the phylogeny of Proseriata. Apingospermata, new taxon and Dolichogynoducta, new taxon are proposed as two rankless taxonomic names of Lithophora, corresponding to well-supported clades in our molecular phylogenetic hypothesis.

2021 ◽  
Author(s):  
Daria M. Kupaeva ◽  
Tatiana S. Lebedeva ◽  
Tatiana P. Ashurkova ◽  
Andrey A. Prudkovsky ◽  
Daniel Vanwalleghem ◽  
...  

The life-cycle and polyp morphology of Margelopsidae representatives are very different from all other Aplanulata cnidarians. Until recently, their evolutionary origin and phylogenetic position has been a subject of significant speculation. A recent molecular study based only on COI data unexpectedly placed Margelopsidae as a sister group to all Aplanulata, despite the Margelopsid morphology suggests affiliation with Tubulariidae or Corymorphidae. Here we used multigene analyses, including nuclear (18S rRNA and 28S rRNA) and mitochondrial (16S rRNA and COI) markers of the Margelopsidae hydroid Margelopsis haeckelii Hartlaub, 1897, to resolve its phylogenetic position with respect to other hydrozoans. Our data provides strong evidence that M. haeckelii is a member of the family Corymorphydae, making the family Margelopsidae invalid. Furthermore, we show that medusa previously known as M. harlaubii Browne, 1903 is sister to Plotocnide borealis, Wagner, 1885 and might be a member of Boreohydridae. The phylogenetic signal of polyp and medusа stages is discussed in light of concept of inconsistent evolution and molecular phylogenetic analysis.


Author(s):  
Nikolay G. ZVERKOV ◽  
Dmitry V. GRIGORIEV ◽  
Andrzej S. WOLNIEWICZ ◽  
Alexey G. KONSTANTINOV ◽  
Evgeny S. SOBOLEV

ABSTRACT The first ichthyosaurian specimens discovered from the Upper Triassic of the Russian Arctic (Kotelny Island, New Siberian Islands) are described herein. They include the remains of large- to small-bodied ichthyosaurians originating from six stratigraphic levels spanning the lower Carnian to middle Norian. The material is mostly represented by isolated vertebrae and ribs, which are not possible to accurately diagnose, but also includes specimens comprising associated vertebrae and a fragmentary skeleton that preserves cranial remains (parabasisphenoid, fragmentary quadrate, partial mandible and hyoids). Based on vertebral and rib morphology, we identify the specimens as representatives of the following taxonomic groups: large-bodied shastasaurids, medium-sized indeterminate ichthyosaurians with a single rib facet in the presacral centra, and small euichthyosaurians with double rib facets present throughout the presacral vertebrae that likely represent toretocnemids and/or basal parvipelvians. In addition, the cranial and mandibular remains preserved in one of the specimens, ZIN PH 5/250, were studied using micro-computed tomography. Its mandible is highly similar to that of toretocnemids, whereas the parabasisphenoid demonstrates a peculiar combination of both plesiomorphic and derived character states, providing the first detailed data on this cranial element in a Late Triassic ichthyosaurian. Furthermore, the specimen also demonstrates a distinctive condition of rib articulation in the anteriormost presacral (cervical) vertebrae, which together with other features allows for the erection of a new taxon – Auroroborealia incognita gen. et sp. nov. Although the phylogenetic position of this taxon is uncertain due to its fragmentary nature, its anatomy, indicating toretocnemid or parvipelvian affinities, further supports the previously hypothesised sister-group relationships between these two clades. The morphology of the parabasisphenoid and vertebral column of the new taxon is discussed in broader contexts of the patterns of evolution of these skeletal regions in ichthyosaurs.


2019 ◽  
Vol 188 (4) ◽  
pp. 976-1151 ◽  
Author(s):  
Jimmy Cabra-García ◽  
Gustavo Hormiga

Abstract We present a total evidence phylogenetic analysis of the Neotropical orb-weaving spider genus Wagneriana and discuss the phylogenetic impacts of methodological choices. We analysed 167 phenotypic characters and nine loci scored for 115 Wagneriana and outgroups, including 46 newly sequenced species. We compared total evidence analyses and molecular-only analyses to evaluate the impact of phenotypic evidence, and we performed analyses using the programs POY, TNT, RAxML, GARLI, IQ-TREE and MrBayes to evaluate the effects of multiple sequence alignment and optimality criteria. In all analyses, Wagneriana carimagua and Wagneriana uropygialis were nested in the genera Parawixia and Alpaida, respectively, and the remaining species of Wagneriana fell into three main clades, none of which formed a pair of sister taxa. However, sister-group relationships among the main clades and their internal relationships were strongly influenced by methodological choices. Alignment methods had comparable topological effects to those of optimality criteria in terms of ‘subtree pruning and regrafting’ moves. The inclusion of phenotypic evidence, 2.80–3.05% of the total evidence matrices, increased support irrespective of the optimality criterion used. The monophyly of some groups was recovered only after the addition of morphological characters. A new araneid genus, Popperaneus gen. nov., is erected, and Paraverrucosa is resurrected. Four new synonymies and seven new combinations are proposed.


Zootaxa ◽  
2008 ◽  
Vol 1817 (1) ◽  
pp. 49 ◽  
Author(s):  
VASILY V. GREBENNIKOV ◽  
ALFRED F. NEWTON

External morphology of larvae belonging to three unidentified genera of the rove-beetle subfamily Leptotyphlinae (Coleoptera: Staphylinidae) collected in Mexico, Chile and Australia, respectively, is described and illustrated. Larvae of Leptotyphlinae can be distinguished from all other Staphylinoidea larvae by the combination of their small size (maximum documented head width 0.128 mm), along with complete absence of eyes, lyriform frontal ecdysial lines, long coronal suture extending for about 40% of head length, short antennae not longer than 1/3 of head length, non-serrate mandibles with a single pre-apical tooth, tibiotarsi swollen in middle with two ventral spines, and indistinctly articulated short urogomphi not longer than twice their basal width. At least some of these characters are likely to support monophyly of the subfamily. Leptotyphlinae are hypothesized to belong to the Staphylinine Group of subfamilies sharing with at least some of them the following larval characters: labrum fully fused with clypeus; posterior tentorial arms extremely thin, thread-like and more than 20 times longer than wide; posterior tentorial pits short, rounded to elongate; cardo lacking transverse sclerotized ridge. The sister-group relationships of Leptotyphlinae to a clade of Pseudopsinae+Paederinae+Staphylininae is hypothesized with the following larval characters in support: lyriform frontal arms; each maxilla articulated laterally to head capsule by a condyle; maxillary mala parallel-sided (=finger-shaped) and articulated to stipes. A larval identification key to all three presently described genera is given.


Zootaxa ◽  
2018 ◽  
Vol 4415 (3) ◽  
pp. 452 ◽  
Author(s):  
P. R. PUGH ◽  
C.W. DUNN ◽  
S.H.D. HADDOCK

A new species of calycophoran siphonophore, Tottonophyes enigmatica gen. nov, sp. nov., is described. It has a unique combination of traits, some shared with prayomorphs (including two rounded nectophores) and some with clausophyid diphyomorphs (the nectophores are dissimilar, with one slightly larger and slightly to the anterior of the other, and both possess a somatocyst). Molecular phylogenetic analyses indicate that the new species is the sister group to all other diphyomorphs. A new family, Tottonophyidae, is established for it. Its phylogenetic position and distinct morphology help clarify diphyomorph evolution. The function and homology of the nectophoral canals and somatocyst is also re-examined and further clarification is given to their nomenclature.


2011 ◽  
Vol 80 (3) ◽  
pp. 169-178 ◽  
Author(s):  
Masato Owada ◽  
Bert W. Hoeksema

Research on the evolution of the symbiosis between the boring mussel Fungiacava eilatensis (Bivalvia: Mytilidae) and its mushroom coral hosts (Scleractinia: Fungiidae), which requires phylogenetic reconstructions of both the Mytilidae and the Fungiidae, contributes to the understanding of the complexity of coral reef ecosystems. Previously, Fungiacava was regarded as a genus that had descended from Leiosolenus or as belonging to the subfamily Crenellinae, but no phylogenetic support has been obtained for this hypothesis. In the present study, the 18s rRNA sequences of ten mytilid species and the shell microstructures of 12 mytilids were investigated. The phylogenetic position of F. eilatensis is discussed in relation to its associations with its host species. The results of the molecular phylogenetic analysis indicate that F. eilatensis forms a sister group with Leiosolenus simplex, a livecoral- boring species within the Leiosolenus clade. Scanning electron microscope observations indicate that the shell of F. eilatensis is constructed of 3 layers: the outer shell layer with a homogeneous structure, the middle shell layer as a sheet nacreous structure, and the inner shell layer with an irregular simple prism structure. This shell microstructure of F. eilatensis is similar to that of Leiosolenus malaccanus and L. simplex. These findings show that F. eilatensis has descended from a coral-boring Leiosolenus species and that it would be adequate for Fungiacava to be treated as Leiosolenus. However, because of its extraordinary shell shape it has been kept as a separate genus.


Zootaxa ◽  
2008 ◽  
Vol 1863 (1) ◽  
pp. 1 ◽  
Author(s):  
PATRICK S. DRUCKENMILLER ◽  
ANTHONY P. RUSSELL

Leptocleidus Andrews, 1922 is a poorly known plesiosaur genus from Lower Cretaceous successions of the UK, South Africa, and Australia. Historically, there has been little consensus regarding its phylogenetic position within Plesiosauria, largely because of its seemingly aberrant combination of a relatively small skull and short neck. As a result, a diverse array of potential sister groups have been posited for Leptocleidus, including long-necked Cretaceous elasmosaurids, Early Jurassic “rhomaleosaurs”, and Middle to Late Jurassic pliosaurids. A cladistic analysis including Leptocleidus, and a new, apparently morphologically similar specimen from Alberta, TMP 94.122.01, was undertaken to assess their phylogenetic position within Plesiosauria. A character-taxon matrix was assembled afresh, consisting of 33 operational taxonomic units sampled broadly among plesiosaurs. 185 cranial and postcranial characters used in plesiosaur phylogenetics were critically reanalyzed, of which 152 were employed in the parsimony analysis. The results indicate a basal dichotomous split into the traditionally recognized pliosauroid and plesiosauroid clades. Nested within Pliosauroidea, a monophyletic Leptocleididae was recovered, consisting of L. superstes Andrews, 1922 and L. capensis (Andrews, 1911a). In contrast to earlier suggestions, Leptocleidus neither clusters with Rhomaleosaurus, which was found to be paraphyletic, nor with large-skulled pliosaurid taxa, such as Simolestes. Rather, a sister group relationship between Cretaceous Polycotylidae and Leptocleididae was recovered, which is here named Leptocleidoidea. Although TMP 94.122.01 is superficially similar to Leptocleidus, several discrete characters of the skull nest this new taxon within Polycotylidae. Compared to other phylogenetic hypotheses of plesiosaurs, these results are more congruent with respect to the stratigraphic distribution of leptocleidoids. A classification for Plesiosauria is presented.


2021 ◽  
Author(s):  
Anna A. Namyatova ◽  
Michael D. Schwartz ◽  
Gerasimos Cassis

The Lygus-complex is one of the most taxonomically challenging groups of Miridae (Heteroptera), and its Australian fauna is poorly studied. Here we examine the Australian taxa of the Lygus-complex using morphological and molecular methods. After a detailed morphological study of the material collected throughout Australia, Taylorilygus nebulosus is transferred to Diomocoris, with the genus recorded for the first time in this country. Taylorilygus apicalis, also widely distributed in Australia, is redescribed on the basis of Australian material. The genus Micromimetus is recorded for the first time in Australia, with M. celiae, sp. nov., M. hannahae, sp. nov., M. nikolai, sp. nov. and M. shofneri, sp. nov. described as new to science. Micromimetus pictipes is redescribed and its distributional range is increased. The monophyly of the Lygus-complex and relationships within this group were tested using cytochrome c oxidase subunit I (COI), 16S rRNA, 18S rRNA and 28S rRNA markers. The Lygus-complex has been found to be non-monophyletic. Phylogeny confirmed the monophyly of Micromimetus, and it has shown that Taylorilygus apicalis is closer to Micromimetus species than to Diomocoris nebulosus. This study is the initial step in understanding the Lygus-complex phylogeny; analyses with more taxa, more genes and morphology are needed to reveal the interrelationships within this group, and sister-group relationships of Australian taxa. http://zoobank.org/urn:lsid:zoobank.org:pub:7393D96B-2BBA-438D-A134-D372EFE7FB9E


Zootaxa ◽  
2018 ◽  
Vol 4399 (2) ◽  
pp. 248 ◽  
Author(s):  
PEKKA VILKAMAA ◽  
HANS-GEORG RUDZINSKI ◽  
NIKOLA BURDÍKOVÁ ◽  
JAN ŠEVČÍK

Four Oriental species of Aerumnosa Mohrig, 1999 (Diptera: Sciaridae), a genus previously known only from Papua New Guinea, are newly described and illustrated: Aerumnosa bituberculata sp. n. (India), A. gemmifera sp. n. (Malaysia: Sabah), A. horrifica sp. n. (Brunei, Thailand) and A. impar sp. n. (Malaysia: Sabah). On the basis of the new material, the genus is redefined. A key to the known species of Aerumnosa is presented, including four new species. An updated molecular phylogenetic analysis based on four gene markers (18S, 28S, 16S and COI) shows Aerumnosa to be a member of the subfamily Cratyninae. The monophyly of Cratyninae is well supported, which clade also includes the genera Hyperlasion Schmitz, 1919, Pnyxiopalpus Vilkamaa & Hippa, 1999 and Pseudoaerumnosa Rudzinski, 2006. According to the present phylogenetic hypothesis, the monophyly of Cratyna Winnertz, 1967 s. l. needs to be revisited. The clade including Cratyna (s. str.) ambigua (Lengersdorf, 1934) appears as the sister group of Aerumnosa. 


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