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1. The early actinopterygian genus Rhadinichthys redefined, the type species ornatissimus redescribed, and the species bearsdeni introduced

   https://doi.org/10.1017/S1755691024000136  

   MO, Yunyan; CARON, Abigail M; COATES, Michael I (October 2024, Earth and Environmental Science Transactions of the Royal Society of Edinburgh)

   ABSTRACT Rhadinichthysis one of the most wide-ranging and speciose genera of Palaeozoic actinopterygians. A classic variety of ‘palaeoniscoid’,Rhadinichthysspecies are generally small (~10–15 cm) and known mostly from dermal skeletal remains that show features commonplace among early ray-finned fishes. For this reason, the genus has long been considered a poorly diagnosed wastebasket taxon in need of revision and rarely included in systematic analyses. In the present work, syntypes ofRhadinichthys ornatissimus, the type species, are re-examined and supplemented with better-preserved material from other localities in the Scottish Midland Valley. A neotype is nominated and a more precise diagnosis presented with a suite of genus-level apomorphies. Unexpectedly, these traits are also evident in the monotypic Lower Carboniferous actinopterygian genusWoodichthys, which the neotype ofR. ornatissimusclosely resembles. As a result, the genusWoodichthysis subsumed within the redefinedRhadinichthys, and the singleWoodichthysspecies is reassigned asR. bearsdeni, comb. nov., bringing with it a set of endoskeletal data. Some of these data are new, derived from μCT scans of the skull of theR. bearsdeniholotype, yielding renderings that update the original description of its skull table, parasphenoid, neurocranium, and otoliths. Further new data concerning the hyoid arch are obtained from a new specimen ofR. bearsdenifrom a site close by the original Bearsden locality. Redefined in this way,Rhadinichthyspresents a data-rich operational taxonomic unit better suited for systematic studies. However, in so doing, it also releases a cluster of fossil species no longer anchored to a genus and now in need of rediagnoses. 

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2. Deep time extinction of largest insular ant predators and the first fossil Neoponera (Formicidae: Ponerinae) from Miocene age Dominican amber

   https://doi.org/10.1186/s12915-022-01488-9  

   Fiorentino, Gianpiero; Lattke, John; Troya, Adrian; Sosiak, Christine; Dong, Minsoo; Barden, Phillip (February 2023, BMC Biology)

   Abstract BackgroundPonerine ants are almost exclusively predatory and comprise many of the largest known ant species. Within this clade, the genusNeoponerais among the most conspicuous Neotropical predators. We describe the first fossil member of this lineage: a worker preserved in Miocene-age Dominican amber from Hispaniola. ResultsNeoponera vejestoriasp. nov. demonstrates a clear case of local extinction—there are no known extantNeoponeraspecies in the Greater Antilles. The species is attributable to an extant and well-defined species group in the genus, which suggests the group is older than previously estimated. Through CT scan reconstruction and linear morphometrics, we reconstruct the morphospace of extant and fossil ants to evaluate the history and evolution of predatory taxa in this island system. ConclusionsThe fossil attests to a shift in insular ecological community structure since the Miocene. The largest predatory taxa have undergone extinction on the island, but their extant relatives persist throughout the Neotropics.Neoponera vejestoriasp. nov. is larger than all other predatory ant workers known from Hispaniola, extant or extinct. Our results empirically demonstrate the loss of a functional niche associated with body size, which is a trait long hypothesized to be related to extinction risk. 

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3. Paludicola gen. nov. and Revision of the Species Formerly in Batrachospermum Section  Turfosa (Batrachospermales, Rhodophyta)

   https://doi.org/10.1111/jpy.13001  

   Vis, Morgan L.; Lee, Janina; Eloranta, Pertti; Chapuis, Iara S.; Lam, Daryl W.; Necchi, Jr., Orlando; Oliveira, ed., M. C. (May 2020, Journal of Phycology)

   Since the first phylogenetic study of the order Batrachospermales,Batrachospermumwas shown to be paraphyletic. Subsequently, sections of the genus have been methodically investigated usingDNAsequences and morphology in order to propose new genera and delineate species.BatrachospermumsectionTurfosais the last section with multiple species yet to be examined. New sequence data of specimens from Europe and the United States were combined with the sparse sequence data already available. Phylogenetic analyses usingrbcL andCOI‐5P sequences showed this section to be a well‐supported clade, distinct fromBatrachospermumsectionBatrachospermumand its segregate genera. Section Turfosais raised to the generic rank asPaludicolagen. nov. Substantial genetic variation within the genus was discovered and 12 species are recognized based onDNAsequence data as well as morphological characters and geographic distribution. The following morphological characters were applied to distinguish species: branching pattern (pseudodichotomous or irregular), whorl size (reduced or well developed), primary fascicles (curved or straight), spermatangia origin (primary or secondary fascicles), and carposporophyte arrangement (loose or dense). Previously published species were transferred to the new genus:P. turfosa,P. keratophyta,P. orthosticha,P. phangiae,andP. periploca. Seven new species are proposed as follows:P. groenbladiifrom Europe;P. communis,P. johnhallii, andP. leafensisfrom North America; andP. aquanigra,P. diamantinensis, andP. turfosiformisfrom Brazil. In addition, three unsequenced species in the section,P. bakarensis,P. gombakensis, andP. tapirensis, were transferred to the new genus. 

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4. Molecular phylogeny of Spirotrichonymphea (Parabasalia) with emphasis on Spironympha , Spirotrichonympha , and three new genera Pseudospironympha , Nanospironympha , and Brugerollina

   https://doi.org/10.1111/jeu.12967  

   Noda, Satoko; Kitade, Osamu; Jasso‐Selles, Daniel E.; Taerum, Stephen J.; Takayanagi, Miki; Radek, Renate; Lo, Nathan; Ohkuma, Moriya; Gile, Gillian H. (February 2023, Journal of Eukaryotic Microbiology)

   Abstract Spirotrichonymphea, one of the six classes of phylum Parabasalia, are characterized by bearing many flagella in spiral rows, and they occur exclusively in the guts of termites. Phylogenetic relationships among the 13 described genera are not well understood due to complex morphological evolution and a paucity of molecular data. One such understudied genus isSpironympha. It has been variously considered a valid genus, a subgenus ofSpirotrichonympha, or an “immature” life cycle stage ofSpirotrichonympha. To clarify this, we sequenced the small subunit rRNA gene sequences ofSpironymphaandSpirotrichonymphacells isolated from the hindguts ofReticulitermesspecies andHodotermopsis sjostedtiand confirmed the molecular identity ofH. sjostedtisymbionts using fluorescence in situ hybridization.Spironymphaas currently circumscribed is polyphyletic, with bothH. sjostedtisymbiont species branching separately from the “true”SpironymphafromReticulitermes. Similarly, theSpirotrichonymphasymbiont ofH. sjostedtibranches separately from the “true”Spirotrichonymphafound inReticulitermes. Our data supportSpironymphafromReticulitermesas a valid genus most closely related toSpirotrichonympha, though its monophyly and interspecific relationships are not resolved in our molecular phylogenetic analysis. We propose three new genera to accommodate theH. sjostedtisymbionts and two new species ofSpirotrichonymphafromReticulitermes. 

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5. Phylogenetics and host‐specificity of the mega‐diverse louse genus Myrsidea (Amblycera: Menoponidae)

   https://doi.org/10.1111/syen.12536  

   Kolencik, Stanislav; Cacioppo, Joseph_A; Johnson, Kevin_P; Allen, Julie_M; Sychra, Oldrich; Weckstein, Jason_D (January 2022, Systematic Entomology)

   Abstract MyrsideaWaterston is the most diverse genus of chewing lice, primarily parasitizing perching birds (Passeriformes), which is the most speciose avian order.Myrsideaalso parasitize several hosts from non‐passerine groups, including toucans, barbets, woodpeckers (Piciformes) and hummingbirds (Apodiformes). To examine host specificity, host switching and generic limits, we reconstructed a phylogeny of the avian feather louse genusMyrsideausing DNA sequence data from two fragments of the mitochondrial COI gene and a fragment of the nuclear EF‐1α gene for 152Myrsideaspecimens collected from 23 avian host families. Unlike other highly diverse louse genera, only a small proportion ofMyrsideaspecies parasitize more than one host species. We found that host family has significant phylogenetic signal on theMyrsideaphylogeny. These results suggest thatMyrsideais generally highly host‐specific, with some exceptions where host switching is important. We found that there are two separate groups ofMyrsideathat parasitize toucans, and that both are nested withinMyrsideafound on perching birds, suggesting that these toucan ectoparasites may have arisen from two independent host switching events. Lastly, representatives of the genusRamphasticolaCarriker, which was originally described as a distinct genus due to a suite of morphologically unique characters, falls in with a strongly supported clade ofMyrsideaparasitizingRamphastostoucans, and therefore we definitively placeRamphasticolaas a synonym ofMyrsidea. 

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