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1. Phylogenetic review of the millipede genus Cherokia Chamberlin, 1949 (Polydesmida, Xystodesmidae)

   https://doi.org/10.3897/zookeys.1106.81386  

   Vasquez-Valverde, Luisa Fernanda; Marek, Paul E. (June 2022, ZooKeys)

   The millipede genus Cherokia Chamberlin, 1949 is a monospecific taxon, with the type species Cherokia georgiana (Bollman, 1889). The last revision of the genus was made by Hoffman (1960) where he established three subspecies. Here we used molecular phylogenetics to assess the genus and evaluate whether it is a monophyletic group, and if the subspecies are each monophyletic. We included material from literature records and three natural history collections. Newly collected samples were obtained through a citizen science project. Morphological characters underlying subspecies groups—the shape of the paranota, body size, and coloration—were evaluated. A molecular phylogeny of the genus was estimated based on DNA sequences for seven gene loci, and a species delimitation analysis was used to evaluate the status of the subspecies. The documented geographical range of Cherokia in the United States was expanded to include a newly reported state record (Virginia) and about 160 new localities compared to the previously known range. Morphological characters, which included the shape of the paranota and body size that had been historically used to establish subspecies, showed clinal variation with a direct relationship with geographical distribution and elevation, but not with phylogeny. Coloration was highly variable and did not accord with geography or phylogeny. The phylogeny recovered Cherokia as a monophyletic lineage, and the species delimitation test supported the existence of a single species. The subspecies Cherokia georgiana ducilla (Chamberlin, 1939) and Cherokia georgiana latassa Hoffman, 1960 have been synonymized with Cherokia georgiana . The molecular and morphological evidence showed that Cherokia is a monospecific genus with the sole species, Cherokia georgiana , being geographically widespread and highly variable in its morphology. 

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2. Myxococcus xanthus fruiting body morphology is important for spore recovery after exposure to environmental stress

   https://doi.org/10.1128/aem.01660-24  

   Lall, Dave; Glaser, Maike M; Higgs, Penelope I (October 2024, Applied and Environmental Microbiology)

   Glass, Jennifer B (Ed.)

   ABSTRACT Environmental microorganisms have evolved a variety of strategies to survive fluctuations in environmental conditions, including the production of biofilms and differentiation into spores.Myxococcus xanthusare ubiquitous soil bacteria that produce starvation-induced multicellular fruiting bodies filled with environmentally resistant spores (a specialized biofilm). Isolated spores have been shown to be more resistant than vegetative cells to heat, ultraviolet radiation, and desiccation. The evolutionary advantage of producing spores inside fruiting bodies is not clear. Here, we examine a hypothesis that the fruiting body provides additional protection from environmental insults. We developed a high-throughput method to compare the recovery (outgrowth) of distinct cell types (vegetative cells, free spores, and spores within intact fruiting bodies) after exposure to ultraviolet radiation or desiccation. Our data indicate that haystack-shaped fruiting bodies protect spores from extended UV radiation but do not provide additional protection from desiccation. Perturbation of fruiting body morphology strongly impedes recovery from both UV exposure and desiccation. These results hint that the distinctive fruiting bodies produced by different myxobacterial species may have evolved to optimize their persistence in distinct ecological niches.IMPORTANCEEnvironmental microorganisms play an important role in the production of greenhouse gases that contribute to changing climate conditions. It is imperative to understand how changing climate conditions feedback to influence environmental microbial communities. The myxobacteria are environmentally ubiquitous social bacteria that influence the local microbial community composition. Defining how these bacteria are affected by environmental insults is a necessary component of predicting climatic feedback effects. When starved, myxobacteria produce multicellular fruiting bodies filled with spores. As spores are resistant to a variety of environmental insults, the evolutionary advantage of building a fruiting body is not clear. Using the model myxobacterium,Myxococcus xanthus, we demonstrate that the tall, haystack-shaped fruiting body morphology enables significantly more resistance to UV exposure than the free spores. In contrast, fruiting bodies are slightly detrimental to recovery from extended desiccation, an effect that is strongly exaggerated if fruiting body morphology is perturbed. These results suggest that the variety of fruiting body morphologies observed in the myxobacteria may dictate their relative resistance to changing climate conditions. 

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3. Integrating UCE Phylogenomics With Traditional Taxonomy Reveals a Trove of New World Syscia Species (Formicidae: Dorylinae)

   https://doi.org/10.1093/isd/ixab001  

   Longino, John T; Branstetter, Michael G (March 2021, Insect Systematics and Diversity)

   Hines, Heather (Ed.)

   Abstract The ant genus Syscia  Roger, 1861 is part of the cryptic ant fauna inhabiting leaf litter and rotten wood in the Asian and American tropics. It is a distinct clade within the Dorylinae, the subfamily from which army ants arose. Prior to this work, the genus comprised seven species, each known from a single or very few collections. Extensive collecting in Middle America revealed an unexpected and challenging diversity of morphological forms. Locally distinct forms could be identified at many sites, but assignment of specimens to species spanning multiple sites was problematic. To improve species delimitation, Ultra-Conserved Element (UCE) phylogenomic data were sequenced for all forms, both within and among sites, and a phylogeny was inferred. Informed by phylogeny, species delimitation was based on monophyly, absence of within-clade sympatry, and a subjective degree of morphological uniformity. UCE phylogenomic results for 130 specimens were complemented by analysis of mitochondrial COI (DNA barcode) data for an expanded taxon set. The resulting taxonomy augments the number of known species in the New World from 3 to 57. We describe and name 31 new species, and 23 species are assigned morphospecies codes pending improved specimen coverage. Queens may be fully alate or brachypterous, and there is a wide variety of intercaste female forms. Identification based on morphology alone is very difficult due to continuous character variation and high similarity of phylogenetically distant species. An identification aid is provided in the form of a set of distribution maps and standard views, with species ordered by size. 

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4. Are Palmer’s Elm-Leaf Goldenrod and the Smooth Elm-Leaf Goldenrod Real? The Angiosperms353 Kit Provides Within-Species Signal in Solidago ulmifolia s. l.

   https://doi.org/10.1600/036364421X16370109698740  

   Beck, James B.; Markley, Morgan L.; Zielke, Mackenzie G.; Thomas, Justin R.; Hale, Haley J.; Williams, Lindsay D.; Johnson, Matthew G. (December 2021, Systematic Botany)

   Abstract— The genus Solidago represents a taxonomically challenging group due to its sheer number of species, putative hybridization, polyploidy, and shallow genetic divergence among species. Here we use a dataset obtained exclusively from herbarium specimens to evaluate the status of Solidago ulmifolia var. palmeri , a morphologically subtle taxon potentially confined to Alabama, Arkansas, Mississippi, and Missouri. A multivariate analysis of both discrete and continuous morphological data revealed no clear distinction between S. ulmifolia var. palmeri and Solidago ulmifolia var. ulmifolia . Solidago ulmifolia var. palmeri ’s status was also assessed with a phylogenomic and SNP clustering analysis of data generated with the “Angiosperms353” probe kit. Neither analysis supported Solidago ulmifolia var. palmeri as a distinct taxon, and we suggest that this name should be discarded. The status of Solidago delicatula (formerly known as Solidago ulmifolia var. microphylla ) was also assessed. Both morphological and phylogenetic analyses supported the species status of S. delicatula and we suggest maintaining this species at its current rank. These results highlight the utility of the Angiosperms353 probe kit, both with herbarium tissue and at lower taxonomic levels. Indeed, this is the first study to utilize this kit to identify genetic groups within a species. 

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5. A new species of thick-toed gecko (Pachydactylus) from Serra da Neve and surrounding rocky areas of southwestern Angola

   Marques, M.P.; Parrinha, D.; Ceriaco, L.M.P.; Brennan, I.G.; Heinicke, M.P.; Bauer, A.M. (April 2023, Vertebrate zoology)

   Several specimens of Pachydactylus angolensis, a poorly known Angolan endemic gecko, have recently been collected in southern Angola, considerably increasing its known distribution range. Previous observations led to the hypothesis that two different morphological forms exist in the country — a coastal form and an inland form. Based on the morphological examination of historical and recently collected specimens, as well as on newly generated molecular data, we conducted a taxonomic revision of this putative species complex. The results support the separation of these two forms as two different species. The coastal form belongs to the nominotypic population, while the inland form is here described as a new species, Pachydactylus maiatoi sp. nov. A brief comment on the biogeographical implications of this discovery is also provided. 

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