Phylogenomic interrogation resolves the backbone of the Pseudoscorpiones tree of life.

Pseudoscorpiones, with nearly 3700 described species, are an ancient and globally distributed group of arachnids with a fossil record dating back to the Middle Devonian. Previous attempts to reconstruct their phylogenetic history have used morphology or a few amplicons, mostly of rRNAs and mitochondrial genes, which have not been able to completely resolve family-level relationships nor the earliest nodes in the pseudoscorpion tree-those which are most informative about the origins of key characters like venoms and silk. Here we undertake a phylogenetic approach using 41 pseudoscorpion transcriptomes and a series of analyses that account for many of the common pitfalls faced in large phylogenomic analyses. All analyses, using concatenation methods and coalescent approaches, supported monophyly of Iocheirata (the venomous pseudoscorpions), which diversified mostly during the Mesozoic, but paraphyly of Epiocheirata, with a sister group relationship of Feaelloidea to Iocheirata, with Chthonioidea as their sister group. These three main lineages were established during the mid-to-late Paleozoic. Our phylogenetic scheme is consistent with the prior hypothesis that the lack of venom in Pseudoscorpiones is plesiomorphic and not a synapomorphy of Epiocheirata. Based on the results of this study, a new classification is proposed for Pseudoscorpiones including the following new nomenclatural and taxonomic acts: the new suborders Palaeosphyronida Harvey and Atoposphyronida Harvey for Dracochelidae and Feaelloidea, respectively; the newly recognized superfamily Garypinoidea for Garypinidae and Larcidae; the revised rank for Lechytiidae and Tridenchthoniidae, which are regarded as subfamilies of Chthoniidae; the revised rank for Tridenchthoniini and Verrucadithini which are regarded as tribes of Tridenchthoniinae; and the elevation of Hesperolpiinae as a distinct family, Hesperolpiidae.

A revised dated phylogeny of scorpions: Phylogenomic support for ancient divergence of the temperate Gondwanan family Bothriuridae.

The scorpion family Bothriuridae occupies a subset of landmasses formerly constituting East and West temperate Gondwana, but its relationship to other scorpion families is in question. Whereas morphological data have strongly supported a sister group relationship of Bothriuridae and the superfamily Scorpionoidea, a recent phylogenomic analysis recovered a basal placement of bothriurids within Iurida, albeit sampling only a single exemplar. Here we reexamined the phylogenetic placement of the family Bothriuridae, sampling six bothriurid exemplars representing both East and West Gondwana, using transcriptomic data. Our results demonstrate that the sister group relationship of Bothriuridae to the clade ("Chactoidea" + Scorpionoidea) is supported by the inclusion of additional bothriurid taxa, and that this placement is insensitive to matrix completeness or partitioning by evolutionary rate. We also estimated divergence times within the order Scorpiones using multiple fossil calibrations, to infer whether the family Bothriuridae is sufficiently old to be characterized as a true Gondwanan lineage. We show that scorpions underwent ancient diversification between the Devonian and early Carboniferous. The age interval of the bothriurids sampled (a derived group that excludes exemplars from South Africa) spans the timing of breakup of temperate Gondwana.

Effect of castration on male rabbit lower urinary tract tissue enzymes.

OBJECTIVES: The influence of testosterone on the prostate and corpus cavernosum have been studied extensively. However, the influence of testosterone on the lower urinary tract (bladder and urethra) have not been investigated to any great extent. The aim of this study was to determine whether androgen deprivation alters lower urinary tract metabolism. METHODS: A total of 16 rabbits were divided into four groups of four rabbits each. Each rabbit in groups 1-3 underwent surgical bilateral castration for duration of 1, 2 , and 4 weeks, and group 4 underwent sham operations. Sections of bladder body and base wall and mucosa, urethra and corpora were isolated, frozen, and stored under liquid nitrogen. The activities of citrate synthase-thapsigargin sensitive Ca(2+) ATPase (Sarco/Endoplasmic Reticulum Ca(2+ )ATPase [SERCA]), and choline acetyl-transferase were examined as markers for mitochondrial function, sarcoplasmic reticular calcium storage and release, and cholinergic nerve function, respectively. RESULTS: The activity of SR function indicator, Ca(2+) ATPase was significantly higher in the control corpora than in the control bladder or urethra. Castration resulted in decreased activity in the mitochondria specific enzyme, citrate synthase, the activity of which was greatest in the urethra and lowest in the corpora. Cholinergic nerve density indicator, choline acetyl-transferase activity was greatest in the bladder body and lowest in the urethra. CONCLUSIONS: Our data indicate that (1) significant differences exist in the activities of all three enzymes in the various organs associated with the lower urinary tract; and (2) that castration results in significant alterations in the activities of all three enzymes in the bladder body, base, urethra, and corpora.